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Annotation of src/usr.bin/make/make.1, Revision 1.238

1.238   ! dholland    1: .\"    $NetBSD: make.1,v 1.237 2014/09/09 06:39:59 dholland Exp $
1.15      thorpej     2: .\"
1.16      christos    3: .\" Copyright (c) 1990, 1993
                      4: .\"    The Regents of the University of California.  All rights reserved.
1.1       cgd         5: .\"
                      6: .\" Redistribution and use in source and binary forms, with or without
                      7: .\" modification, are permitted provided that the following conditions
                      8: .\" are met:
                      9: .\" 1. Redistributions of source code must retain the above copyright
                     10: .\"    notice, this list of conditions and the following disclaimer.
                     11: .\" 2. Redistributions in binary form must reproduce the above copyright
                     12: .\"    notice, this list of conditions and the following disclaimer in the
                     13: .\"    documentation and/or other materials provided with the distribution.
1.84      agc        14: .\" 3. Neither the name of the University nor the names of its contributors
1.1       cgd        15: .\"    may be used to endorse or promote products derived from this software
                     16: .\"    without specific prior written permission.
                     17: .\"
                     18: .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
                     19: .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
                     20: .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
                     21: .\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
                     22: .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
                     23: .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
                     24: .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
                     25: .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
                     26: .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
                     27: .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
                     28: .\" SUCH DAMAGE.
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1.16      christos   30: .\"    from: @(#)make.1        8.4 (Berkeley) 3/19/94
1.1       cgd        31: .\"
1.238   ! dholland   32: .Dd September 9, 2014
1.1       cgd        33: .Dt MAKE 1
                     34: .Os
                     35: .Sh NAME
                     36: .Nm make
                     37: .Nd maintain program dependencies
                     38: .Sh SYNOPSIS
1.74      wiz        39: .Nm
1.219     christos   40: .Op Fl BeikNnqrstWwX
1.159     sjg        41: .Op Fl C Ar directory
1.1       cgd        42: .Op Fl D Ar variable
                     43: .Op Fl d Ar flags
                     44: .Op Fl f Ar makefile
                     45: .Op Fl I Ar directory
1.104     wiz        46: .Op Fl J Ar private
                     47: .Op Fl j Ar max_jobs
1.13      christos   48: .Op Fl m Ar directory
1.44      sommerfe   49: .Op Fl T Ar file
1.16      christos   50: .Op Fl V Ar variable
1.1       cgd        51: .Op Ar variable=value
                     52: .Op Ar target ...
                     53: .Sh DESCRIPTION
1.25      lukem      54: .Nm
1.1       cgd        55: is a program designed to simplify the maintenance of other programs.
                     56: Its input is a list of specifications as to the files upon which programs
                     57: and other files depend.
1.128     dsl        58: If no
                     59: .Fl f Ar makefile
                     60: makefile option is given,
                     61: .Nm
                     62: will try to open
1.1       cgd        63: .Ql Pa makefile
1.128     dsl        64: then
1.1       cgd        65: .Ql Pa Makefile
1.128     dsl        66: in order to find the specifications.
1.1       cgd        67: If the file
                     68: .Ql Pa .depend
                     69: exists, it is read (see
1.66      wiz        70: .Xr mkdep 1 ) .
1.1       cgd        71: .Pp
                     72: This manual page is intended as a reference document only.
                     73: For a more thorough description of
1.25      lukem      74: .Nm
1.1       cgd        75: and makefiles, please refer to
1.197     dholland   76: .%T "PMake \- A Tutorial" .
1.1       cgd        77: .Pp
1.128     dsl        78: .Nm
                     79: will prepend the contents of the
                     80: .Va MAKEFLAGS
                     81: environment variable to the command line arguments before parsing them.
                     82: .Pp
1.1       cgd        83: The options are as follows:
                     84: .Bl -tag -width Ds
1.16      christos   85: .It Fl B
1.10      christos   86: Try to be backwards compatible by executing a single shell per command and
                     87: by executing the commands to make the sources of a dependency line in sequence.
1.159     sjg        88: .It Fl C Ar directory
                     89: Change to
                     90: .Ar directory
                     91: before reading the makefiles or doing anything else.
                     92: If multiple
                     93: .Fl C
                     94: options are specified, each is interpreted relative to the previous one:
                     95: .Fl C Pa / Fl C Pa etc
                     96: is equivalent to
                     97: .Fl C Pa /etc .
1.1       cgd        98: .It Fl D Ar variable
1.8       christos   99: Define
                    100: .Ar variable
1.1       cgd       101: to be 1, in the global context.
1.128     dsl       102: .It Fl d Ar [-]flags
1.1       cgd       103: Turn on debugging, and specify which portions of
1.25      lukem     104: .Nm
1.1       cgd       105: are to print debugging information.
1.128     dsl       106: Unless the flags are preceded by
1.194     sjg       107: .Ql \-
1.128     dsl       108: they are added to the
                    109: .Va MAKEFLAGS
                    110: environment variable and will be processed by any child make processes.
1.141     apb       111: By default, debugging information is printed to standard error,
1.138     apb       112: but this can be changed using the
1.140     wiz       113: .Ar F
1.138     apb       114: debugging flag.
1.139     apb       115: The debugging output is always unbuffered; in addition, if debugging
                    116: is enabled but debugging output is not directed to standard output,
                    117: then the standard output is line buffered.
1.1       cgd       118: .Ar Flags
                    119: is one or more of the following:
                    120: .Bl -tag -width Ds
                    121: .It Ar A
                    122: Print all possible debugging information;
                    123: equivalent to specifying all of the debugging flags.
                    124: .It Ar a
                    125: Print debugging information about archive searching and caching.
1.147     christos  126: .It Ar C
                    127: Print debugging information about current working directory.
1.1       cgd       128: .It Ar c
                    129: Print debugging information about conditional evaluation.
                    130: .It Ar d
                    131: Print debugging information about directory searching and caching.
1.88      jmmv      132: .It Ar e
                    133: Print debugging information about failed commands and targets.
1.138     apb       134: .It Ar F Ns Oo Sy \&+ Oc Ns Ar filename
                    135: Specify where debugging output is written.
                    136: This must be the last flag, because it consumes the remainder of
                    137: the argument.
                    138: If the character immediately after the
                    139: .Ql F
                    140: flag is
                    141: .Ql \&+ ,
                    142: then the file will be opened in append mode;
                    143: otherwise the file will be overwritten.
                    144: If the file name is
                    145: .Ql stdout
                    146: or
                    147: .Ql stderr
                    148: then debugging output will be written to the
                    149: standard output or standard error output file descriptors respectively
                    150: (and the
                    151: .Ql \&+
                    152: option has no effect).
                    153: Otherwise, the output will be written to the named file.
                    154: If the file name ends
1.128     dsl       155: .Ql .%d
                    156: then the
                    157: .Ql %d
                    158: is replaced by the pid.
1.87      jmmv      159: .It Ar f
                    160: Print debugging information about loop evaluation.
1.1       cgd       161: .It Ar "g1"
                    162: Print the input graph before making anything.
                    163: .It Ar "g2"
                    164: Print the input graph after making everything, or before exiting
1.93      dsl       165: on error.
1.92      dsl       166: .It Ar "g3"
                    167: Print the input graph before exiting on error.
1.1       cgd       168: .It Ar j
                    169: Print debugging information about running multiple shells.
1.135     sjg       170: .It Ar l
                    171: Print commands in Makefiles regardless of whether or not they are prefixed by
1.137     wiz       172: .Ql @
1.135     sjg       173: or other "quiet" flags.
                    174: Also known as "loud" behavior.
1.180     sjg       175: .It Ar M
                    176: Print debugging information about "meta" mode decisions about targets.
1.1       cgd       177: .It Ar m
                    178: Print debugging information about making targets, including modification
                    179: dates.
1.111     jmc       180: .It Ar n
1.154     apb       181: Don't delete the temporary command scripts created when running commands.
                    182: These temporary scripts are created in the directory
                    183: referred to by the
                    184: .Ev TMPDIR
                    185: environment variable, or in
1.112     wiz       186: .Pa /tmp
1.154     apb       187: if
                    188: .Ev TMPDIR
                    189: is unset or set to the empty string.
                    190: The temporary scripts are created by
                    191: .Xr mkstemp 3 ,
1.112     wiz       192: and have names of the form
1.154     apb       193: .Pa makeXXXXXX .
1.123     wiz       194: .Em NOTE :
1.156     snj       195: This can create many files in
1.154     apb       196: .Ev TMPDIR
                    197: or
                    198: .Pa /tmp ,
1.123     wiz       199: so use with care.
1.119     dsl       200: .It Ar p
                    201: Print debugging information about makefile parsing.
1.1       cgd       202: .It Ar s
                    203: Print debugging information about suffix-transformation rules.
                    204: .It Ar t
                    205: Print debugging information about target list maintenance.
1.205     sjg       206: .It Ar V
                    207: Force the
                    208: .Fl V
1.206     wiz       209: option to print raw values of variables.
1.1       cgd       210: .It Ar v
                    211: Print debugging information about variable assignment.
1.49      sjg       212: .It Ar x
1.57      wiz       213: Run shell commands with
                    214: .Fl x
                    215: so the actual commands are printed as they are executed.
1.1       cgd       216: .El
                    217: .It Fl e
1.68      perry     218: Specify that environment variables override macro assignments within
1.1       cgd       219: makefiles.
                    220: .It Fl f Ar makefile
                    221: Specify a makefile to read instead of the default
1.103     wiz       222: .Ql Pa makefile .
1.1       cgd       223: If
                    224: .Ar makefile
                    225: is
                    226: .Ql Fl ,
                    227: standard input is read.
1.103     wiz       228: Multiple makefiles may be specified, and are read in the order specified.
1.1       cgd       229: .It Fl I Ar directory
                    230: Specify a directory in which to search for makefiles and included makefiles.
1.13      christos  231: The system makefile directory (or directories, see the
                    232: .Fl m
                    233: option) is automatically included as part of this list.
1.1       cgd       234: .It Fl i
                    235: Ignore non-zero exit of shell commands in the makefile.
                    236: Equivalent to specifying
                    237: .Ql Fl
                    238: before each command line in the makefile.
1.44      sommerfe  239: .It Fl J Ar private
                    240: This option should
                    241: .Em not
                    242: be specified by the user.
                    243: .Pp
                    244: When the
                    245: .Ar j
                    246: option is in use in a recursive build, this option is passed by a make
                    247: to child makes to allow all the make processes in the build to
                    248: cooperate to avoid overloading the system.
1.1       cgd       249: .It Fl j Ar max_jobs
                    250: Specify the maximum number of jobs that
1.25      lukem     251: .Nm
1.67      grant     252: may have running at any one time.
1.180     sjg       253: The value is saved in
                    254: .Va .MAKE.JOBS .
1.67      grant     255: Turns compatibility mode off, unless the
1.11      christos  256: .Ar B
                    257: flag is also specified.
1.148     christos  258: When compatibility mode is off, all commands associated with a
                    259: target are executed in a single shell invocation as opposed to the
                    260: traditional one shell invocation per line.
                    261: This can break traditional scripts which change directories on each
                    262: command invocation and then expect to start with a fresh environment
                    263: on the next line.
                    264: It is more efficient to correct the scripts rather than turn backwards
                    265: compatibility on.
1.1       cgd       266: .It Fl k
                    267: Continue processing after errors are encountered, but only on those targets
                    268: that do not depend on the target whose creation caused the error.
1.13      christos  269: .It Fl m Ar directory
                    270: Specify a directory in which to search for sys.mk and makefiles included
1.99      wiz       271: via the
                    272: .Ao Ar file Ac Ns -style
                    273: include statement.
1.98      chuck     274: The
                    275: .Fl m
                    276: option can be used multiple times to form a search path.
1.13      christos  277: This path will override the default system include path: /usr/share/mk.
                    278: Furthermore the system include path will be appended to the search path used
1.99      wiz       279: for
                    280: .Qo Ar file Qc Ns -style
                    281: include statements (see the
1.13      christos  282: .Fl I
                    283: option).
1.98      chuck     284: .Pp
                    285: If a file or directory name in the
                    286: .Fl m
1.99      wiz       287: argument (or the
                    288: .Ev MAKESYSPATH
                    289: environment variable) starts with the string
                    290: .Qq \&.../
                    291: then
                    292: .Nm
                    293: will search for the specified file or directory named in the remaining part
                    294: of the argument string.
                    295: The search starts with the current directory of
1.98      chuck     296: the Makefile and then works upward towards the root of the filesystem.
1.99      wiz       297: If the search is successful, then the resulting directory replaces the
                    298: .Qq \&.../
                    299: specification in the
1.98      chuck     300: .Fl m
1.99      wiz       301: argument.
                    302: If used, this feature allows
1.98      chuck     303: .Nm
                    304: to easily search in the current source tree for customized sys.mk files
1.99      wiz       305: (e.g., by using
                    306: .Qq \&.../mk/sys.mk
                    307: as an argument).
1.1       cgd       308: .It Fl n
1.45      sommerfe  309: Display the commands that would have been executed, but do not
                    310: actually execute them unless the target depends on the .MAKE special
1.64      wiz       311: source (see below).
1.45      sommerfe  312: .It Fl N
                    313: Display the commands which would have been executed, but do not
                    314: actually execute any of them; useful for debugging top-level makefiles
                    315: without descending into subdirectories.
1.1       cgd       316: .It Fl q
                    317: Do not execute any commands, but exit 0 if the specified targets are
                    318: up-to-date and 1, otherwise.
                    319: .It Fl r
                    320: Do not use the built-in rules specified in the system makefile.
                    321: .It Fl s
                    322: Do not echo any commands as they are executed.
                    323: Equivalent to specifying
                    324: .Ql Ic @
                    325: before each command line in the makefile.
1.44      sommerfe  326: .It Fl T Ar tracefile
                    327: When used with the
1.48      wiz       328: .Fl j
1.44      sommerfe  329: flag,
                    330: append a trace record to
                    331: .Ar tracefile
                    332: for each job started and completed.
1.1       cgd       333: .It Fl t
                    334: Rather than re-building a target as specified in the makefile, create it
                    335: or update its modification time to make it appear up-to-date.
1.16      christos  336: .It Fl V Ar variable
                    337: Print
1.74      wiz       338: .Nm Ns 's
1.16      christos  339: idea of the value of
                    340: .Ar variable ,
                    341: in the global context.
                    342: Do not build any targets.
                    343: Multiple instances of this option may be specified;
                    344: the variables will be printed one per line,
                    345: with a blank line for each null or undefined variable.
1.85      sjg       346: If
                    347: .Ar variable
                    348: contains a
                    349: .Ql \&$
                    350: then the value will be expanded before printing.
1.46      christos  351: .It Fl W
                    352: Treat any warnings during makefile parsing as errors.
1.238   ! dholland  353: .It Fl w
        !           354: Print entering and leaving directory messages, pre and post processing.
1.75      thorpej   355: .It Fl X
                    356: Don't export variables passed on the command line to the environment
                    357: individually.
                    358: Variables passed on the command line are still exported
                    359: via the
                    360: .Va MAKEFLAGS
                    361: environment variable.
                    362: This option may be useful on systems which have a small limit on the
                    363: size of command arguments.
1.1       cgd       364: .It Ar variable=value
                    365: Set the value of the variable
                    366: .Ar variable
                    367: to
                    368: .Ar value .
1.75      thorpej   369: Normally, all values passed on the command line are also exported to
                    370: sub-makes in the environment.
                    371: The
                    372: .Fl X
                    373: flag disables this behavior.
1.101     wiz       374: Variable assignments should follow options for POSIX compatibility
1.100     ross      375: but no ordering is enforced.
1.1       cgd       376: .El
                    377: .Pp
1.6       cgd       378: There are seven different types of lines in a makefile: file dependency
1.1       cgd       379: specifications, shell commands, variable assignments, include statements,
1.6       cgd       380: conditional directives, for loops, and comments.
1.1       cgd       381: .Pp
                    382: In general, lines may be continued from one line to the next by ending
                    383: them with a backslash
                    384: .Pq Ql \e .
1.237     dholland  385: The trailing newline character and initial whitespace on the following
                    386: line are compressed into a single space.
1.1       cgd       387: .Sh FILE DEPENDENCY SPECIFICATIONS
1.237     dholland  388: Dependency lines consist of one or more targets, an operator, and zero
                    389: or more sources.
1.137     wiz       390: This creates a relationship where the targets
                    391: .Dq depend
                    392: on the sources
1.1       cgd       393: and are usually created from them.
                    394: The exact relationship between the target and the source is determined
1.237     dholland  395: by the operator that separates them.
1.1       cgd       396: The three operators are as follows:
                    397: .Bl -tag -width flag
                    398: .It Ic \&:
                    399: A target is considered out-of-date if its modification time is less than
                    400: those of any of its sources.
                    401: Sources for a target accumulate over dependency lines when this operator
                    402: is used.
                    403: The target is removed if
1.25      lukem     404: .Nm
1.1       cgd       405: is interrupted.
                    406: .It Ic \&!
                    407: Targets are always re-created, but not until all sources have been
                    408: examined and re-created as necessary.
                    409: Sources for a target accumulate over dependency lines when this operator
                    410: is used.
                    411: The target is removed if
1.25      lukem     412: .Nm
1.1       cgd       413: is interrupted.
                    414: .It Ic \&::
                    415: If no sources are specified, the target is always re-created.
                    416: Otherwise, a target is considered out-of-date if any of its sources has
                    417: been modified more recently than the target.
                    418: Sources for a target do not accumulate over dependency lines when this
1.237     dholland  419: operator is used.
1.1       cgd       420: The target will not be removed if
1.25      lukem     421: .Nm
1.1       cgd       422: is interrupted.
                    423: .El
                    424: .Pp
                    425: Targets and sources may contain the shell wildcard values
1.80      wiz       426: .Ql \&? ,
1.1       cgd       427: .Ql * ,
1.103     wiz       428: .Ql [] ,
1.1       cgd       429: and
                    430: .Ql {} .
                    431: The values
1.80      wiz       432: .Ql \&? ,
1.103     wiz       433: .Ql * ,
1.1       cgd       434: and
                    435: .Ql []
                    436: may only be used as part of the final
                    437: component of the target or source, and must be used to describe existing
                    438: files.
                    439: The value
                    440: .Ql {}
                    441: need not necessarily be used to describe existing files.
                    442: Expansion is in directory order, not alphabetically as done in the shell.
                    443: .Sh SHELL COMMANDS
1.237     dholland  444: Each target may have associated with it a series of shell commands, normally
                    445: used to create the target.
                    446: Each of the commands in this script
1.1       cgd       447: .Em must
                    448: be preceded by a tab.
1.237     dholland  449: While any target may appear on a dependency line, only one of these
                    450: dependencies may be followed by a creation script, unless the
1.91      lukem     451: .Ql Ic \&::
1.1       cgd       452: operator is used.
                    453: .Pp
1.102     sjg       454: If the first characters of the command line are any combination of
                    455: .Ql Ic @ ,
1.103     wiz       456: .Ql Ic + ,
1.102     sjg       457: or
1.1       cgd       458: .Ql Ic \- ,
                    459: the command is treated specially.
                    460: A
                    461: .Ql Ic @
                    462: causes the command not to be echoed before it is executed.
                    463: A
1.102     sjg       464: .Ql Ic +
                    465: causes the command to be executed even when
                    466: .Fl n
                    467: is given.
                    468: This is similar to the effect of the .MAKE special source,
                    469: except that the effect can be limited to a single line of a script.
                    470: A
1.1       cgd       471: .Ql Ic \-
                    472: causes any non-zero exit status of the command line to be ignored.
1.210     sjg       473: .Pp
                    474: When
                    475: .Nm
                    476: is run in jobs mode with
                    477: .Fl j Ar max_jobs ,
                    478: the entire script for the target is fed to a
                    479: single instance of the shell.
                    480: .Pp
                    481: In compatibility (non-jobs) mode, each command is run in a separate process.
                    482: If the command contains any shell meta characters
                    483: .Pq Ql #=|^(){};&<>*?[]:$`\e\en
                    484: it will be passed to the shell, otherwise
                    485: .Nm
                    486: will attempt direct execution.
                    487: .Pp
                    488: Since
                    489: .Nm
                    490: will
                    491: .Xr chdir 2
                    492: to
                    493: .Ql Va .OBJDIR
                    494: before executing any targets, each child process
                    495: starts with that as its current working directory.
                    496: .Pp
                    497: Makefiles should be written so that the mode of
                    498: .Nm
                    499: operation does not change their behavior.
                    500: For example, any command which needs to use
                    501: .Dq cd
                    502: or
1.237     dholland  503: .Dq chdir ,
                    504: without side-effect should be put in parenthesis:
1.210     sjg       505: .Bd -literal -offset indent
                    506:
                    507: avoid-chdir-side-effects:
                    508:        @echo Building $@ in `pwd`
1.237     dholland  509:        @(cd ${.CURDIR} && ${.MAKE} $@)
1.210     sjg       510:        @echo Back in `pwd`
                    511:
                    512: ensure-one-shell-regardless-of-mode:
                    513:        @echo Building $@ in `pwd`; \\
1.237     dholland  514:        (cd ${.CURDIR} && ${.MAKE} $@); \\
1.210     sjg       515:        echo Back in `pwd`
                    516: .Ed
1.1       cgd       517: .Sh VARIABLE ASSIGNMENTS
                    518: Variables in make are much like variables in the shell, and, by tradition,
                    519: consist of all upper-case letters.
1.91      lukem     520: .Ss Variable assignment modifiers
1.1       cgd       521: The five operators that can be used to assign values to variables are as
                    522: follows:
                    523: .Bl -tag -width Ds
                    524: .It Ic \&=
                    525: Assign the value to the variable.
                    526: Any previous value is overridden.
                    527: .It Ic \&+=
                    528: Append the value to the current value of the variable.
                    529: .It Ic \&?=
                    530: Assign the value to the variable if it is not already defined.
                    531: .It Ic \&:=
                    532: Assign with expansion, i.e. expand the value before assigning it
                    533: to the variable.
                    534: Normally, expansion is not done until the variable is referenced.
1.124     sjg       535: .Em NOTE :
                    536: References to undefined variables are
                    537: .Em not
1.125     wiz       538: expanded.
                    539: This can cause problems when variable modifiers are used.
1.1       cgd       540: .It Ic \&!=
                    541: Expand the value and pass it to the shell for execution and assign
                    542: the result to the variable.
                    543: Any newlines in the result are replaced with spaces.
                    544: .El
                    545: .Pp
                    546: Any white-space before the assigned
                    547: .Ar value
                    548: is removed; if the value is being appended, a single space is inserted
                    549: between the previous contents of the variable and the appended value.
                    550: .Pp
                    551: Variables are expanded by surrounding the variable name with either
                    552: curly braces
                    553: .Pq Ql {}
1.7       mycroft   554: or parentheses
1.1       cgd       555: .Pq Ql ()
                    556: and preceding it with
                    557: a dollar sign
                    558: .Pq Ql \&$ .
                    559: If the variable name contains only a single letter, the surrounding
1.7       mycroft   560: braces or parentheses are not required.
1.1       cgd       561: This shorter form is not recommended.
                    562: .Pp
1.149     dsl       563: If the variable name contains a dollar, then the name itself is expanded first.
                    564: This allows almost arbitrary variable names, however names containing dollar,
                    565: braces, parenthesis, or whitespace are really best avoided!
                    566: .Pp
                    567: If the result of expanding a variable contains a dollar sign
                    568: .Pq Ql \&$
                    569: the string is expanded again.
                    570: .Pp
1.175     christos  571: Variable substitution occurs at three distinct times, depending on where
1.1       cgd       572: the variable is being used.
1.175     christos  573: .Bl -enum
1.176     wiz       574: .It
1.1       cgd       575: Variables in dependency lines are expanded as the line is read.
1.175     christos  576: .It
1.1       cgd       577: Variables in shell commands are expanded when the shell command is
                    578: executed.
1.175     christos  579: .It
                    580: .Dq .for
1.176     wiz       581: loop index variables are expanded on each loop iteration.
                    582: Note that other variables are not expanded inside loops so
1.175     christos  583: the following example code:
                    584: .Bd -literal -offset indent
                    585:
                    586: .Dv .for i in 1 2 3
                    587: a+=     ${i}
                    588: j=      ${i}
                    589: b+=     ${j}
                    590: .Dv .endfor
                    591:
                    592: all:
1.176     wiz       593:        @echo ${a}
1.175     christos  594:        @echo ${b}
                    595:
                    596: .Ed
                    597: will print:
                    598: .Bd -literal -offset indent
                    599: 1 2 3
                    600: 3 3 3
                    601:
                    602: .Ed
                    603: Because while ${a} contains
                    604: .Dq 1 2 3
                    605: after the loop is executed, ${b}
                    606: contains
                    607: .Dq ${j} ${j} ${j}
                    608: which expands to
                    609: .Dq 3 3 3
                    610: since after the loop completes ${j} contains
                    611: .Dq 3 .
                    612: .El
1.91      lukem     613: .Ss Variable classes
1.1       cgd       614: The four different classes of variables (in order of increasing precedence)
                    615: are:
                    616: .Bl -tag -width Ds
                    617: .It Environment variables
                    618: Variables defined as part of
1.74      wiz       619: .Nm Ns 's
1.1       cgd       620: environment.
                    621: .It Global variables
                    622: Variables defined in the makefile or in included makefiles.
                    623: .It Command line variables
                    624: Variables defined as part of the command line.
                    625: .It Local variables
1.237     dholland  626: Variables that are defined specific to a certain target.
                    627: The seven local variables are as follows:
1.1       cgd       628: .Bl -tag -width ".ARCHIVE"
                    629: .It Va .ALLSRC
                    630: The list of all sources for this target; also known as
1.62      ross      631: .Ql Va \&\*[Gt] .
1.1       cgd       632: .It Va .ARCHIVE
1.237     dholland  633: The name of the archive file.
1.1       cgd       634: .It Va .IMPSRC
1.237     dholland  635: In suffix-transformation rules, the name/path of the source from which the
1.137     wiz       636: target is to be transformed (the
                    637: .Dq implied
1.237     dholland  638: source); also known as
1.62      ross      639: .Ql Va \&\*[Lt] .
1.237     dholland  640: It is not defined in explicit rules.
1.1       cgd       641: .It Va .MEMBER
1.237     dholland  642: The name of the archive member.
1.1       cgd       643: .It Va .OODATE
                    644: The list of sources for this target that were deemed out-of-date; also
                    645: known as
                    646: .Ql Va \&? .
                    647: .It Va .PREFIX
1.177     dholland  648: The file prefix of the target, containing only the file portion, no suffix
1.1       cgd       649: or preceding directory components; also known as
                    650: .Ql Va * .
                    651: .It Va .TARGET
                    652: The name of the target; also known as
                    653: .Ql Va @ .
                    654: .El
                    655: .Pp
1.237     dholland  656: The shorter forms
                    657: .Ql Va @ ,
1.80      wiz       658: .Ql Va \&? ,
1.237     dholland  659: .Ql Va \&\*[Lt] ,
                    660: .Ql Va \&\*[Gt] ,
1.1       cgd       661: and
1.237     dholland  662: .Ql Va *
                    663: are permitted for backward
                    664: compatibility with historical makefiles and are not recommended.
                    665: The six variables
                    666: .Ql Va "@F" ,
                    667: .Ql Va "@D" ,
                    668: .Ql Va "\*[Lt]F" ,
                    669: .Ql Va "\*[Lt]D" ,
                    670: .Ql Va "*F" ,
1.1       cgd       671: and
1.237     dholland  672: .Ql Va "*D"
                    673: are permitted for compatibility with
                    674: .At V
                    675: makefiles and are not recommended.
1.1       cgd       676: .Pp
                    677: Four of the local variables may be used in sources on dependency lines
                    678: because they expand to the proper value for each target on the line.
                    679: These variables are
                    680: .Ql Va .TARGET ,
                    681: .Ql Va .PREFIX ,
                    682: .Ql Va .ARCHIVE ,
                    683: and
                    684: .Ql Va .MEMBER .
1.59      bgrayson  685: .El
1.145     christos  686: .Ss Additional built-in variables
1.1       cgd       687: In addition,
1.25      lukem     688: .Nm
1.1       cgd       689: sets or knows about the following variables:
1.50      sjg       690: .Bl -tag -width .MAKEOVERRIDES
1.1       cgd       691: .It Va \&$
                    692: A single dollar sign
                    693: .Ql \&$ ,
                    694: i.e.
                    695: .Ql \&$$
                    696: expands to a single dollar
                    697: sign.
1.56      tv        698: .It Va .ALLTARGETS
1.67      grant     699: The list of all targets encountered in the Makefile.
                    700: If evaluated during
1.56      tv        701: Makefile parsing, lists only those targets encountered thus far.
1.1       cgd       702: .It Va .CURDIR
                    703: A path to the directory where
1.25      lukem     704: .Nm
1.1       cgd       705: was executed.
1.117     lukem     706: Refer to the description of
                    707: .Ql Ev PWD
                    708: for more details.
1.230     sjg       709: .It Va .INCLUDEDFROMDIR
                    710: The directory of the file this Makefile was included from.
                    711: .It Va .INCLUDEDFROMFILE
                    712: The filename of the file this Makefile was included from.
1.78      christos  713: .It Ev MAKE
1.55      tv        714: The name that
                    715: .Nm
1.89      sjg       716: was executed with
                    717: .Pq Va argv[0] .
1.126     reed      718: For compatibility
1.78      christos  719: .Nm
                    720: also sets
                    721: .Va .MAKE
                    722: with the same value.
1.97      lukem     723: The preferred variable to use is the environment variable
1.78      christos  724: .Ev MAKE
                    725: because it is more compatible with other versions of
                    726: .Nm
                    727: and cannot be confused with the special target with the same name.
1.168     sjg       728: .It Va .MAKE.DEPENDFILE
1.169     wiz       729: Names the makefile (default
1.168     sjg       730: .Ql Pa .depend )
                    731: from which generated dependencies are read.
1.205     sjg       732: .It Va .MAKE.EXPAND_VARIABLES
                    733: A boolean that controls the default behavior of the
                    734: .Fl V
                    735: option.
1.134     sjg       736: .It Va .MAKE.EXPORTED
                    737: The list of variables exported by
                    738: .Nm .
1.171     sjg       739: .It Va .MAKE.JOBS
1.172     joerg     740: The argument to the
1.171     sjg       741: .Fl j
                    742: option.
1.132     sjg       743: .It Va .MAKE.JOB.PREFIX
1.137     wiz       744: If
1.132     sjg       745: .Nm
                    746: is run with
                    747: .Ar j
1.137     wiz       748: then output for each target is prefixed with a token
1.132     sjg       749: .Ql --- target ---
                    750: the first part of which can be controlled via
                    751: .Va .MAKE.JOB.PREFIX .
1.225     wiz       752: If
1.220     sjg       753: .Va .MAKE.JOB.PREFIX
                    754: is empty, no token is printed.
1.132     sjg       755: .br
1.137     wiz       756: For example:
1.132     sjg       757: .Li .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}]
                    758: would produce tokens like
                    759: .Ql ---make[1234] target ---
                    760: making it easier to track the degree of parallelism being achieved.
1.1       cgd       761: .It Ev MAKEFLAGS
                    762: The environment variable
                    763: .Ql Ev MAKEFLAGS
                    764: may contain anything that
                    765: may be specified on
1.74      wiz       766: .Nm Ns 's
1.1       cgd       767: command line.
                    768: Anything specified on
1.74      wiz       769: .Nm Ns 's
1.1       cgd       770: command line is appended to the
                    771: .Ql Ev MAKEFLAGS
                    772: variable which is then
                    773: entered into the environment for all programs which
1.25      lukem     774: .Nm
1.1       cgd       775: executes.
1.169     wiz       776: .It Va .MAKE.LEVEL
                    777: The recursion depth of
                    778: .Nm .
                    779: The initial instance of
                    780: .Nm
                    781: will be 0, and an incremented value is put into the environment
                    782: to be seen by the next generation.
                    783: This allows tests like:
                    784: .Li .if ${.MAKE.LEVEL} == 0
                    785: to protect things which should only be evaluated in the initial instance of
                    786: .Nm .
                    787: .It Va .MAKE.MAKEFILE_PREFERENCE
                    788: The ordered list of makefile names
                    789: (default
                    790: .Ql Pa makefile ,
                    791: .Ql Pa Makefile )
                    792: that
                    793: .Nm
                    794: will look for.
                    795: .It Va .MAKE.MAKEFILES
                    796: The list of makefiles read by
                    797: .Nm ,
                    798: which is useful for tracking dependencies.
1.204     sjg       799: Each makefile is recorded only once, regardless of the number of times read.
1.169     wiz       800: .It Va .MAKE.MODE
                    801: Processed after reading all makefiles.
                    802: Can affect the mode that
                    803: .Nm
                    804: runs in.
1.180     sjg       805: It can contain a number of keywords:
                    806: .Bl -hang -width ignore-cmd
                    807: .It Pa compat
1.182     wiz       808: Like
1.184     sjg       809: .Fl B ,
1.182     wiz       810: puts
1.180     sjg       811: .Nm
                    812: into "compat" mode.
                    813: .It Pa meta
                    814: Puts
                    815: .Nm
1.182     wiz       816: into "meta" mode, where meta files are created for each target
1.180     sjg       817: to capture the command run, the output generated and if
                    818: .Xr filemon 4
                    819: is available, the system calls which are of interest to
                    820: .Nm .
                    821: The captured output can be very useful when diagnosing errors.
1.185     sjg       822: .It Pa curdirOk= Ar bf
1.184     sjg       823: Normally
                    824: .Nm
                    825: will not create .meta files in
                    826: .Ql Va .CURDIR .
                    827: This can be overridden by setting
1.188     wiz       828: .Va bf
1.184     sjg       829: to a value which represents True.
1.200     sjg       830: .It Pa env
                    831: For debugging, it can be useful to inlcude the environment
                    832: in the .meta file.
1.180     sjg       833: .It Pa verbose
                    834: If in "meta" mode, print a clue about the target being built.
                    835: This is useful if the build is otherwise running silently.
                    836: The message printed the value of:
                    837: .Va .MAKE.META.PREFIX .
                    838: .It Pa ignore-cmd
                    839: Some makefiles have commands which are simply not stable.
1.182     wiz       840: This keyword causes them to be ignored for
1.180     sjg       841: determining whether a target is out of date in "meta" mode.
                    842: See also
                    843: .Ic .NOMETA_CMP .
1.195     sjg       844: .It Pa silent= Ar bf
                    845: If
                    846: .Va bf
                    847: is True, when a .meta file is created, mark the target
1.200     sjg       848: .Ic .SILENT .
1.180     sjg       849: .El
1.189     sjg       850: .It Va .MAKE.META.BAILIWICK
                    851: In "meta" mode, provides a list of prefixes which
                    852: match the directories controlled by
                    853: .Nm .
                    854: If a file that was generated outside of
                    855: .Va .OBJDIR
                    856: but within said bailiwick is missing,
                    857: the current target is considered out-of-date.
1.180     sjg       858: .It Va .MAKE.META.CREATED
                    859: In "meta" mode, this variable contains a list of all the meta files
                    860: updated.
                    861: If not empty, it can be used to trigger processing of
                    862: .Va .MAKE.META.FILES .
                    863: .It Va .MAKE.META.FILES
                    864: In "meta" mode, this variable contains a list of all the meta files
                    865: used (updated or not).
1.182     wiz       866: This list can be used to process the meta files to extract dependency
1.180     sjg       867: information.
1.216     sjg       868: .It Va .MAKE.META.IGNORE_PATHS
                    869: Provides a list of path prefixes that should be ignored;
                    870: because the contents are expected to change over time.
                    871: The default list includes:
                    872: .Ql Pa /dev /etc /proc /tmp /var/run /var/tmp
1.180     sjg       873: .It Va .MAKE.META.PREFIX
                    874: Defines the message printed for each meta file updated in "meta verbose" mode.
                    875: The default value is:
                    876: .Dl Building ${.TARGET:H:tA}/${.TARGET:T}
1.50      sjg       877: .It Va .MAKEOVERRIDES
1.57      wiz       878: This variable is used to record the names of variables assigned to
                    879: on the command line, so that they may be exported as part of
1.50      sjg       880: .Ql Ev MAKEFLAGS .
1.57      wiz       881: This behaviour can be disabled by assigning an empty value to
1.50      sjg       882: .Ql Va .MAKEOVERRIDES
1.67      grant     883: within a makefile.
                    884: Extra variables can be exported from a makefile
1.57      wiz       885: by appending their names to
1.51      sjg       886: .Ql Va .MAKEOVERRIDES .
                    887: .Ql Ev MAKEFLAGS
1.57      wiz       888: is re-exported whenever
1.51      sjg       889: .Ql Va .MAKEOVERRIDES
                    890: is modified.
1.212     sjg       891: .It Va .MAKE.PATH_FILEMON
                    892: If
                    893: .Nm
1.217     wiz       894: was built with
1.212     sjg       895: .Xr filemon 4
                    896: support, this is set to the path of the device node.
                    897: This allows makefiles to test for this support.
1.169     wiz       898: .It Va .MAKE.PID
                    899: The process-id of
                    900: .Nm .
                    901: .It Va .MAKE.PPID
                    902: The parent process-id of
                    903: .Nm .
1.55      tv        904: .It Va MAKE_PRINT_VAR_ON_ERROR
1.57      wiz       905: When
1.55      tv        906: .Nm
                    907: stops due to an error, it prints its name and the value of
                    908: .Ql Va .CURDIR
1.57      wiz       909: as well as the value of any variables named in
1.55      tv        910: .Ql Va MAKE_PRINT_VAR_ON_ERROR .
                    911: .It Va .newline
                    912: This variable is simply assigned a newline character as its value.
1.91      lukem     913: This allows expansions using the
                    914: .Cm \&:@
                    915: modifier to put a newline between
1.67      grant     916: iterations of the loop rather than a space.
                    917: For example, the printing of
1.55      tv        918: .Ql Va MAKE_PRINT_VAR_ON_ERROR
                    919: could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}.
                    920: .It Va .OBJDIR
                    921: A path to the directory where the targets are built.
1.117     lukem     922: Its value is determined by trying to
                    923: .Xr chdir 2
                    924: to the following directories in order and using the first match:
                    925: .Bl -enum
                    926: .It
1.118     wiz       927: .Ev ${MAKEOBJDIRPREFIX}${.CURDIR}
                    928: .Pp
1.117     lukem     929: (Only if
                    930: .Ql Ev MAKEOBJDIRPREFIX
                    931: is set in the environment or on the command line.)
                    932: .It
1.118     wiz       933: .Ev ${MAKEOBJDIR}
                    934: .Pp
1.117     lukem     935: (Only if
                    936: .Ql Ev MAKEOBJDIR
                    937: is set in the environment or on the command line.)
                    938: .It
                    939: .Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE}
                    940: .It
                    941: .Ev ${.CURDIR} Ns Pa /obj
                    942: .It
                    943: .Pa /usr/obj/ Ns Ev ${.CURDIR}
                    944: .It
                    945: .Ev ${.CURDIR}
                    946: .El
                    947: .Pp
                    948: Variable expansion is performed on the value before it's used,
                    949: so expressions such as
1.173     sjg       950: .Dl ${.CURDIR:S,^/usr/src,/var/obj,}
1.117     lukem     951: may be used.
1.173     sjg       952: This is especially useful with
                    953: .Ql Ev MAKEOBJDIR .
1.117     lukem     954: .Pp
                    955: .Ql Va .OBJDIR
                    956: may be modified in the makefile as a global variable.
1.137     wiz       957: In all cases,
1.117     lukem     958: .Nm
                    959: will
                    960: .Xr chdir 2
                    961: to
                    962: .Ql Va .OBJDIR
                    963: and set
                    964: .Ql Ev PWD
                    965: to that directory before executing any targets.
                    966: .
1.55      tv        967: .It Va .PARSEDIR
                    968: A path to the directory of the current
                    969: .Ql Pa Makefile
                    970: being parsed.
                    971: .It Va .PARSEFILE
                    972: The basename of the current
                    973: .Ql Pa Makefile
                    974: being parsed.
                    975: This variable and
                    976: .Ql Va .PARSEDIR
                    977: are both set only while the
                    978: .Ql Pa Makefiles
                    979: are being parsed.
1.196     christos  980: If you want to retain their current values, assign them to a variable
                    981: using assignment with expansion:
                    982: .Pq Ql Cm \&:= .
1.69      sjg       983: .It Va .PATH
1.82      wiz       984: A variable that represents the list of directories that
1.69      sjg       985: .Nm
1.70      wiz       986: will search for files.
                    987: The search list should be updated using the target
1.69      sjg       988: .Ql Va .PATH
                    989: rather than the variable.
1.16      christos  990: .It Ev PWD
                    991: Alternate path to the current directory.
1.25      lukem     992: .Nm
1.16      christos  993: normally sets
                    994: .Ql Va .CURDIR
                    995: to the canonical path given by
1.48      wiz       996: .Xr getcwd 3 .
1.16      christos  997: However, if the environment variable
                    998: .Ql Ev PWD
                    999: is set and gives a path to the current directory, then
1.25      lukem    1000: .Nm
1.16      christos 1001: sets
                   1002: .Ql Va .CURDIR
                   1003: to the value of
                   1004: .Ql Ev PWD
1.67      grant    1005: instead.
                   1006: This behaviour is disabled if
1.40      sjg      1007: .Ql Ev MAKEOBJDIRPREFIX
1.117     lukem    1008: is set or
                   1009: .Ql Ev MAKEOBJDIR
                   1010: contains a variable transform.
1.16      christos 1011: .Ql Ev PWD
                   1012: is set to the value of
                   1013: .Ql Va .OBJDIR
                   1014: for all programs which
1.25      lukem    1015: .Nm
1.16      christos 1016: executes.
1.179     dholland 1017: .It Ev .TARGETS
                   1018: The list of targets explicitly specified on the command line, if any.
1.145     christos 1019: .It Ev VPATH
1.146     wiz      1020: Colon-separated
                   1021: .Pq Dq \&:
                   1022: lists of directories that
                   1023: .Nm
                   1024: will search for files.
1.145     christos 1025: The variable is supported for compatibility with old make programs only,
                   1026: use
                   1027: .Ql Va .PATH
                   1028: instead.
1.1       cgd      1029: .El
1.91      lukem    1030: .Ss Variable modifiers
1.1       cgd      1031: Variable expansion may be modified to select or modify each word of the
1.137     wiz      1032: variable (where a
                   1033: .Dq word
                   1034: is white-space delimited sequence of characters).
1.1       cgd      1035: The general format of a variable expansion is as follows:
                   1036: .Pp
1.120     sjg      1037: .Dl ${variable[:modifier[:...]]}
1.1       cgd      1038: .Pp
1.97      lukem    1039: Each modifier begins with a colon,
                   1040: which may be escaped with a backslash
1.1       cgd      1041: .Pq Ql \e .
1.120     sjg      1042: .Pp
                   1043: A set of modifiers can be specified via a variable, as follows:
                   1044: .Pp
                   1045: .Dl modifier_variable=modifier[:...]
                   1046: .Dl ${variable:${modifier_variable}[:...]}
                   1047: .Pp
                   1048: In this case the first modifier in the modifier_variable does not
                   1049: start with a colon, since that must appear in the referencing
                   1050: variable.
                   1051: If any of the modifiers in the modifier_variable contain a dollar sign
                   1052: .Pq Ql $ ,
                   1053: these must be doubled to avoid early expansion.
                   1054: .Pp
1.97      lukem    1055: The supported modifiers are:
1.61      ross     1056: .Bl -tag -width EEE
1.91      lukem    1057: .It Cm \&:E
1.1       cgd      1058: Replaces each word in the variable with its suffix.
1.91      lukem    1059: .It Cm \&:H
1.237     dholland 1060: Replaces each word in the variable with everything but the last component.
1.91      lukem    1061: .It Cm \&:M Ns Ar pattern
1.72      uebayasi 1062: Select only those words that match
                   1063: .Ar pattern .
1.1       cgd      1064: The standard shell wildcard characters
                   1065: .Pf ( Ql * ,
1.80      wiz      1066: .Ql \&? ,
1.1       cgd      1067: and
1.172     joerg    1068: .Ql Oo Oc )
1.1       cgd      1069: may
                   1070: be used.
                   1071: The wildcard characters may be escaped with a backslash
                   1072: .Pq Ql \e .
1.224     apb      1073: As a consequence of the way values are split into words, matched,
                   1074: and then joined, a construct like
                   1075: .Dl ${VAR:M*}
                   1076: will normalise the inter-word spacing, removing all leading and
                   1077: trailing space, and converting multiple consecutive spaces
                   1078: to single spaces.
                   1079: .
1.91      lukem    1080: .It Cm \&:N Ns Ar pattern
1.1       cgd      1081: This is identical to
1.91      lukem    1082: .Ql Cm \&:M ,
1.1       cgd      1083: but selects all words which do not match
1.72      uebayasi 1084: .Ar pattern .
1.91      lukem    1085: .It Cm \&:O
1.109     wiz      1086: Order every word in variable alphabetically.
                   1087: To sort words in
                   1088: reverse order use the
1.108     sjg      1089: .Ql Cm \&:O:[-1..1]
                   1090: combination of modifiers.
                   1091: .It Cm \&:Ox
1.109     wiz      1092: Randomize words in variable.
                   1093: The results will be different each time you are referring to the
                   1094: modified variable; use the assignment with expansion
1.108     sjg      1095: .Pq Ql Cm \&:=
1.109     wiz      1096: to prevent such behaviour.
                   1097: For example,
1.108     sjg      1098: .Bd -literal -offset indent
                   1099: LIST=                  uno due tre quattro
                   1100: RANDOM_LIST=           ${LIST:Ox}
                   1101: STATIC_RANDOM_LIST:=   ${LIST:Ox}
                   1102:
                   1103: all:
                   1104:        @echo "${RANDOM_LIST}"
                   1105:        @echo "${RANDOM_LIST}"
                   1106:        @echo "${STATIC_RANDOM_LIST}"
                   1107:        @echo "${STATIC_RANDOM_LIST}"
                   1108: .Ed
1.109     wiz      1109: may produce output similar to:
1.108     sjg      1110: .Bd -literal -offset indent
                   1111: quattro due tre uno
                   1112: tre due quattro uno
                   1113: due uno quattro tre
                   1114: due uno quattro tre
                   1115: .Ed
1.91      lukem    1116: .It Cm \&:Q
1.17      christos 1117: Quotes every shell meta-character in the variable, so that it can be passed
                   1118: safely through recursive invocations of
1.74      wiz      1119: .Nm .
1.91      lukem    1120: .It Cm \&:R
1.1       cgd      1121: Replaces each word in the variable with everything but its suffix.
1.187     sjg      1122: .It Cm \&:gmtime
1.188     wiz      1123: The value is a format string for
1.187     sjg      1124: .Xr strftime 3 ,
1.188     wiz      1125: using the current
1.187     sjg      1126: .Xr gmtime 3 .
1.186     joerg    1127: .It Cm \&:hash
                   1128: Compute a 32bit hash of the value and encode it as hex digits.
1.187     sjg      1129: .It Cm \&:localtime
1.188     wiz      1130: The value is a format string for
1.187     sjg      1131: .Xr strftime 3 ,
1.188     wiz      1132: using the current
1.187     sjg      1133: .Xr localtime 3 .
1.170     sjg      1134: .It Cm \&:tA
                   1135: Attempt to convert variable to an absolute path using
                   1136: .Xr realpath 3 ,
                   1137: if that fails, the value is unchanged.
1.91      lukem    1138: .It Cm \&:tl
1.60      pk       1139: Converts variable to lower-case letters.
1.91      lukem    1140: .It Cm \&:ts Ns Ar c
1.81      sjg      1141: Words in the variable are normally separated by a space on expansion.
                   1142: This modifier sets the separator to the character
                   1143: .Ar c .
                   1144: If
                   1145: .Ar c
                   1146: is omitted, then no separator is used.
1.170     sjg      1147: The common escapes (including octal numeric codes), work as expected.
1.91      lukem    1148: .It Cm \&:tu
1.82      wiz      1149: Converts variable to upper-case letters.
1.91      lukem    1150: .It Cm \&:tW
1.89      sjg      1151: Causes the value to be treated as a single word
                   1152: (possibly containing embedded white space).
                   1153: See also
1.91      lukem    1154: .Ql Cm \&:[*] .
                   1155: .It Cm \&:tw
1.89      sjg      1156: Causes the value to be treated as a sequence of
                   1157: words delimited by white space.
                   1158: See also
1.91      lukem    1159: .Ql Cm \&:[@] .
1.1       cgd      1160: .Sm off
1.164     joerg    1161: .It Cm \&:S No \&/ Ar old_string No \&/ Ar new_string No \&/ Op Cm 1gW
1.1       cgd      1162: .Sm on
                   1163: Modify the first occurrence of
1.17      christos 1164: .Ar old_string
                   1165: in the variable's value, replacing it with
                   1166: .Ar new_string .
1.1       cgd      1167: If a
                   1168: .Ql g
                   1169: is appended to the last slash of the pattern, all occurrences
                   1170: in each word are replaced.
1.17      christos 1171: If a
                   1172: .Ql 1
                   1173: is appended to the last slash of the pattern, only the first word
                   1174: is affected.
1.89      sjg      1175: If a
                   1176: .Ql W
                   1177: is appended to the last slash of the pattern,
                   1178: then the value is treated as a single word
                   1179: (possibly containing embedded white space).
1.1       cgd      1180: If
1.17      christos 1181: .Ar old_string
                   1182: begins with a caret
1.1       cgd      1183: .Pq Ql ^ ,
1.17      christos 1184: .Ar old_string
1.1       cgd      1185: is anchored at the beginning of each word.
                   1186: If
1.17      christos 1187: .Ar old_string
1.1       cgd      1188: ends with a dollar sign
                   1189: .Pq Ql \&$ ,
                   1190: it is anchored at the end of each word.
                   1191: Inside
                   1192: .Ar new_string ,
                   1193: an ampersand
1.62      ross     1194: .Pq Ql \*[Am]
1.1       cgd      1195: is replaced by
1.17      christos 1196: .Ar old_string
                   1197: (without any
                   1198: .Ql ^
                   1199: or
                   1200: .Ql \&$ ) .
1.1       cgd      1201: Any character may be used as a delimiter for the parts of the modifier
                   1202: string.
                   1203: The anchoring, ampersand and delimiter characters may be escaped with a
                   1204: backslash
                   1205: .Pq Ql \e .
                   1206: .Pp
                   1207: Variable expansion occurs in the normal fashion inside both
                   1208: .Ar old_string
                   1209: and
                   1210: .Ar new_string
                   1211: with the single exception that a backslash is used to prevent the expansion
                   1212: of a dollar sign
1.17      christos 1213: .Pq Ql \&$ ,
1.1       cgd      1214: not a preceding dollar sign as is usual.
1.17      christos 1215: .Sm off
1.164     joerg    1216: .It Cm \&:C No \&/ Ar pattern No \&/ Ar replacement No \&/ Op Cm 1gW
1.17      christos 1217: .Sm on
                   1218: The
1.91      lukem    1219: .Cm \&:C
1.17      christos 1220: modifier is just like the
1.91      lukem    1221: .Cm \&:S
1.37      msaitoh  1222: modifier except that the old and new strings, instead of being
1.223     apb      1223: simple strings, are an extended regular expression (see
1.17      christos 1224: .Xr regex 3 )
1.72      uebayasi 1225: string
                   1226: .Ar pattern
1.17      christos 1227: and an
                   1228: .Xr ed 1 Ns \-style
1.72      uebayasi 1229: string
                   1230: .Ar replacement .
                   1231: Normally, the first occurrence of the pattern
                   1232: .Ar pattern
                   1233: in each word of the value is substituted with
                   1234: .Ar replacement .
1.67      grant    1235: The
1.17      christos 1236: .Ql 1
                   1237: modifier causes the substitution to apply to at most one word; the
                   1238: .Ql g
                   1239: modifier causes the substitution to apply to as many instances of the
1.72      uebayasi 1240: search pattern
                   1241: .Ar pattern
1.89      sjg      1242: as occur in the word or words it is found in; the
                   1243: .Ql W
                   1244: modifier causes the value to be treated as a single word
                   1245: (possibly containing embedded white space).
1.67      grant    1246: Note that
1.17      christos 1247: .Ql 1
                   1248: and
                   1249: .Ql g
                   1250: are orthogonal; the former specifies whether multiple words are
                   1251: potentially affected, the latter whether multiple substitutions can
                   1252: potentially occur within each affected word.
1.229     apb      1253: .Pp
                   1254: As for the
                   1255: .Cm \&:S
                   1256: modifier, the
                   1257: .Ar pattern
                   1258: and
                   1259: .Ar replacement
                   1260: are subjected to variable expansion before being parsed as
                   1261: regular expressions.
1.91      lukem    1262: .It Cm \&:T
1.237     dholland 1263: Replaces each word in the variable with its last component.
1.91      lukem    1264: .It Cm \&:u
1.43      christos 1265: Remove adjacent duplicate words (like
1.57      wiz      1266: .Xr uniq 1 ) .
1.91      lukem    1267: .Sm off
                   1268: .It Cm \&:\&? Ar true_string Cm \&: Ar false_string
                   1269: .Sm on
1.152     dsl      1270: If the variable name (not its value), when parsed as a .if conditional
                   1271: expression, evaluates to true, return as its value the
1.57      wiz      1272: .Ar true_string ,
1.27      christos 1273: otherwise return the
1.57      wiz      1274: .Ar false_string .
1.152     dsl      1275: Since the variable name is used as the expression, \&:\&? must be the
                   1276: first modifier after the variable name itself - which will, of course,
                   1277: usually contain variable expansions.
1.162     dsl      1278: A common error is trying to use expressions like
                   1279: .Dl ${NUMBERS:M42:?match:no}
                   1280: which actually tests defined(NUMBERS),
                   1281: to determine is any words match "42" you need to use something like:
1.183     sjg      1282: .Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} .
1.91      lukem    1283: .It Ar :old_string=new_string
1.1       cgd      1284: This is the
                   1285: .At V
1.237     dholland 1286: style variable substitution.
1.1       cgd      1287: It must be the last modifier specified.
1.16      christos 1288: If
1.6       cgd      1289: .Ar old_string
                   1290: or
                   1291: .Ar new_string
                   1292: do not contain the pattern matching character
                   1293: .Ar %
1.16      christos 1294: then it is assumed that they are
1.6       cgd      1295: anchored at the end of each word, so only suffixes or entire
1.67      grant    1296: words may be replaced.
                   1297: Otherwise
1.6       cgd      1298: .Ar %
1.16      christos 1299: is the substring of
                   1300: .Ar old_string
1.6       cgd      1301: to be replaced in
1.64      wiz      1302: .Ar new_string .
1.95      jmc      1303: .Pp
                   1304: Variable expansion occurs in the normal fashion inside both
                   1305: .Ar old_string
                   1306: and
                   1307: .Ar new_string
1.96      wiz      1308: with the single exception that a backslash is used to prevent the
                   1309: expansion of a dollar sign
                   1310: .Pq Ql \&$ ,
                   1311: not a preceding dollar sign as is usual.
1.91      lukem    1312: .Sm off
1.164     joerg    1313: .It Cm \&:@ Ar temp Cm @ Ar string Cm @
1.91      lukem    1314: .Sm on
1.40      sjg      1315: This is the loop expansion mechanism from the OSF Development
1.67      grant    1316: Environment (ODE) make.
                   1317: Unlike
1.48      wiz      1318: .Cm \&.for
1.40      sjg      1319: loops expansion occurs at the time of
1.67      grant    1320: reference.
                   1321: Assign
1.40      sjg      1322: .Ar temp
                   1323: to each word in the variable and evaluate
                   1324: .Ar string .
1.48      wiz      1325: The ODE convention is that
1.40      sjg      1326: .Ar temp
1.67      grant    1327: should start and end with a period.
                   1328: For example.
1.40      sjg      1329: .Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
1.198     sjg      1330: .Pp
1.218     agc      1331: However a single character variable is often more readable:
1.198     sjg      1332: .Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}
1.91      lukem    1333: .It Cm \&:U Ns Ar newval
1.40      sjg      1334: If the variable is undefined
                   1335: .Ar newval
1.63      lukem    1336: is the value.
                   1337: If the variable is defined, the existing value is returned.
1.67      grant    1338: This is another ODE make feature.
                   1339: It is handy for setting per-target CFLAGS for instance:
1.40      sjg      1340: .Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
1.63      lukem    1341: If a value is only required if the variable is undefined, use:
                   1342: .Dl ${VAR:D:Unewval}
1.91      lukem    1343: .It Cm \&:D Ns Ar newval
1.40      sjg      1344: If the variable is defined
                   1345: .Ar newval
                   1346: is the value.
1.91      lukem    1347: .It Cm \&:L
1.40      sjg      1348: The name of the variable is the value.
1.91      lukem    1349: .It Cm \&:P
1.40      sjg      1350: The path of the node which has the same name as the variable
1.67      grant    1351: is the value.
                   1352: If no such node exists or its path is null, then the
1.40      sjg      1353: name of the variable is used.
1.217     wiz      1354: In order for this modifier to work, the name (node) must at least have
1.199     sjg      1355: appeared on the rhs of a dependency.
1.91      lukem    1356: .Sm off
                   1357: .It Cm \&:\&! Ar cmd Cm \&!
                   1358: .Sm on
1.40      sjg      1359: The output of running
                   1360: .Ar cmd
                   1361: is the value.
1.91      lukem    1362: .It Cm \&:sh
1.40      sjg      1363: If the variable is non-empty it is run as a command and the output
                   1364: becomes the new value.
1.91      lukem    1365: .It Cm \&::= Ns Ar str
1.48      wiz      1366: The variable is assigned the value
1.41      sjg      1367: .Ar str
1.67      grant    1368: after substitution.
                   1369: This modifier and its variations are useful in
1.149     dsl      1370: obscure situations such as wanting to set a variable when shell commands
                   1371: are being parsed.
1.67      grant    1372: These assignment modifiers always expand to
1.41      sjg      1373: nothing, so if appearing in a rule line by themselves should be
1.48      wiz      1374: preceded with something to keep
1.41      sjg      1375: .Nm
1.67      grant    1376: happy.
1.149     dsl      1377: .Pp
1.91      lukem    1378: The
                   1379: .Ql Cm \&::
1.42      sjg      1380: helps avoid false matches with the
                   1381: .At V
1.48      wiz      1382: style
1.91      lukem    1383: .Cm \&:=
1.48      wiz      1384: modifier and since substitution always occurs the
1.91      lukem    1385: .Cm \&::=
1.42      sjg      1386: form is vaguely appropriate.
1.91      lukem    1387: .It Cm \&::?= Ns Ar str
1.41      sjg      1388: As for
1.91      lukem    1389: .Cm \&::=
1.41      sjg      1390: but only if the variable does not already have a value.
1.91      lukem    1391: .It Cm \&::+= Ns Ar str
1.48      wiz      1392: Append
1.41      sjg      1393: .Ar str
                   1394: to the variable.
1.91      lukem    1395: .It Cm \&::!= Ns Ar cmd
1.48      wiz      1396: Assign the output of
1.41      sjg      1397: .Ar cmd
                   1398: to the variable.
1.91      lukem    1399: .It Cm \&:\&[ Ns Ar range Ns Cm \&]
1.89      sjg      1400: Selects one or more words from the value,
                   1401: or performs other operations related to the way in which the
                   1402: value is divided into words.
                   1403: .Pp
                   1404: Ordinarily, a value is treated as a sequence of words
                   1405: delimited by white space.
                   1406: Some modifiers suppress this behaviour,
                   1407: causing a value to be treated as a single word
                   1408: (possibly containing embedded white space).
                   1409: An empty value, or a value that consists entirely of white-space,
                   1410: is treated as a single word.
                   1411: For the purposes of the
1.91      lukem    1412: .Ql Cm \&:[]
1.89      sjg      1413: modifier, the words are indexed both forwards using positive integers
                   1414: (where index 1 represents the first word),
                   1415: and backwards using negative integers
1.194     sjg      1416: (where index \-1 represents the last word).
1.89      sjg      1417: .Pp
                   1418: The
                   1419: .Ar range
                   1420: is subjected to variable expansion, and the expanded result is
                   1421: then interpreted as follows:
                   1422: .Bl -tag -width index
1.90      jdolecek 1423: .\" :[n]
1.89      sjg      1424: .It Ar index
                   1425: Selects a single word from the value.
1.90      jdolecek 1426: .\" :[start..end]
1.89      sjg      1427: .It Ar start Ns Cm \&.. Ns Ar end
                   1428: Selects all words from
                   1429: .Ar start
                   1430: to
                   1431: .Ar end ,
                   1432: inclusive.
                   1433: For example,
1.91      lukem    1434: .Ql Cm \&:[2..-1]
1.89      sjg      1435: selects all words from the second word to the last word.
                   1436: If
                   1437: .Ar start
                   1438: is greater than
                   1439: .Ar end ,
1.91      lukem    1440: then the words are output in reverse order.
                   1441: For example,
                   1442: .Ql Cm \&:[-1..1]
1.89      sjg      1443: selects all the words from last to first.
1.90      jdolecek 1444: .\" :[*]
1.89      sjg      1445: .It Cm \&*
                   1446: Causes subsequent modifiers to treat the value as a single word
1.109     wiz      1447: (possibly containing embedded white space).
                   1448: Analogous to the effect of
1.94      wiz      1449: \&"$*\&"
1.89      sjg      1450: in Bourne shell.
1.90      jdolecek 1451: .\" :[0]
1.89      sjg      1452: .It 0
                   1453: Means the same as
1.91      lukem    1454: .Ql Cm \&:[*] .
1.90      jdolecek 1455: .\" :[*]
1.89      sjg      1456: .It Cm \&@
                   1457: Causes subsequent modifiers to treat the value as a sequence of words
1.109     wiz      1458: delimited by white space.
                   1459: Analogous to the effect of
1.94      wiz      1460: \&"$@\&"
1.89      sjg      1461: in Bourne shell.
1.90      jdolecek 1462: .\" :[#]
1.89      sjg      1463: .It Cm \&#
                   1464: Returns the number of words in the value.
                   1465: .El \" :[range]
1.6       cgd      1466: .El
                   1467: .Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS
1.16      christos 1468: Makefile inclusion, conditional structures and for loops  reminiscent
1.6       cgd      1469: of the C programming language are provided in
1.74      wiz      1470: .Nm .
1.1       cgd      1471: All such structures are identified by a line beginning with a single
                   1472: dot
                   1473: .Pq Ql \&.
                   1474: character.
                   1475: Files are included with either
1.29      ross     1476: .Cm \&.include Aq Ar file
1.1       cgd      1477: or
1.29      ross     1478: .Cm \&.include Pf \*q Ar file Ns \*q .
1.1       cgd      1479: Variables between the angle brackets or double quotes are expanded
                   1480: to form the file name.
                   1481: If angle brackets are used, the included makefile is expected to be in
                   1482: the system makefile directory.
                   1483: If double quotes are used, the including makefile's directory and any
                   1484: directories specified using the
                   1485: .Fl I
                   1486: option are searched before the system
                   1487: makefile directory.
1.28      christos 1488: For compatibility with other versions of
                   1489: .Nm
                   1490: .Ql include file ...
1.67      grant    1491: is also accepted.
                   1492: If the include statement is written as
1.29      ross     1493: .Cm .-include
                   1494: or as
                   1495: .Cm .sinclude
1.28      christos 1496: then errors locating and/or opening include files are ignored.
1.1       cgd      1497: .Pp
                   1498: Conditional expressions are also preceded by a single dot as the first
1.5       jtc      1499: character of a line.
1.1       cgd      1500: The possible conditionals are as follows:
                   1501: .Bl -tag -width Ds
1.168     sjg      1502: .It Ic .error Ar message
                   1503: The message is printed along with the name of the makefile and line number,
                   1504: then
                   1505: .Nm
                   1506: will exit.
1.165     sjg      1507: .It Ic .export Ar variable ...
1.133     sjg      1508: Export the specified global variable.
1.165     sjg      1509: If no variable list is provided, all globals are exported
1.133     sjg      1510: except for internal variables (those that start with
1.157     wiz      1511: .Ql \&. ) .
1.133     sjg      1512: This is not affected by the
                   1513: .Fl X
                   1514: flag, so should be used with caution.
1.201     christos 1515: For compatibility with other
                   1516: .Nm
                   1517: programs
                   1518: .Ql export variable=value
                   1519: is also accepted.
1.165     sjg      1520: .Pp
1.133     sjg      1521: Appending a variable name to
                   1522: .Va .MAKE.EXPORTED
                   1523: is equivalent to exporting a variable.
1.173     sjg      1524: .It Ic .export-env Ar variable ...
1.176     wiz      1525: The same as
1.173     sjg      1526: .Ql .export ,
1.176     wiz      1527: except that the variable is not appended to
1.173     sjg      1528: .Va .MAKE.EXPORTED .
1.176     wiz      1529: This allows exporting a value to the environment which is different from that
                   1530: used by
1.173     sjg      1531: .Nm
                   1532: internally.
1.168     sjg      1533: .It Ic .info Ar message
                   1534: The message is printed along with the name of the makefile and line number.
1.169     wiz      1535: .It Ic .undef Ar variable
                   1536: Un-define the specified global variable.
                   1537: Only global variables may be un-defined.
1.165     sjg      1538: .It Ic .unexport Ar variable ...
                   1539: The opposite of
                   1540: .Ql .export .
                   1541: The specified global
1.166     wiz      1542: .Va variable
                   1543: will be removed from
1.165     sjg      1544: .Va .MAKE.EXPORTED .
                   1545: If no variable list is provided, all globals are unexported,
                   1546: and
1.166     wiz      1547: .Va .MAKE.EXPORTED
1.165     sjg      1548: deleted.
                   1549: .It Ic .unexport-env
                   1550: Unexport all globals previously exported and
                   1551: clear the environment inherited from the parent.
1.166     wiz      1552: This operation will cause a memory leak of the original environment,
                   1553: so should be used sparingly.
                   1554: Testing for
1.165     sjg      1555: .Va .MAKE.LEVEL
                   1556: being 0, would make sense.
1.166     wiz      1557: Also note that any variables which originated in the parent environment
1.165     sjg      1558: should be explicitly preserved if desired.
                   1559: For example:
                   1560: .Bd -literal -offset indent
                   1561: .Li .if ${.MAKE.LEVEL} == 0
                   1562: PATH := ${PATH}
                   1563: .Li .unexport-env
                   1564: .Li .export PATH
                   1565: .Li .endif
                   1566: .Pp
                   1567: .Ed
1.166     wiz      1568: Would result in an environment containing only
1.165     sjg      1569: .Ql Ev PATH ,
                   1570: which is the minimal useful environment.
                   1571: Actually
1.166     wiz      1572: .Ql Ev .MAKE.LEVEL
1.165     sjg      1573: will also be pushed into the new environment.
1.168     sjg      1574: .It Ic .warning Ar message
                   1575: The message prefixed by
                   1576: .Ql Pa warning:
                   1577: is printed along with the name of the makefile and line number.
1.164     joerg    1578: .It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ...
1.1       cgd      1579: Test the value of an expression.
1.164     joerg    1580: .It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1.7       mycroft  1581: Test the value of a variable.
1.164     joerg    1582: .It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1.7       mycroft  1583: Test the value of a variable.
1.164     joerg    1584: .It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1.7       mycroft  1585: Test the target being built.
1.164     joerg    1586: .It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ...
1.1       cgd      1587: Test the target being built.
                   1588: .It Ic .else
                   1589: Reverse the sense of the last conditional.
1.164     joerg    1590: .It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ...
1.1       cgd      1591: A combination of
                   1592: .Ql Ic .else
                   1593: followed by
                   1594: .Ql Ic .if .
1.164     joerg    1595: .It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1.1       cgd      1596: A combination of
                   1597: .Ql Ic .else
                   1598: followed by
                   1599: .Ql Ic .ifdef .
1.164     joerg    1600: .It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1.1       cgd      1601: A combination of
                   1602: .Ql Ic .else
                   1603: followed by
                   1604: .Ql Ic .ifndef .
1.164     joerg    1605: .It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1.1       cgd      1606: A combination of
                   1607: .Ql Ic .else
                   1608: followed by
                   1609: .Ql Ic .ifmake .
1.164     joerg    1610: .It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1.1       cgd      1611: A combination of
                   1612: .Ql Ic .else
                   1613: followed by
                   1614: .Ql Ic .ifnmake .
                   1615: .It Ic .endif
                   1616: End the body of the conditional.
                   1617: .El
                   1618: .Pp
                   1619: The
                   1620: .Ar operator
                   1621: may be any one of the following:
                   1622: .Bl -tag -width "Cm XX"
                   1623: .It Cm \&|\&|
1.64      wiz      1624: Logical OR.
1.62      ross     1625: .It Cm \&\*[Am]\*[Am]
1.1       cgd      1626: Logical
                   1627: .Tn AND ;
                   1628: of higher precedence than
1.26      hubertf  1629: .Dq \&|\&| .
1.1       cgd      1630: .El
                   1631: .Pp
                   1632: As in C,
1.25      lukem    1633: .Nm
1.1       cgd      1634: will only evaluate a conditional as far as is necessary to determine
                   1635: its value.
1.16      christos 1636: Parentheses may be used to change the order of evaluation.
1.1       cgd      1637: The boolean operator
                   1638: .Ql Ic \&!
                   1639: may be used to logically negate an entire
                   1640: conditional.
1.5       jtc      1641: It is of higher precedence than
1.62      ross     1642: .Ql Ic \&\*[Am]\*[Am] .
1.1       cgd      1643: .Pp
                   1644: The value of
                   1645: .Ar expression
                   1646: may be any of the following:
1.61      ross     1647: .Bl -tag -width defined
1.1       cgd      1648: .It Ic defined
                   1649: Takes a variable name as an argument and evaluates to true if the variable
                   1650: has been defined.
                   1651: .It Ic make
                   1652: Takes a target name as an argument and evaluates to true if the target
                   1653: was specified as part of
1.74      wiz      1654: .Nm Ns 's
1.1       cgd      1655: command line or was declared the default target (either implicitly or
                   1656: explicitly, see
                   1657: .Va .MAIN )
                   1658: before the line containing the conditional.
                   1659: .It Ic empty
1.5       jtc      1660: Takes a variable, with possible modifiers, and evaluates to true if
1.1       cgd      1661: the expansion of the variable would result in an empty string.
                   1662: .It Ic exists
                   1663: Takes a file name as an argument and evaluates to true if the file exists.
                   1664: The file is searched for on the system search path (see
                   1665: .Va .PATH ) .
                   1666: .It Ic target
                   1667: Takes a target name as an argument and evaluates to true if the target
                   1668: has been defined.
1.47      christos 1669: .It Ic commands
                   1670: Takes a target name as an argument and evaluates to true if the target
                   1671: has been defined and has commands associated with it.
1.1       cgd      1672: .El
                   1673: .Pp
                   1674: .Ar Expression
1.67      grant    1675: may also be an arithmetic or string comparison.
                   1676: Variable expansion is
1.6       cgd      1677: performed on both sides of the comparison, after which the integral
1.67      grant    1678: values are compared.
                   1679: A value is interpreted as hexadecimal if it is
1.6       cgd      1680: preceded by 0x, otherwise it is decimal; octal numbers are not supported.
1.67      grant    1681: The standard C relational operators are all supported.
                   1682: If after
1.6       cgd      1683: variable expansion, either the left or right hand side of a
1.1       cgd      1684: .Ql Ic ==
                   1685: or
                   1686: .Ql Ic "!="
1.6       cgd      1687: operator is not an integral value, then
                   1688: string comparison is performed between the expanded
                   1689: variables.
1.1       cgd      1690: If no relational operator is given, it is assumed that the expanded
1.102     sjg      1691: variable is being compared against 0 or an empty string in the case
                   1692: of a string comparison.
1.1       cgd      1693: .Pp
                   1694: When
1.25      lukem    1695: .Nm
1.150     dsl      1696: is evaluating one of these conditional expressions, and it encounters
                   1697: a (white-space separated) word it doesn't recognize, either the
1.137     wiz      1698: .Dq make
                   1699: or
                   1700: .Dq defined
1.1       cgd      1701: expression is applied to it, depending on the form of the conditional.
                   1702: If the form is
1.150     dsl      1703: .Ql Ic .ifdef ,
                   1704: .Ql Ic .ifndef ,
1.1       cgd      1705: or
1.150     dsl      1706: .Ql Ic .if
1.137     wiz      1707: the
                   1708: .Dq defined
                   1709: expression is applied.
1.1       cgd      1710: Similarly, if the form is
                   1711: .Ql Ic .ifmake
                   1712: or
1.237     dholland 1713: .Ql Ic .ifnmake , the
1.137     wiz      1714: .Dq make
1.1       cgd      1715: expression is applied.
                   1716: .Pp
                   1717: If the conditional evaluates to true the parsing of the makefile continues
                   1718: as before.
                   1719: If it evaluates to false, the following lines are skipped.
                   1720: In both cases this continues until a
                   1721: .Ql Ic .else
                   1722: or
                   1723: .Ql Ic .endif
                   1724: is found.
1.16      christos 1725: .Pp
1.6       cgd      1726: For loops are typically used to apply a set of rules to a list of files.
                   1727: The syntax of a for loop is:
1.59      bgrayson 1728: .Pp
                   1729: .Bl -tag -compact -width Ds
1.164     joerg    1730: .It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression
1.80      wiz      1731: .It Aq make-rules
                   1732: .It Ic \&.endfor
1.6       cgd      1733: .El
1.59      bgrayson 1734: .Pp
1.6       cgd      1735: After the for
1.16      christos 1736: .Ic expression
1.67      grant    1737: is evaluated, it is split into words.
                   1738: On each iteration of the loop, one word is taken and assigned to each
1.39      christos 1739: .Ic variable ,
                   1740: in order, and these
                   1741: .Ic variables
                   1742: are substituted into the
1.16      christos 1743: .Ic make-rules
1.6       cgd      1744: inside the body of the for loop.
1.39      christos 1745: The number of words must come out even; that is, if there are three
                   1746: iteration variables, the number of words provided must be a multiple
                   1747: of three.
1.1       cgd      1748: .Sh COMMENTS
                   1749: Comments begin with a hash
                   1750: .Pq Ql \&#
                   1751: character, anywhere but in a shell
1.237     dholland 1752: command line, and continue to the end of an unescaped new line.
1.97      lukem    1753: .Sh SPECIAL SOURCES (ATTRIBUTES)
1.61      ross     1754: .Bl -tag -width .IGNOREx
1.97      lukem    1755: .It Ic .EXEC
                   1756: Target is never out of date, but always execute commands anyway.
1.1       cgd      1757: .It Ic .IGNORE
                   1758: Ignore any errors from the commands associated with this target, exactly
                   1759: as if they all were preceded by a dash
                   1760: .Pq Ql \- .
1.237     dholland 1761: .\" .It Ic .INVISIBLE
                   1762: .\" XXX
                   1763: .\" .It Ic .JOIN
                   1764: .\" XXX
1.18      christos 1765: .It Ic .MADE
1.48      wiz      1766: Mark all sources of this target as being up-to-date.
1.1       cgd      1767: .It Ic .MAKE
                   1768: Execute the commands associated with this target even if the
                   1769: .Fl n
                   1770: or
                   1771: .Fl t
                   1772: options were specified.
                   1773: Normally used to mark recursive
1.226     dholland 1774: .Nm Ns s .
1.180     sjg      1775: .It Ic .META
                   1776: Create a meta file for the target, even if it is flagged as
                   1777: .Ic .PHONY ,
1.182     wiz      1778: .Ic .MAKE ,
1.180     sjg      1779: or
                   1780: .Ic .SPECIAL .
                   1781: Usage in conjunction with
                   1782: .Ic .MAKE
                   1783: is the most likely case.
1.194     sjg      1784: In "meta" mode, the target is out-of-date if the meta file is missing.
1.180     sjg      1785: .It Ic .NOMETA
                   1786: Do not create a meta file for the target.
                   1787: Meta files are also not created for
                   1788: .Ic .PHONY ,
1.182     wiz      1789: .Ic .MAKE ,
1.180     sjg      1790: or
                   1791: .Ic .SPECIAL
                   1792: targets.
                   1793: .It Ic .NOMETA_CMP
                   1794: Ignore differences in commands when deciding if target is out of date.
                   1795: This is useful if the command contains a value which always changes.
1.182     wiz      1796: If the number of commands change, though, the target will still be out of date.
1.213     sjg      1797: The same effect applies to any command line that uses the variable
                   1798: .Va .OODATE ,
                   1799: which can be used for that purpose even when not otherwise needed or desired:
                   1800: .Bd -literal -offset indent
                   1801:
                   1802: skip-compare-for-some:
                   1803:        @echo this will be compared
                   1804:        @echo this will not ${.OODATE:M.NOMETA_CMP}
                   1805:        @echo this will also be compared
                   1806:
                   1807: .Ed
                   1808: The
                   1809: .Cm \&:M
                   1810: pattern suppresses any expansion of the unwanted variable.
1.97      lukem    1811: .It Ic .NOPATH
                   1812: Do not search for the target in the directories specified by
                   1813: .Ic .PATH .
1.1       cgd      1814: .It Ic .NOTMAIN
                   1815: Normally
1.25      lukem    1816: .Nm
1.1       cgd      1817: selects the first target it encounters as the default target to be built
                   1818: if no target was specified.
                   1819: This source prevents this target from being selected.
                   1820: .It Ic .OPTIONAL
                   1821: If a target is marked with this attribute and
1.25      lukem    1822: .Nm
1.1       cgd      1823: can't figure out how to create it, it will ignore this fact and assume
                   1824: the file isn't needed or already exists.
1.97      lukem    1825: .It Ic .PHONY
                   1826: The target does not
                   1827: correspond to an actual file; it is always considered to be out of date,
                   1828: and will not be created with the
                   1829: .Fl t
                   1830: option.
1.179     dholland 1831: Suffix-transformation rules are not applied to
                   1832: .Ic .PHONY
                   1833: targets.
1.1       cgd      1834: .It Ic .PRECIOUS
                   1835: When
1.25      lukem    1836: .Nm
1.131     rillig   1837: is interrupted, it normally removes any partially made targets.
1.1       cgd      1838: This source prevents the target from being removed.
1.97      lukem    1839: .It Ic .RECURSIVE
                   1840: Synonym for
                   1841: .Ic .MAKE .
1.1       cgd      1842: .It Ic .SILENT
                   1843: Do not echo any of the commands associated with this target, exactly
                   1844: as if they all were preceded by an at sign
                   1845: .Pq Ql @ .
                   1846: .It Ic .USE
                   1847: Turn the target into
1.74      wiz      1848: .Nm Ns 's
1.1       cgd      1849: version of a macro.
                   1850: When the target is used as a source for another target, the other target
                   1851: acquires the commands, sources, and attributes (except for
                   1852: .Ic .USE )
                   1853: of the
                   1854: source.
                   1855: If the target already has commands, the
                   1856: .Ic .USE
                   1857: target's commands are appended
                   1858: to them.
1.52      christos 1859: .It Ic .USEBEFORE
                   1860: Exactly like
                   1861: .Ic .USE ,
1.57      wiz      1862: but prepend the
1.52      christos 1863: .Ic .USEBEFORE
                   1864: target commands to the target.
1.12      christos 1865: .It Ic .WAIT
1.71      mjl      1866: If
1.12      christos 1867: .Ic .WAIT
1.71      mjl      1868: appears in a dependency line, the sources that precede it are
1.67      grant    1869: made before the sources that succeed it in the line.
1.128     dsl      1870: Since the dependents of files are not made until the file itself
                   1871: could be made, this also stops the dependents being built unless they
                   1872: are needed for another branch of the dependency tree.
                   1873: So given:
                   1874: .Bd -literal
                   1875: x: a .WAIT b
                   1876:        echo x
                   1877: a:
                   1878:        echo a
                   1879: b: b1
                   1880:        echo b
                   1881: b1:
                   1882:        echo b1
                   1883:
                   1884: .Ed
                   1885: the output is always
1.151     dholland 1886: .Ql a ,
1.128     dsl      1887: .Ql b1 ,
                   1888: .Ql b ,
                   1889: .Ql x .
                   1890: .br
1.122     apb      1891: The ordering imposed by
                   1892: .Ic .WAIT
1.128     dsl      1893: is only relevant for parallel makes.
1.1       cgd      1894: .El
1.57      wiz      1895: .Sh SPECIAL TARGETS
1.1       cgd      1896: Special targets may not be included with other targets, i.e. they must be
                   1897: the only target specified.
1.61      ross     1898: .Bl -tag -width .BEGINx
1.1       cgd      1899: .It Ic .BEGIN
                   1900: Any command lines attached to this target are executed before anything
                   1901: else is done.
                   1902: .It Ic .DEFAULT
                   1903: This is sort of a
                   1904: .Ic .USE
                   1905: rule for any target (that was used only as a
                   1906: source) that
1.25      lukem    1907: .Nm
1.1       cgd      1908: can't figure out any other way to create.
                   1909: Only the shell script is used.
                   1910: The
                   1911: .Ic .IMPSRC
                   1912: variable of a target that inherits
                   1913: .Ic .DEFAULT Ns 's
                   1914: commands is set
                   1915: to the target's own name.
                   1916: .It Ic .END
                   1917: Any command lines attached to this target are executed after everything
                   1918: else is done.
1.168     sjg      1919: .It Ic .ERROR
                   1920: Any command lines attached to this target are executed when another target fails.
                   1921: The
                   1922: .Ic .ERROR_TARGET
                   1923: variable is set to the target that failed.
1.169     wiz      1924: See also
1.168     sjg      1925: .Ic MAKE_PRINT_VAR_ON_ERROR .
1.1       cgd      1926: .It Ic .IGNORE
                   1927: Mark each of the sources with the
                   1928: .Ic .IGNORE
                   1929: attribute.
                   1930: If no sources are specified, this is the equivalent of specifying the
                   1931: .Fl i
                   1932: option.
                   1933: .It Ic .INTERRUPT
                   1934: If
1.25      lukem    1935: .Nm
1.1       cgd      1936: is interrupted, the commands for this target will be executed.
                   1937: .It Ic .MAIN
                   1938: If no target is specified when
1.25      lukem    1939: .Nm
1.1       cgd      1940: is invoked, this target will be built.
                   1941: .It Ic .MAKEFLAGS
                   1942: This target provides a way to specify flags for
1.25      lukem    1943: .Nm
1.1       cgd      1944: when the makefile is used.
                   1945: The flags are as if typed to the shell, though the
                   1946: .Fl f
                   1947: option will have
                   1948: no effect.
1.12      christos 1949: .\" XXX: NOT YET!!!!
                   1950: .\" .It Ic .NOTPARALLEL
1.70      wiz      1951: .\" The named targets are executed in non parallel mode.
                   1952: .\" If no targets are
1.12      christos 1953: .\" specified, then all targets are executed in non parallel mode.
1.20      gwr      1954: .It Ic .NOPATH
                   1955: Apply the
                   1956: .Ic .NOPATH
1.67      grant    1957: attribute to any specified sources.
1.12      christos 1958: .It Ic .NOTPARALLEL
                   1959: Disable parallel mode.
                   1960: .It Ic .NO_PARALLEL
1.97      lukem    1961: Synonym for
                   1962: .Ic .NOTPARALLEL ,
                   1963: for compatibility with other pmake variants.
1.12      christos 1964: .It Ic .ORDER
                   1965: The named targets are made in sequence.
1.128     dsl      1966: This ordering does not add targets to the list of targets to be made.
                   1967: Since the dependents of a target do not get built until the target itself
                   1968: could be built, unless
                   1969: .Ql a
1.129     wiz      1970: is built by another part of the dependency graph,
1.128     dsl      1971: the following is a dependency loop:
                   1972: .Bd -literal
1.192     cheusov  1973: \&.ORDER: b a
1.128     dsl      1974: b: a
                   1975: .Ed
1.129     wiz      1976: .Pp
1.122     apb      1977: The ordering imposed by
                   1978: .Ic .ORDER
1.128     dsl      1979: is only relevant for parallel makes.
1.12      christos 1980: .\" XXX: NOT YET!!!!
                   1981: .\" .It Ic .PARALLEL
1.70      wiz      1982: .\" The named targets are executed in parallel mode.
                   1983: .\" If no targets are
1.12      christos 1984: .\" specified, then all targets are executed in parallel mode.
1.1       cgd      1985: .It Ic .PATH
                   1986: The sources are directories which are to be searched for files not
                   1987: found in the current directory.
                   1988: If no sources are specified, any previously specified directories are
                   1989: deleted.
1.34      thorpej  1990: If the source is the special
                   1991: .Ic .DOTLAST
                   1992: target, then the current working
1.33      thorpej  1993: directory is searched last.
1.222     apb      1994: .It Ic .PATH. Ns Va suffix
1.221     dholland 1995: Like
                   1996: .Ic .PATH
                   1997: but applies only to files with a particular suffix.
                   1998: The suffix must have been previously declared with
                   1999: .Ic .SUFFIXES .
1.14      christos 2000: .It Ic .PHONY
                   2001: Apply the
                   2002: .Ic .PHONY
1.67      grant    2003: attribute to any specified sources.
1.1       cgd      2004: .It Ic .PRECIOUS
                   2005: Apply the
                   2006: .Ic .PRECIOUS
                   2007: attribute to any specified sources.
                   2008: If no sources are specified, the
                   2009: .Ic .PRECIOUS
                   2010: attribute is applied to every
                   2011: target in the file.
1.83      sjg      2012: .It Ic .SHELL
1.86      wiz      2013: Sets the shell that
1.83      sjg      2014: .Nm
1.86      wiz      2015: will use to execute commands.
                   2016: The sources are a set of
1.83      sjg      2017: .Ar field=value
1.86      wiz      2018: pairs.
1.83      sjg      2019: .Bl -tag -width hasErrCtls
                   2020: .It Ar name
                   2021: This is the minimal specification, used to select one of the builtin
                   2022: shell specs;
                   2023: .Ar sh ,
                   2024: .Ar ksh ,
                   2025: and
                   2026: .Ar csh .
                   2027: .It Ar path
                   2028: Specifies the path to the shell.
                   2029: .It Ar hasErrCtl
                   2030: Indicates whether the shell supports exit on error.
                   2031: .It Ar check
                   2032: The command to turn on error checking.
                   2033: .It Ar ignore
                   2034: The command to disable error checking.
                   2035: .It Ar echo
                   2036: The command to turn on echoing of commands executed.
                   2037: .It Ar quiet
                   2038: The command to turn off echoing of commands executed.
                   2039: .It Ar filter
                   2040: The output to filter after issuing the
                   2041: .Ar quiet
1.86      wiz      2042: command.
                   2043: It is typically identical to
1.83      sjg      2044: .Ar quiet .
                   2045: .It Ar errFlag
                   2046: The flag to pass the shell to enable error checking.
                   2047: .It Ar echoFlag
                   2048: The flag to pass the shell to enable command echoing.
1.127     rillig   2049: .It Ar newline
                   2050: The string literal to pass the shell that results in a single newline
                   2051: character when used outside of any quoting characters.
1.83      sjg      2052: .El
                   2053: Example:
                   2054: .Bd -literal
1.167     joerg    2055: \&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e
1.194     sjg      2056:        check="set \-e" ignore="set +e" \e
                   2057:        echo="set \-v" quiet="set +v" filter="set +v" \e
1.167     joerg    2058:        echoFlag=v errFlag=e newline="'\en'"
1.83      sjg      2059: .Ed
1.1       cgd      2060: .It Ic .SILENT
                   2061: Apply the
                   2062: .Ic .SILENT
                   2063: attribute to any specified sources.
                   2064: If no sources are specified, the
                   2065: .Ic .SILENT
                   2066: attribute is applied to every
                   2067: command in the file.
1.211     christos 2068: .It Ic .STALE
                   2069: This target gets run when a dependency file contains stale entries, having
                   2070: .Va .ALLSRC
                   2071: set to the name of that dependency file.
1.1       cgd      2072: .It Ic .SUFFIXES
1.237     dholland 2073: Each source specifies a suffix to
1.233     christos 2074: .Nm .
1.237     dholland 2075: If no sources are specified, any previously specified suffixes are deleted.
                   2076: It allows the creation of suffix-transformation rules.
1.136     cube     2077: .Pp
                   2078: Example:
                   2079: .Bd -literal
1.237     dholland 2080: \&.SUFFIXES: .o
                   2081: \&.c.o:
1.194     sjg      2082:        cc \-o ${.TARGET} \-c ${.IMPSRC}
1.136     cube     2083: .Ed
1.31      ross     2084: .El
1.1       cgd      2085: .Sh ENVIRONMENT
1.25      lukem    2086: .Nm
1.73      perry    2087: uses the following environment variables, if they exist:
1.16      christos 2088: .Ev MACHINE ,
1.26      hubertf  2089: .Ev MACHINE_ARCH ,
1.1       cgd      2090: .Ev MAKE ,
1.16      christos 2091: .Ev MAKEFLAGS ,
                   2092: .Ev MAKEOBJDIR ,
1.38      sjg      2093: .Ev MAKEOBJDIRPREFIX ,
1.76      jrf      2094: .Ev MAKESYSPATH ,
1.154     apb      2095: .Ev PWD ,
1.1       cgd      2096: and
1.154     apb      2097: .Ev TMPDIR .
1.57      wiz      2098: .Pp
1.38      sjg      2099: .Ev MAKEOBJDIRPREFIX
1.117     lukem    2100: and
1.38      sjg      2101: .Ev MAKEOBJDIR
1.117     lukem    2102: may only be set in the environment or on the command line to
1.38      sjg      2103: .Nm
1.117     lukem    2104: and not as makefile variables;
                   2105: see the description of
                   2106: .Ql Va .OBJDIR
                   2107: for more details.
1.1       cgd      2108: .Sh FILES
                   2109: .Bl -tag -width /usr/share/mk -compact
                   2110: .It .depend
                   2111: list of dependencies
                   2112: .It Makefile
                   2113: list of dependencies
                   2114: .It makefile
                   2115: list of dependencies
                   2116: .It sys.mk
                   2117: system makefile
                   2118: .It /usr/share/mk
                   2119: system makefile directory
                   2120: .El
1.128     dsl      2121: .Sh COMPATIBILITY
                   2122: The basic make syntax is compatible between different versions of make,
                   2123: however the special variables, variable modifiers and conditionals are not.
                   2124: .Pp
1.129     wiz      2125: The way that parallel makes are scheduled changed in
1.130     wiz      2126: .Nx 4.0
1.193     wiz      2127: so that .ORDER and .WAIT apply recursively to the dependent nodes.
1.128     dsl      2128: The algorithms used may change again in the future.
1.152     dsl      2129: .Pp
                   2130: The way that .for loop variables are substituted changed after
                   2131: .Nx 5.0
                   2132: so that they still appear to be variable expansions.
                   2133: In particular this stops them being treated as syntax, and removes some
                   2134: obscure problems using them in .if statements.
1.153     wiz      2135: .Sh SEE ALSO
                   2136: .Xr mkdep 1
                   2137: .Sh HISTORY
                   2138: A
                   2139: .Nm
                   2140: command appeared in
                   2141: .At v7 .
1.190     christos 2142: This
                   2143: .Nm
                   2144: implementation is based on Adam De Boor's pmake program which was written
1.209     christos 2145: for Sprite at Berkeley.
1.190     christos 2146: It was designed to be a parallel distributed make running jobs on different
1.191     wiz      2147: machines using a daemon called
1.190     christos 2148: .Dq customs .
1.237     dholland 2149: .Pp
                   2150: Historically the target/dependency
                   2151: .Dq FRC
                   2152: has been used to FoRCe rebuilding (since the target/dependency
                   2153: does not exist... unless someone creates an
                   2154: .Dq FRC
                   2155: file).
1.152     dsl      2156: .Sh BUGS
                   2157: The
                   2158: .Nm
                   2159: syntax is difficult to parse without actually acting of the data.
                   2160: For instance finding the end of a variable use should involve scanning each
                   2161: the modifiers using the correct terminator for each field.
                   2162: In many places
                   2163: .Nm
                   2164: just counts {} and () in order to find the end of a variable expansion.
                   2165: .Pp
1.153     wiz      2166: There is no way of escaping a space character in a filename.

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