1.\" $NetBSD: make.1,v 1.255 2016/03/14 07:42:15 matthias Exp $ 2.\" 3.\" Copyright (c) 1990, 1993 4.\" The Regents of the University of California. All rights reserved. 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. 14.\" 3. Neither the name of the University nor the names of its contributors 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. 29.\" 30.\" from: @(#)make.1 8.4 (Berkeley) 3/19/94 31.\" 32.Dd February 19, 2016 33.Dt MAKE 1 34.Os 35.Sh NAME 36.Nm make 37.Nd maintain program dependencies 38.Sh SYNOPSIS 39.Nm 40.Op Fl BeikNnqrstWwX 41.Op Fl C Ar directory 42.Op Fl D Ar variable 43.Op Fl d Ar flags 44.Op Fl f Ar makefile 45.Op Fl I Ar directory 46.Op Fl J Ar private 47.Op Fl j Ar max_jobs 48.Op Fl m Ar directory 49.Op Fl T Ar file 50.Op Fl V Ar variable 51.Op Ar variable=value 52.Op Ar target ... 53.Sh DESCRIPTION 54.Nm 55is a program designed to simplify the maintenance of other programs. 56Its input is a list of specifications as to the files upon which programs 57and other files depend. 58If no 59.Fl f Ar makefile 60makefile option is given, 61.Nm 62will try to open 63.Ql Pa makefile 64then 65.Ql Pa Makefile 66in order to find the specifications. 67If the file 68.Ql Pa .depend 69exists, it is read (see 70.Xr mkdep 1 ) . 71.Pp 72This manual page is intended as a reference document only. 73For a more thorough description of 74.Nm 75and makefiles, please refer to 76.%T "PMake \- A Tutorial" . 77.Pp 78.Nm 79will prepend the contents of the 80.Va MAKEFLAGS 81environment variable to the command line arguments before parsing them. 82.Pp 83The options are as follows: 84.Bl -tag -width Ds 85.It Fl B 86Try to be backwards compatible by executing a single shell per command and 87by executing the commands to make the sources of a dependency line in sequence. 88.It Fl C Ar directory 89Change to 90.Ar directory 91before reading the makefiles or doing anything else. 92If multiple 93.Fl C 94options are specified, each is interpreted relative to the previous one: 95.Fl C Pa / Fl C Pa etc 96is equivalent to 97.Fl C Pa /etc . 98.It Fl D Ar variable 99Define 100.Ar variable 101to be 1, in the global context. 102.It Fl d Ar [-]flags 103Turn on debugging, and specify which portions of 104.Nm 105are to print debugging information. 106Unless the flags are preceded by 107.Ql \- 108they are added to the 109.Va MAKEFLAGS 110environment variable and will be processed by any child make processes. 111By default, debugging information is printed to standard error, 112but this can be changed using the 113.Ar F 114debugging flag. 115The debugging output is always unbuffered; in addition, if debugging 116is enabled but debugging output is not directed to standard output, 117then the standard output is line buffered. 118.Ar Flags 119is one or more of the following: 120.Bl -tag -width Ds 121.It Ar A 122Print all possible debugging information; 123equivalent to specifying all of the debugging flags. 124.It Ar a 125Print debugging information about archive searching and caching. 126.It Ar C 127Print debugging information about current working directory. 128.It Ar c 129Print debugging information about conditional evaluation. 130.It Ar d 131Print debugging information about directory searching and caching. 132.It Ar e 133Print debugging information about failed commands and targets. 134.It Ar F Ns Oo Sy \&+ Oc Ns Ar filename 135Specify where debugging output is written. 136This must be the last flag, because it consumes the remainder of 137the argument. 138If the character immediately after the 139.Ql F 140flag is 141.Ql \&+ , 142then the file will be opened in append mode; 143otherwise the file will be overwritten. 144If the file name is 145.Ql stdout 146or 147.Ql stderr 148then debugging output will be written to the 149standard output or standard error output file descriptors respectively 150(and the 151.Ql \&+ 152option has no effect). 153Otherwise, the output will be written to the named file. 154If the file name ends 155.Ql .%d 156then the 157.Ql %d 158is replaced by the pid. 159.It Ar f 160Print debugging information about loop evaluation. 161.It Ar "g1" 162Print the input graph before making anything. 163.It Ar "g2" 164Print the input graph after making everything, or before exiting 165on error. 166.It Ar "g3" 167Print the input graph before exiting on error. 168.It Ar j 169Print debugging information about running multiple shells. 170.It Ar l 171Print commands in Makefiles regardless of whether or not they are prefixed by 172.Ql @ 173or other "quiet" flags. 174Also known as "loud" behavior. 175.It Ar M 176Print debugging information about "meta" mode decisions about targets. 177.It Ar m 178Print debugging information about making targets, including modification 179dates. 180.It Ar n 181Don't delete the temporary command scripts created when running commands. 182These temporary scripts are created in the directory 183referred to by the 184.Ev TMPDIR 185environment variable, or in 186.Pa /tmp 187if 188.Ev TMPDIR 189is unset or set to the empty string. 190The temporary scripts are created by 191.Xr mkstemp 3 , 192and have names of the form 193.Pa makeXXXXXX . 194.Em NOTE : 195This can create many files in 196.Ev TMPDIR 197or 198.Pa /tmp , 199so use with care. 200.It Ar p 201Print debugging information about makefile parsing. 202.It Ar s 203Print debugging information about suffix-transformation rules. 204.It Ar t 205Print debugging information about target list maintenance. 206.It Ar V 207Force the 208.Fl V 209option to print raw values of variables. 210.It Ar v 211Print debugging information about variable assignment. 212.It Ar x 213Run shell commands with 214.Fl x 215so the actual commands are printed as they are executed. 216.El 217.It Fl e 218Specify that environment variables override macro assignments within 219makefiles. 220.It Fl f Ar makefile 221Specify a makefile to read instead of the default 222.Ql Pa makefile . 223If 224.Ar makefile 225is 226.Ql Fl , 227standard input is read. 228Multiple makefiles may be specified, and are read in the order specified. 229.It Fl I Ar directory 230Specify a directory in which to search for makefiles and included makefiles. 231The system makefile directory (or directories, see the 232.Fl m 233option) is automatically included as part of this list. 234.It Fl i 235Ignore non-zero exit of shell commands in the makefile. 236Equivalent to specifying 237.Ql Fl 238before each command line in the makefile. 239.It Fl J Ar private 240This option should 241.Em not 242be specified by the user. 243.Pp 244When the 245.Ar j 246option is in use in a recursive build, this option is passed by a make 247to child makes to allow all the make processes in the build to 248cooperate to avoid overloading the system. 249.It Fl j Ar max_jobs 250Specify the maximum number of jobs that 251.Nm 252may have running at any one time. 253The value is saved in 254.Va .MAKE.JOBS . 255Turns compatibility mode off, unless the 256.Ar B 257flag is also specified. 258When compatibility mode is off, all commands associated with a 259target are executed in a single shell invocation as opposed to the 260traditional one shell invocation per line. 261This can break traditional scripts which change directories on each 262command invocation and then expect to start with a fresh environment 263on the next line. 264It is more efficient to correct the scripts rather than turn backwards 265compatibility on. 266.It Fl k 267Continue processing after errors are encountered, but only on those targets 268that do not depend on the target whose creation caused the error. 269.It Fl m Ar directory 270Specify a directory in which to search for sys.mk and makefiles included 271via the 272.Ao Ar file Ac Ns -style 273include statement. 274The 275.Fl m 276option can be used multiple times to form a search path. 277This path will override the default system include path: /usr/share/mk. 278Furthermore the system include path will be appended to the search path used 279for 280.Qo Ar file Qc Ns -style 281include statements (see the 282.Fl I 283option). 284.Pp 285If a file or directory name in the 286.Fl m 287argument (or the 288.Ev MAKESYSPATH 289environment variable) starts with the string 290.Qq \&.../ 291then 292.Nm 293will search for the specified file or directory named in the remaining part 294of the argument string. 295The search starts with the current directory of 296the Makefile and then works upward towards the root of the file system. 297If the search is successful, then the resulting directory replaces the 298.Qq \&.../ 299specification in the 300.Fl m 301argument. 302If used, this feature allows 303.Nm 304to easily search in the current source tree for customized sys.mk files 305(e.g., by using 306.Qq \&.../mk/sys.mk 307as an argument). 308.It Fl n 309Display the commands that would have been executed, but do not 310actually execute them unless the target depends on the .MAKE special 311source (see below). 312.It Fl N 313Display the commands which would have been executed, but do not 314actually execute any of them; useful for debugging top-level makefiles 315without descending into subdirectories. 316.It Fl q 317Do not execute any commands, but exit 0 if the specified targets are 318up-to-date and 1, otherwise. 319.It Fl r 320Do not use the built-in rules specified in the system makefile. 321.It Fl s 322Do not echo any commands as they are executed. 323Equivalent to specifying 324.Ql Ic @ 325before each command line in the makefile. 326.It Fl T Ar tracefile 327When used with the 328.Fl j 329flag, 330append a trace record to 331.Ar tracefile 332for each job started and completed. 333.It Fl t 334Rather than re-building a target as specified in the makefile, create it 335or update its modification time to make it appear up-to-date. 336.It Fl V Ar variable 337Print 338.Nm Ns 's 339idea of the value of 340.Ar variable , 341in the global context. 342Do not build any targets. 343Multiple instances of this option may be specified; 344the variables will be printed one per line, 345with a blank line for each null or undefined variable. 346If 347.Ar variable 348contains a 349.Ql \&$ 350then the value will be expanded before printing. 351.It Fl W 352Treat any warnings during makefile parsing as errors. 353.It Fl w 354Print entering and leaving directory messages, pre and post processing. 355.It Fl X 356Don't export variables passed on the command line to the environment 357individually. 358Variables passed on the command line are still exported 359via the 360.Va MAKEFLAGS 361environment variable. 362This option may be useful on systems which have a small limit on the 363size of command arguments. 364.It Ar variable=value 365Set the value of the variable 366.Ar variable 367to 368.Ar value . 369Normally, all values passed on the command line are also exported to 370sub-makes in the environment. 371The 372.Fl X 373flag disables this behavior. 374Variable assignments should follow options for POSIX compatibility 375but no ordering is enforced. 376.El 377.Pp 378There are seven different types of lines in a makefile: file dependency 379specifications, shell commands, variable assignments, include statements, 380conditional directives, for loops, and comments. 381.Pp 382In general, lines may be continued from one line to the next by ending 383them with a backslash 384.Pq Ql \e . 385The trailing newline character and initial whitespace on the following 386line are compressed into a single space. 387.Sh FILE DEPENDENCY SPECIFICATIONS 388Dependency lines consist of one or more targets, an operator, and zero 389or more sources. 390This creates a relationship where the targets 391.Dq depend 392on the sources 393and are usually created from them. 394The exact relationship between the target and the source is determined 395by the operator that separates them. 396The three operators are as follows: 397.Bl -tag -width flag 398.It Ic \&: 399A target is considered out-of-date if its modification time is less than 400those of any of its sources. 401Sources for a target accumulate over dependency lines when this operator 402is used. 403The target is removed if 404.Nm 405is interrupted. 406.It Ic \&! 407Targets are always re-created, but not until all sources have been 408examined and re-created as necessary. 409Sources for a target accumulate over dependency lines when this operator 410is used. 411The target is removed if 412.Nm 413is interrupted. 414.It Ic \&:: 415If no sources are specified, the target is always re-created. 416Otherwise, a target is considered out-of-date if any of its sources has 417been modified more recently than the target. 418Sources for a target do not accumulate over dependency lines when this 419operator is used. 420The target will not be removed if 421.Nm 422is interrupted. 423.El 424.Pp 425Targets and sources may contain the shell wildcard values 426.Ql \&? , 427.Ql * , 428.Ql [] , 429and 430.Ql {} . 431The values 432.Ql \&? , 433.Ql * , 434and 435.Ql [] 436may only be used as part of the final 437component of the target or source, and must be used to describe existing 438files. 439The value 440.Ql {} 441need not necessarily be used to describe existing files. 442Expansion is in directory order, not alphabetically as done in the shell. 443.Sh SHELL COMMANDS 444Each target may have associated with it one or more lines of shell 445commands, normally 446used to create the target. 447Each of the lines in this script 448.Em must 449be preceded by a tab. 450(For historical reasons, spaces are not accepted.) 451While targets can appear in many dependency lines if desired, by 452default only one of these rules may be followed by a creation 453script. 454If the 455.Ql Ic \&:: 456operator is used, however, all rules may include scripts and the 457scripts are executed in the order found. 458.Pp 459Each line is treated as a separate shell command, unless the end of 460line is escaped with a backslash 461.Pq Ql \e 462in which case that line and the next are combined. 463.\" The escaped newline is retained and passed to the shell, which 464.\" normally ignores it. 465.\" However, the tab at the beginning of the following line is removed. 466If the first characters of the command are any combination of 467.Ql Ic @ , 468.Ql Ic + , 469or 470.Ql Ic \- , 471the command is treated specially. 472A 473.Ql Ic @ 474causes the command not to be echoed before it is executed. 475A 476.Ql Ic + 477causes the command to be executed even when 478.Fl n 479is given. 480This is similar to the effect of the .MAKE special source, 481except that the effect can be limited to a single line of a script. 482A 483.Ql Ic \- 484in compatibility mode 485causes any non-zero exit status of the command line to be ignored. 486.Pp 487When 488.Nm 489is run in jobs mode with 490.Fl j Ar max_jobs , 491the entire script for the target is fed to a 492single instance of the shell. 493In compatibility (non-jobs) mode, each command is run in a separate process. 494If the command contains any shell meta characters 495.Pq Ql #=|^(){};&<>*?[]:$`\e\en 496it will be passed to the shell; otherwise 497.Nm 498will attempt direct execution. 499If a line starts with 500.Ql Ic \- 501and the shell has ErrCtl enabled then failure of the command line 502will be ignored as in compatibility mode. 503Otherwise 504.Ql Ic \- 505affects the entire job; 506the script will stop at the first command line that fails, 507but the target will not be deemed to have failed. 508.Pp 509Makefiles should be written so that the mode of 510.Nm 511operation does not change their behavior. 512For example, any command which needs to use 513.Dq cd 514or 515.Dq chdir 516without potentially changing the directory for subsequent commands 517should be put in parentheses so it executes in a subshell. 518To force the use of one shell, escape the line breaks so as to make 519the whole script one command. 520For example: 521.Bd -literal -offset indent 522avoid-chdir-side-effects: 523 @echo Building $@ in `pwd` 524 @(cd ${.CURDIR} && ${MAKE} $@) 525 @echo Back in `pwd` 526 527ensure-one-shell-regardless-of-mode: 528 @echo Building $@ in `pwd`; \e 529 (cd ${.CURDIR} && ${MAKE} $@); \e 530 echo Back in `pwd` 531.Ed 532.Pp 533Since 534.Nm 535will 536.Xr chdir 2 537to 538.Ql Va .OBJDIR 539before executing any targets, each child process 540starts with that as its current working directory. 541.Sh VARIABLE ASSIGNMENTS 542Variables in make are much like variables in the shell, and, by tradition, 543consist of all upper-case letters. 544.Ss Variable assignment modifiers 545The five operators that can be used to assign values to variables are as 546follows: 547.Bl -tag -width Ds 548.It Ic \&= 549Assign the value to the variable. 550Any previous value is overridden. 551.It Ic \&+= 552Append the value to the current value of the variable. 553.It Ic \&?= 554Assign the value to the variable if it is not already defined. 555.It Ic \&:= 556Assign with expansion, i.e. expand the value before assigning it 557to the variable. 558Normally, expansion is not done until the variable is referenced. 559.Em NOTE : 560References to undefined variables are 561.Em not 562expanded. 563This can cause problems when variable modifiers are used. 564.It Ic \&!= 565Expand the value and pass it to the shell for execution and assign 566the result to the variable. 567Any newlines in the result are replaced with spaces. 568.El 569.Pp 570Any white-space before the assigned 571.Ar value 572is removed; if the value is being appended, a single space is inserted 573between the previous contents of the variable and the appended value. 574.Pp 575Variables are expanded by surrounding the variable name with either 576curly braces 577.Pq Ql {} 578or parentheses 579.Pq Ql () 580and preceding it with 581a dollar sign 582.Pq Ql \&$ . 583If the variable name contains only a single letter, the surrounding 584braces or parentheses are not required. 585This shorter form is not recommended. 586.Pp 587If the variable name contains a dollar, then the name itself is expanded first. 588This allows almost arbitrary variable names, however names containing dollar, 589braces, parenthesis, or whitespace are really best avoided! 590.Pp 591If the result of expanding a variable contains a dollar sign 592.Pq Ql \&$ 593the string is expanded again. 594.Pp 595Variable substitution occurs at three distinct times, depending on where 596the variable is being used. 597.Bl -enum 598.It 599Variables in dependency lines are expanded as the line is read. 600.It 601Variables in shell commands are expanded when the shell command is 602executed. 603.It 604.Dq .for 605loop index variables are expanded on each loop iteration. 606Note that other variables are not expanded inside loops so 607the following example code: 608.Bd -literal -offset indent 609 610.Dv .for i in 1 2 3 611a+= ${i} 612j= ${i} 613b+= ${j} 614.Dv .endfor 615 616all: 617 @echo ${a} 618 @echo ${b} 619 620.Ed 621will print: 622.Bd -literal -offset indent 6231 2 3 6243 3 3 625 626.Ed 627Because while ${a} contains 628.Dq 1 2 3 629after the loop is executed, ${b} 630contains 631.Dq ${j} ${j} ${j} 632which expands to 633.Dq 3 3 3 634since after the loop completes ${j} contains 635.Dq 3 . 636.El 637.Ss Variable classes 638The four different classes of variables (in order of increasing precedence) 639are: 640.Bl -tag -width Ds 641.It Environment variables 642Variables defined as part of 643.Nm Ns 's 644environment. 645.It Global variables 646Variables defined in the makefile or in included makefiles. 647.It Command line variables 648Variables defined as part of the command line. 649.It Local variables 650Variables that are defined specific to a certain target. 651.El 652.Pp 653Local variables are all built in and their values vary magically from 654target to target. 655It is not currently possible to define new local variables. 656The seven local variables are as follows: 657.Bl -tag -width ".ARCHIVE" -offset indent 658.It Va .ALLSRC 659The list of all sources for this target; also known as 660.Ql Va \&\*[Gt] . 661.It Va .ARCHIVE 662The name of the archive file; also known as 663.Ql Va \&! . 664.It Va .IMPSRC 665In suffix-transformation rules, the name/path of the source from which the 666target is to be transformed (the 667.Dq implied 668source); also known as 669.Ql Va \&\*[Lt] . 670It is not defined in explicit rules. 671.It Va .MEMBER 672The name of the archive member; also known as 673.Ql Va % . 674.It Va .OODATE 675The list of sources for this target that were deemed out-of-date; also 676known as 677.Ql Va \&? . 678.It Va .PREFIX 679The file prefix of the target, containing only the file portion, no suffix 680or preceding directory components; also known as 681.Ql Va * . 682The suffix must be one of the known suffixes declared with 683.Ic .SUFFIXES 684or it will not be recognized. 685.It Va .TARGET 686The name of the target; also known as 687.Ql Va @ . 688For compatibility with other makes this is an alias for 689.Ic .ARCHIVE 690in archive member rules. 691.El 692.Pp 693The shorter forms 694.Ql ( Va \*[Gt] , 695.Ql Va \&! , 696.Ql Va \*[Lt] , 697.Ql Va % , 698.Ql Va \&? , 699.Ql Va * , 700and 701.Ql Va @ ) 702are permitted for backward 703compatibility with historical makefiles and legacy POSIX make and are 704not recommended. 705.Pp 706Variants of these variables with the punctuation followed immediately by 707.Ql D 708or 709.Ql F , 710e.g. 711.Ql Va $(@D) , 712are legacy forms equivalent to using the 713.Ql :H 714and 715.Ql :T 716modifiers. 717These forms are accepted for compatibility with 718.At V 719makefiles and POSIX but are not recommended. 720.Pp 721Four of the local variables may be used in sources on dependency lines 722because they expand to the proper value for each target on the line. 723These variables are 724.Ql Va .TARGET , 725.Ql Va .PREFIX , 726.Ql Va .ARCHIVE , 727and 728.Ql Va .MEMBER . 729.Ss Additional built-in variables 730In addition, 731.Nm 732sets or knows about the following variables: 733.Bl -tag -width .MAKEOVERRIDES 734.It Va \&$ 735A single dollar sign 736.Ql \&$ , 737i.e. 738.Ql \&$$ 739expands to a single dollar 740sign. 741.It Va .ALLTARGETS 742The list of all targets encountered in the Makefile. 743If evaluated during 744Makefile parsing, lists only those targets encountered thus far. 745.It Va .CURDIR 746A path to the directory where 747.Nm 748was executed. 749Refer to the description of 750.Ql Ev PWD 751for more details. 752.It Va .INCLUDEDFROMDIR 753The directory of the file this Makefile was included from. 754.It Va .INCLUDEDFROMFILE 755The filename of the file this Makefile was included from. 756.It Ev MAKE 757The name that 758.Nm 759was executed with 760.Pq Va argv[0] . 761For compatibility 762.Nm 763also sets 764.Va .MAKE 765with the same value. 766The preferred variable to use is the environment variable 767.Ev MAKE 768because it is more compatible with other versions of 769.Nm 770and cannot be confused with the special target with the same name. 771.It Va .MAKE.ALWAYS_PASS_JOB_QUEUE 772Tells 773.Nm 774whether to pass the descriptors of the job token queue 775even if the target is not tagged with 776.Ic .MAKE 777The default is 778.Ql Pa yes 779for backwards compatability with 780.Fx 9.0 781and earlier. 782.It Va .MAKE.DEPENDFILE 783Names the makefile (default 784.Ql Pa .depend ) 785from which generated dependencies are read. 786.It Va .MAKE.EXPAND_VARIABLES 787A boolean that controls the default behavior of the 788.Fl V 789option. 790.It Va .MAKE.EXPORTED 791The list of variables exported by 792.Nm . 793.It Va .MAKE.JOBS 794The argument to the 795.Fl j 796option. 797.It Va .MAKE.JOB.PREFIX 798If 799.Nm 800is run with 801.Ar j 802then output for each target is prefixed with a token 803.Ql --- target --- 804the first part of which can be controlled via 805.Va .MAKE.JOB.PREFIX . 806If 807.Va .MAKE.JOB.PREFIX 808is empty, no token is printed. 809.br 810For example: 811.Li .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}] 812would produce tokens like 813.Ql ---make[1234] target --- 814making it easier to track the degree of parallelism being achieved. 815.It Ev MAKEFLAGS 816The environment variable 817.Ql Ev MAKEFLAGS 818may contain anything that 819may be specified on 820.Nm Ns 's 821command line. 822Anything specified on 823.Nm Ns 's 824command line is appended to the 825.Ql Ev MAKEFLAGS 826variable which is then 827entered into the environment for all programs which 828.Nm 829executes. 830.It Va .MAKE.LEVEL 831The recursion depth of 832.Nm . 833The initial instance of 834.Nm 835will be 0, and an incremented value is put into the environment 836to be seen by the next generation. 837This allows tests like: 838.Li .if ${.MAKE.LEVEL} == 0 839to protect things which should only be evaluated in the initial instance of 840.Nm . 841.It Va .MAKE.MAKEFILE_PREFERENCE 842The ordered list of makefile names 843(default 844.Ql Pa makefile , 845.Ql Pa Makefile ) 846that 847.Nm 848will look for. 849.It Va .MAKE.MAKEFILES 850The list of makefiles read by 851.Nm , 852which is useful for tracking dependencies. 853Each makefile is recorded only once, regardless of the number of times read. 854.It Va .MAKE.MODE 855Processed after reading all makefiles. 856Can affect the mode that 857.Nm 858runs in. 859It can contain a number of keywords: 860.Bl -hang -width ignore-cmd 861.It Pa compat 862Like 863.Fl B , 864puts 865.Nm 866into "compat" mode. 867.It Pa meta 868Puts 869.Nm 870into "meta" mode, where meta files are created for each target 871to capture the command run, the output generated and if 872.Xr filemon 4 873is available, the system calls which are of interest to 874.Nm . 875The captured output can be very useful when diagnosing errors. 876.It Pa curdirOk= Ar bf 877Normally 878.Nm 879will not create .meta files in 880.Ql Va .CURDIR . 881This can be overridden by setting 882.Va bf 883to a value which represents True. 884.It Pa env 885For debugging, it can be useful to include the environment 886in the .meta file. 887.It Pa verbose 888If in "meta" mode, print a clue about the target being built. 889This is useful if the build is otherwise running silently. 890The message printed the value of: 891.Va .MAKE.META.PREFIX . 892.It Pa ignore-cmd 893Some makefiles have commands which are simply not stable. 894This keyword causes them to be ignored for 895determining whether a target is out of date in "meta" mode. 896See also 897.Ic .NOMETA_CMP . 898.It Pa silent= Ar bf 899If 900.Va bf 901is True, when a .meta file is created, mark the target 902.Ic .SILENT . 903.El 904.It Va .MAKE.META.BAILIWICK 905In "meta" mode, provides a list of prefixes which 906match the directories controlled by 907.Nm . 908If a file that was generated outside of 909.Va .OBJDIR 910but within said bailiwick is missing, 911the current target is considered out-of-date. 912.It Va .MAKE.META.CREATED 913In "meta" mode, this variable contains a list of all the meta files 914updated. 915If not empty, it can be used to trigger processing of 916.Va .MAKE.META.FILES . 917.It Va .MAKE.META.FILES 918In "meta" mode, this variable contains a list of all the meta files 919used (updated or not). 920This list can be used to process the meta files to extract dependency 921information. 922.It Va .MAKE.META.IGNORE_PATHS 923Provides a list of path prefixes that should be ignored; 924because the contents are expected to change over time. 925The default list includes: 926.Ql Pa /dev /etc /proc /tmp /var/run /var/tmp 927.It Va .MAKE.META.PREFIX 928Defines the message printed for each meta file updated in "meta verbose" mode. 929The default value is: 930.Dl Building ${.TARGET:H:tA}/${.TARGET:T} 931.It Va .MAKEOVERRIDES 932This variable is used to record the names of variables assigned to 933on the command line, so that they may be exported as part of 934.Ql Ev MAKEFLAGS . 935This behavior can be disabled by assigning an empty value to 936.Ql Va .MAKEOVERRIDES 937within a makefile. 938Extra variables can be exported from a makefile 939by appending their names to 940.Ql Va .MAKEOVERRIDES . 941.Ql Ev MAKEFLAGS 942is re-exported whenever 943.Ql Va .MAKEOVERRIDES 944is modified. 945.It Va .MAKE.PATH_FILEMON 946If 947.Nm 948was built with 949.Xr filemon 4 950support, this is set to the path of the device node. 951This allows makefiles to test for this support. 952.It Va .MAKE.PID 953The process-id of 954.Nm . 955.It Va .MAKE.PPID 956The parent process-id of 957.Nm . 958.It Va .MAKE.SAVE_DOLLARS 959value should be a boolean that controls whether 960.Ql $$ 961are preserved when doing 962.Ql := 963assignments. 964The default is false, for backwards compatibility. 965Set to true for compatability with other makes. 966If set to false, 967.Ql $$ 968becomes 969.Ql $ 970per normal evaluation rules. 971.It Va MAKE_PRINT_VAR_ON_ERROR 972When 973.Nm 974stops due to an error, it prints its name and the value of 975.Ql Va .CURDIR 976as well as the value of any variables named in 977.Ql Va MAKE_PRINT_VAR_ON_ERROR . 978.It Va .newline 979This variable is simply assigned a newline character as its value. 980This allows expansions using the 981.Cm \&:@ 982modifier to put a newline between 983iterations of the loop rather than a space. 984For example, the printing of 985.Ql Va MAKE_PRINT_VAR_ON_ERROR 986could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}. 987.It Va .OBJDIR 988A path to the directory where the targets are built. 989Its value is determined by trying to 990.Xr chdir 2 991to the following directories in order and using the first match: 992.Bl -enum 993.It 994.Ev ${MAKEOBJDIRPREFIX}${.CURDIR} 995.Pp 996(Only if 997.Ql Ev MAKEOBJDIRPREFIX 998is set in the environment or on the command line.) 999.It 1000.Ev ${MAKEOBJDIR} 1001.Pp 1002(Only if 1003.Ql Ev MAKEOBJDIR 1004is set in the environment or on the command line.) 1005.It 1006.Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE} 1007.It 1008.Ev ${.CURDIR} Ns Pa /obj 1009.It 1010.Pa /usr/obj/ Ns Ev ${.CURDIR} 1011.It 1012.Ev ${.CURDIR} 1013.El 1014.Pp 1015Variable expansion is performed on the value before it's used, 1016so expressions such as 1017.Dl ${.CURDIR:S,^/usr/src,/var/obj,} 1018may be used. 1019This is especially useful with 1020.Ql Ev MAKEOBJDIR . 1021.Pp 1022.Ql Va .OBJDIR 1023may be modified in the makefile via the special target 1024.Ql Ic .OBJDIR . 1025In all cases, 1026.Nm 1027will 1028.Xr chdir 2 1029to the specified directory if it exists, and set 1030.Ql Va .OBJDIR 1031and 1032.Ql Ev PWD 1033to that directory before executing any targets. 1034. 1035.It Va .PARSEDIR 1036A path to the directory of the current 1037.Ql Pa Makefile 1038being parsed. 1039.It Va .PARSEFILE 1040The basename of the current 1041.Ql Pa Makefile 1042being parsed. 1043This variable and 1044.Ql Va .PARSEDIR 1045are both set only while the 1046.Ql Pa Makefiles 1047are being parsed. 1048If you want to retain their current values, assign them to a variable 1049using assignment with expansion: 1050.Pq Ql Cm \&:= . 1051.It Va .PATH 1052A variable that represents the list of directories that 1053.Nm 1054will search for files. 1055The search list should be updated using the target 1056.Ql Va .PATH 1057rather than the variable. 1058.It Ev PWD 1059Alternate path to the current directory. 1060.Nm 1061normally sets 1062.Ql Va .CURDIR 1063to the canonical path given by 1064.Xr getcwd 3 . 1065However, if the environment variable 1066.Ql Ev PWD 1067is set and gives a path to the current directory, then 1068.Nm 1069sets 1070.Ql Va .CURDIR 1071to the value of 1072.Ql Ev PWD 1073instead. 1074This behavior is disabled if 1075.Ql Ev MAKEOBJDIRPREFIX 1076is set or 1077.Ql Ev MAKEOBJDIR 1078contains a variable transform. 1079.Ql Ev PWD 1080is set to the value of 1081.Ql Va .OBJDIR 1082for all programs which 1083.Nm 1084executes. 1085.It Ev .TARGETS 1086The list of targets explicitly specified on the command line, if any. 1087.It Ev VPATH 1088Colon-separated 1089.Pq Dq \&: 1090lists of directories that 1091.Nm 1092will search for files. 1093The variable is supported for compatibility with old make programs only, 1094use 1095.Ql Va .PATH 1096instead. 1097.El 1098.Ss Variable modifiers 1099Variable expansion may be modified to select or modify each word of the 1100variable (where a 1101.Dq word 1102is white-space delimited sequence of characters). 1103The general format of a variable expansion is as follows: 1104.Pp 1105.Dl ${variable[:modifier[:...]]} 1106.Pp 1107Each modifier begins with a colon, 1108which may be escaped with a backslash 1109.Pq Ql \e . 1110.Pp 1111A set of modifiers can be specified via a variable, as follows: 1112.Pp 1113.Dl modifier_variable=modifier[:...] 1114.Dl ${variable:${modifier_variable}[:...]} 1115.Pp 1116In this case the first modifier in the modifier_variable does not 1117start with a colon, since that must appear in the referencing 1118variable. 1119If any of the modifiers in the modifier_variable contain a dollar sign 1120.Pq Ql $ , 1121these must be doubled to avoid early expansion. 1122.Pp 1123The supported modifiers are: 1124.Bl -tag -width EEE 1125.It Cm \&:E 1126Replaces each word in the variable with its suffix. 1127.It Cm \&:H 1128Replaces each word in the variable with everything but the last component. 1129.It Cm \&:M Ns Ar pattern 1130Select only those words that match 1131.Ar pattern . 1132The standard shell wildcard characters 1133.Pf ( Ql * , 1134.Ql \&? , 1135and 1136.Ql Oo Oc ) 1137may 1138be used. 1139The wildcard characters may be escaped with a backslash 1140.Pq Ql \e . 1141As a consequence of the way values are split into words, matched, 1142and then joined, a construct like 1143.Dl ${VAR:M*} 1144will normalize the inter-word spacing, removing all leading and 1145trailing space, and converting multiple consecutive spaces 1146to single spaces. 1147. 1148.It Cm \&:N Ns Ar pattern 1149This is identical to 1150.Ql Cm \&:M , 1151but selects all words which do not match 1152.Ar pattern . 1153.It Cm \&:O 1154Order every word in variable alphabetically. 1155To sort words in 1156reverse order use the 1157.Ql Cm \&:O:[-1..1] 1158combination of modifiers. 1159.It Cm \&:Ox 1160Randomize words in variable. 1161The results will be different each time you are referring to the 1162modified variable; use the assignment with expansion 1163.Pq Ql Cm \&:= 1164to prevent such behavior. 1165For example, 1166.Bd -literal -offset indent 1167LIST= uno due tre quattro 1168RANDOM_LIST= ${LIST:Ox} 1169STATIC_RANDOM_LIST:= ${LIST:Ox} 1170 1171all: 1172 @echo "${RANDOM_LIST}" 1173 @echo "${RANDOM_LIST}" 1174 @echo "${STATIC_RANDOM_LIST}" 1175 @echo "${STATIC_RANDOM_LIST}" 1176.Ed 1177may produce output similar to: 1178.Bd -literal -offset indent 1179quattro due tre uno 1180tre due quattro uno 1181due uno quattro tre 1182due uno quattro tre 1183.Ed 1184.It Cm \&:Q 1185Quotes every shell meta-character in the variable, so that it can be passed 1186safely through recursive invocations of 1187.Nm . 1188.It Cm \&:R 1189Replaces each word in the variable with everything but its suffix. 1190.It Cm \&:gmtime 1191The value is a format string for 1192.Xr strftime 3 , 1193using the current 1194.Xr gmtime 3 . 1195.It Cm \&:hash 1196Compute a 32-bit hash of the value and encode it as hex digits. 1197.It Cm \&:localtime 1198The value is a format string for 1199.Xr strftime 3 , 1200using the current 1201.Xr localtime 3 . 1202.It Cm \&:tA 1203Attempt to convert variable to an absolute path using 1204.Xr realpath 3 , 1205if that fails, the value is unchanged. 1206.It Cm \&:tl 1207Converts variable to lower-case letters. 1208.It Cm \&:ts Ns Ar c 1209Words in the variable are normally separated by a space on expansion. 1210This modifier sets the separator to the character 1211.Ar c . 1212If 1213.Ar c 1214is omitted, then no separator is used. 1215The common escapes (including octal numeric codes), work as expected. 1216.It Cm \&:tu 1217Converts variable to upper-case letters. 1218.It Cm \&:tW 1219Causes the value to be treated as a single word 1220(possibly containing embedded white space). 1221See also 1222.Ql Cm \&:[*] . 1223.It Cm \&:tw 1224Causes the value to be treated as a sequence of 1225words delimited by white space. 1226See also 1227.Ql Cm \&:[@] . 1228.Sm off 1229.It Cm \&:S No \&/ Ar old_string No \&/ Ar new_string No \&/ Op Cm 1gW 1230.Sm on 1231Modify the first occurrence of 1232.Ar old_string 1233in the variable's value, replacing it with 1234.Ar new_string . 1235If a 1236.Ql g 1237is appended to the last slash of the pattern, all occurrences 1238in each word are replaced. 1239If a 1240.Ql 1 1241is appended to the last slash of the pattern, only the first word 1242is affected. 1243If a 1244.Ql W 1245is appended to the last slash of the pattern, 1246then the value is treated as a single word 1247(possibly containing embedded white space). 1248If 1249.Ar old_string 1250begins with a caret 1251.Pq Ql ^ , 1252.Ar old_string 1253is anchored at the beginning of each word. 1254If 1255.Ar old_string 1256ends with a dollar sign 1257.Pq Ql \&$ , 1258it is anchored at the end of each word. 1259Inside 1260.Ar new_string , 1261an ampersand 1262.Pq Ql \*[Am] 1263is replaced by 1264.Ar old_string 1265(without any 1266.Ql ^ 1267or 1268.Ql \&$ ) . 1269Any character may be used as a delimiter for the parts of the modifier 1270string. 1271The anchoring, ampersand and delimiter characters may be escaped with a 1272backslash 1273.Pq Ql \e . 1274.Pp 1275Variable expansion occurs in the normal fashion inside both 1276.Ar old_string 1277and 1278.Ar new_string 1279with the single exception that a backslash is used to prevent the expansion 1280of a dollar sign 1281.Pq Ql \&$ , 1282not a preceding dollar sign as is usual. 1283.Sm off 1284.It Cm \&:C No \&/ Ar pattern No \&/ Ar replacement No \&/ Op Cm 1gW 1285.Sm on 1286The 1287.Cm \&:C 1288modifier is just like the 1289.Cm \&:S 1290modifier except that the old and new strings, instead of being 1291simple strings, are an extended regular expression (see 1292.Xr regex 3 ) 1293string 1294.Ar pattern 1295and an 1296.Xr ed 1 Ns \-style 1297string 1298.Ar replacement . 1299Normally, the first occurrence of the pattern 1300.Ar pattern 1301in each word of the value is substituted with 1302.Ar replacement . 1303The 1304.Ql 1 1305modifier causes the substitution to apply to at most one word; the 1306.Ql g 1307modifier causes the substitution to apply to as many instances of the 1308search pattern 1309.Ar pattern 1310as occur in the word or words it is found in; the 1311.Ql W 1312modifier causes the value to be treated as a single word 1313(possibly containing embedded white space). 1314Note that 1315.Ql 1 1316and 1317.Ql g 1318are orthogonal; the former specifies whether multiple words are 1319potentially affected, the latter whether multiple substitutions can 1320potentially occur within each affected word. 1321.Pp 1322As for the 1323.Cm \&:S 1324modifier, the 1325.Ar pattern 1326and 1327.Ar replacement 1328are subjected to variable expansion before being parsed as 1329regular expressions. 1330.It Cm \&:T 1331Replaces each word in the variable with its last component. 1332.It Cm \&:u 1333Remove adjacent duplicate words (like 1334.Xr uniq 1 ) . 1335.Sm off 1336.It Cm \&:\&? Ar true_string Cm \&: Ar false_string 1337.Sm on 1338If the variable name (not its value), when parsed as a .if conditional 1339expression, evaluates to true, return as its value the 1340.Ar true_string , 1341otherwise return the 1342.Ar false_string . 1343Since the variable name is used as the expression, \&:\&? must be the 1344first modifier after the variable name itself - which will, of course, 1345usually contain variable expansions. 1346A common error is trying to use expressions like 1347.Dl ${NUMBERS:M42:?match:no} 1348which actually tests defined(NUMBERS), 1349to determine is any words match "42" you need to use something like: 1350.Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} . 1351.It Ar :old_string=new_string 1352This is the 1353.At V 1354style variable substitution. 1355It must be the last modifier specified. 1356If 1357.Ar old_string 1358or 1359.Ar new_string 1360do not contain the pattern matching character 1361.Ar % 1362then it is assumed that they are 1363anchored at the end of each word, so only suffixes or entire 1364words may be replaced. 1365Otherwise 1366.Ar % 1367is the substring of 1368.Ar old_string 1369to be replaced in 1370.Ar new_string . 1371.Pp 1372Variable expansion occurs in the normal fashion inside both 1373.Ar old_string 1374and 1375.Ar new_string 1376with the single exception that a backslash is used to prevent the 1377expansion of a dollar sign 1378.Pq Ql \&$ , 1379not a preceding dollar sign as is usual. 1380.Sm off 1381.It Cm \&:@ Ar temp Cm @ Ar string Cm @ 1382.Sm on 1383This is the loop expansion mechanism from the OSF Development 1384Environment (ODE) make. 1385Unlike 1386.Cm \&.for 1387loops expansion occurs at the time of 1388reference. 1389Assign 1390.Ar temp 1391to each word in the variable and evaluate 1392.Ar string . 1393The ODE convention is that 1394.Ar temp 1395should start and end with a period. 1396For example. 1397.Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@} 1398.Pp 1399However a single character variable is often more readable: 1400.Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@} 1401.It Cm \&:U Ns Ar newval 1402If the variable is undefined 1403.Ar newval 1404is the value. 1405If the variable is defined, the existing value is returned. 1406This is another ODE make feature. 1407It is handy for setting per-target CFLAGS for instance: 1408.Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}} 1409If a value is only required if the variable is undefined, use: 1410.Dl ${VAR:D:Unewval} 1411.It Cm \&:D Ns Ar newval 1412If the variable is defined 1413.Ar newval 1414is the value. 1415.It Cm \&:L 1416The name of the variable is the value. 1417.It Cm \&:P 1418The path of the node which has the same name as the variable 1419is the value. 1420If no such node exists or its path is null, then the 1421name of the variable is used. 1422In order for this modifier to work, the name (node) must at least have 1423appeared on the rhs of a dependency. 1424.Sm off 1425.It Cm \&:\&! Ar cmd Cm \&! 1426.Sm on 1427The output of running 1428.Ar cmd 1429is the value. 1430.It Cm \&:sh 1431If the variable is non-empty it is run as a command and the output 1432becomes the new value. 1433.It Cm \&::= Ns Ar str 1434The variable is assigned the value 1435.Ar str 1436after substitution. 1437This modifier and its variations are useful in 1438obscure situations such as wanting to set a variable when shell commands 1439are being parsed. 1440These assignment modifiers always expand to 1441nothing, so if appearing in a rule line by themselves should be 1442preceded with something to keep 1443.Nm 1444happy. 1445.Pp 1446The 1447.Ql Cm \&:: 1448helps avoid false matches with the 1449.At V 1450style 1451.Cm \&:= 1452modifier and since substitution always occurs the 1453.Cm \&::= 1454form is vaguely appropriate. 1455.It Cm \&::?= Ns Ar str 1456As for 1457.Cm \&::= 1458but only if the variable does not already have a value. 1459.It Cm \&::+= Ns Ar str 1460Append 1461.Ar str 1462to the variable. 1463.It Cm \&::!= Ns Ar cmd 1464Assign the output of 1465.Ar cmd 1466to the variable. 1467.It Cm \&:\&[ Ns Ar range Ns Cm \&] 1468Selects one or more words from the value, 1469or performs other operations related to the way in which the 1470value is divided into words. 1471.Pp 1472Ordinarily, a value is treated as a sequence of words 1473delimited by white space. 1474Some modifiers suppress this behavior, 1475causing a value to be treated as a single word 1476(possibly containing embedded white space). 1477An empty value, or a value that consists entirely of white-space, 1478is treated as a single word. 1479For the purposes of the 1480.Ql Cm \&:[] 1481modifier, the words are indexed both forwards using positive integers 1482(where index 1 represents the first word), 1483and backwards using negative integers 1484(where index \-1 represents the last word). 1485.Pp 1486The 1487.Ar range 1488is subjected to variable expansion, and the expanded result is 1489then interpreted as follows: 1490.Bl -tag -width index 1491.\" :[n] 1492.It Ar index 1493Selects a single word from the value. 1494.\" :[start..end] 1495.It Ar start Ns Cm \&.. Ns Ar end 1496Selects all words from 1497.Ar start 1498to 1499.Ar end , 1500inclusive. 1501For example, 1502.Ql Cm \&:[2..-1] 1503selects all words from the second word to the last word. 1504If 1505.Ar start 1506is greater than 1507.Ar end , 1508then the words are output in reverse order. 1509For example, 1510.Ql Cm \&:[-1..1] 1511selects all the words from last to first. 1512.\" :[*] 1513.It Cm \&* 1514Causes subsequent modifiers to treat the value as a single word 1515(possibly containing embedded white space). 1516Analogous to the effect of 1517\&"$*\&" 1518in Bourne shell. 1519.\" :[0] 1520.It 0 1521Means the same as 1522.Ql Cm \&:[*] . 1523.\" :[*] 1524.It Cm \&@ 1525Causes subsequent modifiers to treat the value as a sequence of words 1526delimited by white space. 1527Analogous to the effect of 1528\&"$@\&" 1529in Bourne shell. 1530.\" :[#] 1531.It Cm \&# 1532Returns the number of words in the value. 1533.El \" :[range] 1534.El 1535.Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS 1536Makefile inclusion, conditional structures and for loops reminiscent 1537of the C programming language are provided in 1538.Nm . 1539All such structures are identified by a line beginning with a single 1540dot 1541.Pq Ql \&. 1542character. 1543Files are included with either 1544.Cm \&.include Aq Ar file 1545or 1546.Cm \&.include Pf \*q Ar file Ns \*q . 1547Variables between the angle brackets or double quotes are expanded 1548to form the file name. 1549If angle brackets are used, the included makefile is expected to be in 1550the system makefile directory. 1551If double quotes are used, the including makefile's directory and any 1552directories specified using the 1553.Fl I 1554option are searched before the system 1555makefile directory. 1556For compatibility with other versions of 1557.Nm 1558.Ql include file ... 1559is also accepted. 1560.Pp 1561If the include statement is written as 1562.Cm .-include 1563or as 1564.Cm .sinclude 1565then errors locating and/or opening include files are ignored. 1566.Pp 1567If the include statement is written as 1568.Cm .dinclude 1569not only are errors locating and/or opening include files ignored, 1570but stale dependencies within the included file will be ignored 1571just like 1572.Va .MAKE.DEPENDFILE . 1573.Pp 1574Conditional expressions are also preceded by a single dot as the first 1575character of a line. 1576The possible conditionals are as follows: 1577.Bl -tag -width Ds 1578.It Ic .error Ar message 1579The message is printed along with the name of the makefile and line number, 1580then 1581.Nm 1582will exit. 1583.It Ic .export Ar variable ... 1584Export the specified global variable. 1585If no variable list is provided, all globals are exported 1586except for internal variables (those that start with 1587.Ql \&. ) . 1588This is not affected by the 1589.Fl X 1590flag, so should be used with caution. 1591For compatibility with other 1592.Nm 1593programs 1594.Ql export variable=value 1595is also accepted. 1596.Pp 1597Appending a variable name to 1598.Va .MAKE.EXPORTED 1599is equivalent to exporting a variable. 1600.It Ic .export-env Ar variable ... 1601The same as 1602.Ql .export , 1603except that the variable is not appended to 1604.Va .MAKE.EXPORTED . 1605This allows exporting a value to the environment which is different from that 1606used by 1607.Nm 1608internally. 1609.It Ic .export-literal Ar variable ... 1610The same as 1611.Ql .export-env , 1612except that variables in the value are not expanded. 1613.It Ic .info Ar message 1614The message is printed along with the name of the makefile and line number. 1615.It Ic .undef Ar variable 1616Un-define the specified global variable. 1617Only global variables may be un-defined. 1618.It Ic .unexport Ar variable ... 1619The opposite of 1620.Ql .export . 1621The specified global 1622.Va variable 1623will be removed from 1624.Va .MAKE.EXPORTED . 1625If no variable list is provided, all globals are unexported, 1626and 1627.Va .MAKE.EXPORTED 1628deleted. 1629.It Ic .unexport-env 1630Unexport all globals previously exported and 1631clear the environment inherited from the parent. 1632This operation will cause a memory leak of the original environment, 1633so should be used sparingly. 1634Testing for 1635.Va .MAKE.LEVEL 1636being 0, would make sense. 1637Also note that any variables which originated in the parent environment 1638should be explicitly preserved if desired. 1639For example: 1640.Bd -literal -offset indent 1641.Li .if ${.MAKE.LEVEL} == 0 1642PATH := ${PATH} 1643.Li .unexport-env 1644.Li .export PATH 1645.Li .endif 1646.Pp 1647.Ed 1648Would result in an environment containing only 1649.Ql Ev PATH , 1650which is the minimal useful environment. 1651Actually 1652.Ql Ev .MAKE.LEVEL 1653will also be pushed into the new environment. 1654.It Ic .warning Ar message 1655The message prefixed by 1656.Ql Pa warning: 1657is printed along with the name of the makefile and line number. 1658.It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ... 1659Test the value of an expression. 1660.It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1661Test the value of a variable. 1662.It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1663Test the value of a variable. 1664.It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1665Test the target being built. 1666.It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ... 1667Test the target being built. 1668.It Ic .else 1669Reverse the sense of the last conditional. 1670.It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ... 1671A combination of 1672.Ql Ic .else 1673followed by 1674.Ql Ic .if . 1675.It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1676A combination of 1677.Ql Ic .else 1678followed by 1679.Ql Ic .ifdef . 1680.It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1681A combination of 1682.Ql Ic .else 1683followed by 1684.Ql Ic .ifndef . 1685.It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1686A combination of 1687.Ql Ic .else 1688followed by 1689.Ql Ic .ifmake . 1690.It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1691A combination of 1692.Ql Ic .else 1693followed by 1694.Ql Ic .ifnmake . 1695.It Ic .endif 1696End the body of the conditional. 1697.El 1698.Pp 1699The 1700.Ar operator 1701may be any one of the following: 1702.Bl -tag -width "Cm XX" 1703.It Cm \&|\&| 1704Logical OR. 1705.It Cm \&\*[Am]\*[Am] 1706Logical 1707.Tn AND ; 1708of higher precedence than 1709.Dq \&|\&| . 1710.El 1711.Pp 1712As in C, 1713.Nm 1714will only evaluate a conditional as far as is necessary to determine 1715its value. 1716Parentheses may be used to change the order of evaluation. 1717The boolean operator 1718.Ql Ic \&! 1719may be used to logically negate an entire 1720conditional. 1721It is of higher precedence than 1722.Ql Ic \&\*[Am]\*[Am] . 1723.Pp 1724The value of 1725.Ar expression 1726may be any of the following: 1727.Bl -tag -width defined 1728.It Ic defined 1729Takes a variable name as an argument and evaluates to true if the variable 1730has been defined. 1731.It Ic make 1732Takes a target name as an argument and evaluates to true if the target 1733was specified as part of 1734.Nm Ns 's 1735command line or was declared the default target (either implicitly or 1736explicitly, see 1737.Va .MAIN ) 1738before the line containing the conditional. 1739.It Ic empty 1740Takes a variable, with possible modifiers, and evaluates to true if 1741the expansion of the variable would result in an empty string. 1742.It Ic exists 1743Takes a file name as an argument and evaluates to true if the file exists. 1744The file is searched for on the system search path (see 1745.Va .PATH ) . 1746.It Ic target 1747Takes a target name as an argument and evaluates to true if the target 1748has been defined. 1749.It Ic commands 1750Takes a target name as an argument and evaluates to true if the target 1751has been defined and has commands associated with it. 1752.El 1753.Pp 1754.Ar Expression 1755may also be an arithmetic or string comparison. 1756Variable expansion is 1757performed on both sides of the comparison, after which the integral 1758values are compared. 1759A value is interpreted as hexadecimal if it is 1760preceded by 0x, otherwise it is decimal; octal numbers are not supported. 1761The standard C relational operators are all supported. 1762If after 1763variable expansion, either the left or right hand side of a 1764.Ql Ic == 1765or 1766.Ql Ic "!=" 1767operator is not an integral value, then 1768string comparison is performed between the expanded 1769variables. 1770If no relational operator is given, it is assumed that the expanded 1771variable is being compared against 0 or an empty string in the case 1772of a string comparison. 1773.Pp 1774When 1775.Nm 1776is evaluating one of these conditional expressions, and it encounters 1777a (white-space separated) word it doesn't recognize, either the 1778.Dq make 1779or 1780.Dq defined 1781expression is applied to it, depending on the form of the conditional. 1782If the form is 1783.Ql Ic .ifdef , 1784.Ql Ic .ifndef , 1785or 1786.Ql Ic .if 1787the 1788.Dq defined 1789expression is applied. 1790Similarly, if the form is 1791.Ql Ic .ifmake 1792or 1793.Ql Ic .ifnmake , the 1794.Dq make 1795expression is applied. 1796.Pp 1797If the conditional evaluates to true the parsing of the makefile continues 1798as before. 1799If it evaluates to false, the following lines are skipped. 1800In both cases this continues until a 1801.Ql Ic .else 1802or 1803.Ql Ic .endif 1804is found. 1805.Pp 1806For loops are typically used to apply a set of rules to a list of files. 1807The syntax of a for loop is: 1808.Pp 1809.Bl -tag -compact -width Ds 1810.It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression 1811.It Aq make-rules 1812.It Ic \&.endfor 1813.El 1814.Pp 1815After the for 1816.Ic expression 1817is evaluated, it is split into words. 1818On each iteration of the loop, one word is taken and assigned to each 1819.Ic variable , 1820in order, and these 1821.Ic variables 1822are substituted into the 1823.Ic make-rules 1824inside the body of the for loop. 1825The number of words must come out even; that is, if there are three 1826iteration variables, the number of words provided must be a multiple 1827of three. 1828.Sh COMMENTS 1829Comments begin with a hash 1830.Pq Ql \&# 1831character, anywhere but in a shell 1832command line, and continue to the end of an unescaped new line. 1833.Sh SPECIAL SOURCES (ATTRIBUTES) 1834.Bl -tag -width .IGNOREx 1835.It Ic .EXEC 1836Target is never out of date, but always execute commands anyway. 1837.It Ic .IGNORE 1838Ignore any errors from the commands associated with this target, exactly 1839as if they all were preceded by a dash 1840.Pq Ql \- . 1841.\" .It Ic .INVISIBLE 1842.\" XXX 1843.\" .It Ic .JOIN 1844.\" XXX 1845.It Ic .MADE 1846Mark all sources of this target as being up-to-date. 1847.It Ic .MAKE 1848Execute the commands associated with this target even if the 1849.Fl n 1850or 1851.Fl t 1852options were specified. 1853Normally used to mark recursive 1854.Nm Ns s . 1855.It Ic .META 1856Create a meta file for the target, even if it is flagged as 1857.Ic .PHONY , 1858.Ic .MAKE , 1859or 1860.Ic .SPECIAL . 1861Usage in conjunction with 1862.Ic .MAKE 1863is the most likely case. 1864In "meta" mode, the target is out-of-date if the meta file is missing. 1865.It Ic .NOMETA 1866Do not create a meta file for the target. 1867Meta files are also not created for 1868.Ic .PHONY , 1869.Ic .MAKE , 1870or 1871.Ic .SPECIAL 1872targets. 1873.It Ic .NOMETA_CMP 1874Ignore differences in commands when deciding if target is out of date. 1875This is useful if the command contains a value which always changes. 1876If the number of commands change, though, the target will still be out of date. 1877The same effect applies to any command line that uses the variable 1878.Va .OODATE , 1879which can be used for that purpose even when not otherwise needed or desired: 1880.Bd -literal -offset indent 1881 1882skip-compare-for-some: 1883 @echo this will be compared 1884 @echo this will not ${.OODATE:M.NOMETA_CMP} 1885 @echo this will also be compared 1886 1887.Ed 1888The 1889.Cm \&:M 1890pattern suppresses any expansion of the unwanted variable. 1891.It Ic .NOPATH 1892Do not search for the target in the directories specified by 1893.Ic .PATH . 1894.It Ic .NOTMAIN 1895Normally 1896.Nm 1897selects the first target it encounters as the default target to be built 1898if no target was specified. 1899This source prevents this target from being selected. 1900.It Ic .OPTIONAL 1901If a target is marked with this attribute and 1902.Nm 1903can't figure out how to create it, it will ignore this fact and assume 1904the file isn't needed or already exists. 1905.It Ic .PHONY 1906The target does not 1907correspond to an actual file; it is always considered to be out of date, 1908and will not be created with the 1909.Fl t 1910option. 1911Suffix-transformation rules are not applied to 1912.Ic .PHONY 1913targets. 1914.It Ic .PRECIOUS 1915When 1916.Nm 1917is interrupted, it normally removes any partially made targets. 1918This source prevents the target from being removed. 1919.It Ic .RECURSIVE 1920Synonym for 1921.Ic .MAKE . 1922.It Ic .SILENT 1923Do not echo any of the commands associated with this target, exactly 1924as if they all were preceded by an at sign 1925.Pq Ql @ . 1926.It Ic .USE 1927Turn the target into 1928.Nm Ns 's 1929version of a macro. 1930When the target is used as a source for another target, the other target 1931acquires the commands, sources, and attributes (except for 1932.Ic .USE ) 1933of the 1934source. 1935If the target already has commands, the 1936.Ic .USE 1937target's commands are appended 1938to them. 1939.It Ic .USEBEFORE 1940Exactly like 1941.Ic .USE , 1942but prepend the 1943.Ic .USEBEFORE 1944target commands to the target. 1945.It Ic .WAIT 1946If 1947.Ic .WAIT 1948appears in a dependency line, the sources that precede it are 1949made before the sources that succeed it in the line. 1950Since the dependents of files are not made until the file itself 1951could be made, this also stops the dependents being built unless they 1952are needed for another branch of the dependency tree. 1953So given: 1954.Bd -literal 1955x: a .WAIT b 1956 echo x 1957a: 1958 echo a 1959b: b1 1960 echo b 1961b1: 1962 echo b1 1963 1964.Ed 1965the output is always 1966.Ql a , 1967.Ql b1 , 1968.Ql b , 1969.Ql x . 1970.br 1971The ordering imposed by 1972.Ic .WAIT 1973is only relevant for parallel makes. 1974.El 1975.Sh SPECIAL TARGETS 1976Special targets may not be included with other targets, i.e. they must be 1977the only target specified. 1978.Bl -tag -width .BEGINx 1979.It Ic .BEGIN 1980Any command lines attached to this target are executed before anything 1981else is done. 1982.It Ic .DEFAULT 1983This is sort of a 1984.Ic .USE 1985rule for any target (that was used only as a 1986source) that 1987.Nm 1988can't figure out any other way to create. 1989Only the shell script is used. 1990The 1991.Ic .IMPSRC 1992variable of a target that inherits 1993.Ic .DEFAULT Ns 's 1994commands is set 1995to the target's own name. 1996.It Ic .END 1997Any command lines attached to this target are executed after everything 1998else is done. 1999.It Ic .ERROR 2000Any command lines attached to this target are executed when another target fails. 2001The 2002.Ic .ERROR_TARGET 2003variable is set to the target that failed. 2004See also 2005.Ic MAKE_PRINT_VAR_ON_ERROR . 2006.It Ic .IGNORE 2007Mark each of the sources with the 2008.Ic .IGNORE 2009attribute. 2010If no sources are specified, this is the equivalent of specifying the 2011.Fl i 2012option. 2013.It Ic .INTERRUPT 2014If 2015.Nm 2016is interrupted, the commands for this target will be executed. 2017.It Ic .MAIN 2018If no target is specified when 2019.Nm 2020is invoked, this target will be built. 2021.It Ic .MAKEFLAGS 2022This target provides a way to specify flags for 2023.Nm 2024when the makefile is used. 2025The flags are as if typed to the shell, though the 2026.Fl f 2027option will have 2028no effect. 2029.\" XXX: NOT YET!!!! 2030.\" .It Ic .NOTPARALLEL 2031.\" The named targets are executed in non parallel mode. 2032.\" If no targets are 2033.\" specified, then all targets are executed in non parallel mode. 2034.It Ic .NOPATH 2035Apply the 2036.Ic .NOPATH 2037attribute to any specified sources. 2038.It Ic .NOTPARALLEL 2039Disable parallel mode. 2040.It Ic .NO_PARALLEL 2041Synonym for 2042.Ic .NOTPARALLEL , 2043for compatibility with other pmake variants. 2044.It Ic .OBJDIR 2045The source is a new value for 2046.Ql Va .OBJDIR . 2047If it exists, 2048.Nm 2049will 2050.Xr chdir 2 2051to it and update the value of 2052.Ql Va .OBJDIR . 2053.It Ic .ORDER 2054The named targets are made in sequence. 2055This ordering does not add targets to the list of targets to be made. 2056Since the dependents of a target do not get built until the target itself 2057could be built, unless 2058.Ql a 2059is built by another part of the dependency graph, 2060the following is a dependency loop: 2061.Bd -literal 2062\&.ORDER: b a 2063b: a 2064.Ed 2065.Pp 2066The ordering imposed by 2067.Ic .ORDER 2068is only relevant for parallel makes. 2069.\" XXX: NOT YET!!!! 2070.\" .It Ic .PARALLEL 2071.\" The named targets are executed in parallel mode. 2072.\" If no targets are 2073.\" specified, then all targets are executed in parallel mode. 2074.It Ic .PATH 2075The sources are directories which are to be searched for files not 2076found in the current directory. 2077If no sources are specified, any previously specified directories are 2078deleted. 2079If the source is the special 2080.Ic .DOTLAST 2081target, then the current working 2082directory is searched last. 2083.It Ic .PATH. Ns Va suffix 2084Like 2085.Ic .PATH 2086but applies only to files with a particular suffix. 2087The suffix must have been previously declared with 2088.Ic .SUFFIXES . 2089.It Ic .PHONY 2090Apply the 2091.Ic .PHONY 2092attribute to any specified sources. 2093.It Ic .PRECIOUS 2094Apply the 2095.Ic .PRECIOUS 2096attribute to any specified sources. 2097If no sources are specified, the 2098.Ic .PRECIOUS 2099attribute is applied to every 2100target in the file. 2101.It Ic .SHELL 2102Sets the shell that 2103.Nm 2104will use to execute commands. 2105The sources are a set of 2106.Ar field=value 2107pairs. 2108.Bl -tag -width hasErrCtls 2109.It Ar name 2110This is the minimal specification, used to select one of the built-in 2111shell specs; 2112.Ar sh , 2113.Ar ksh , 2114and 2115.Ar csh . 2116.It Ar path 2117Specifies the path to the shell. 2118.It Ar hasErrCtl 2119Indicates whether the shell supports exit on error. 2120.It Ar check 2121The command to turn on error checking. 2122.It Ar ignore 2123The command to disable error checking. 2124.It Ar echo 2125The command to turn on echoing of commands executed. 2126.It Ar quiet 2127The command to turn off echoing of commands executed. 2128.It Ar filter 2129The output to filter after issuing the 2130.Ar quiet 2131command. 2132It is typically identical to 2133.Ar quiet . 2134.It Ar errFlag 2135The flag to pass the shell to enable error checking. 2136.It Ar echoFlag 2137The flag to pass the shell to enable command echoing. 2138.It Ar newline 2139The string literal to pass the shell that results in a single newline 2140character when used outside of any quoting characters. 2141.El 2142Example: 2143.Bd -literal 2144\&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e 2145 check="set \-e" ignore="set +e" \e 2146 echo="set \-v" quiet="set +v" filter="set +v" \e 2147 echoFlag=v errFlag=e newline="'\en'" 2148.Ed 2149.It Ic .SILENT 2150Apply the 2151.Ic .SILENT 2152attribute to any specified sources. 2153If no sources are specified, the 2154.Ic .SILENT 2155attribute is applied to every 2156command in the file. 2157.It Ic .STALE 2158This target gets run when a dependency file contains stale entries, having 2159.Va .ALLSRC 2160set to the name of that dependency file. 2161.It Ic .SUFFIXES 2162Each source specifies a suffix to 2163.Nm . 2164If no sources are specified, any previously specified suffixes are deleted. 2165It allows the creation of suffix-transformation rules. 2166.Pp 2167Example: 2168.Bd -literal 2169\&.SUFFIXES: .o 2170\&.c.o: 2171 cc \-o ${.TARGET} \-c ${.IMPSRC} 2172.Ed 2173.El 2174.Sh ENVIRONMENT 2175.Nm 2176uses the following environment variables, if they exist: 2177.Ev MACHINE , 2178.Ev MACHINE_ARCH , 2179.Ev MAKE , 2180.Ev MAKEFLAGS , 2181.Ev MAKEOBJDIR , 2182.Ev MAKEOBJDIRPREFIX , 2183.Ev MAKESYSPATH , 2184.Ev PWD , 2185and 2186.Ev TMPDIR . 2187.Pp 2188.Ev MAKEOBJDIRPREFIX 2189and 2190.Ev MAKEOBJDIR 2191may only be set in the environment or on the command line to 2192.Nm 2193and not as makefile variables; 2194see the description of 2195.Ql Va .OBJDIR 2196for more details. 2197.Sh FILES 2198.Bl -tag -width /usr/share/mk -compact 2199.It .depend 2200list of dependencies 2201.It Makefile 2202list of dependencies 2203.It makefile 2204list of dependencies 2205.It sys.mk 2206system makefile 2207.It /usr/share/mk 2208system makefile directory 2209.El 2210.Sh COMPATIBILITY 2211The basic make syntax is compatible between different versions of make; 2212however the special variables, variable modifiers and conditionals are not. 2213.Ss Older versions 2214An incomplete list of changes in older versions of 2215.Nm : 2216.Pp 2217The way that .for loop variables are substituted changed after 2218.Nx 5.0 2219so that they still appear to be variable expansions. 2220In particular this stops them being treated as syntax, and removes some 2221obscure problems using them in .if statements. 2222.Pp 2223The way that parallel makes are scheduled changed in 2224.Nx 4.0 2225so that .ORDER and .WAIT apply recursively to the dependent nodes. 2226The algorithms used may change again in the future. 2227.Ss Other make dialects 2228Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not 2229support most of the features of 2230.Nm 2231as described in this manual. 2232Most notably: 2233.Bl -bullet -offset indent 2234.It 2235The 2236.Ic .WAIT 2237and 2238.Ic .ORDER 2239declarations and most functionality pertaining to parallelization. 2240(GNU make supports parallelization but lacks these features needed to 2241control it effectively.) 2242.It 2243Directives, including for loops and conditionals and most of the 2244forms of include files. 2245(GNU make has its own incompatible and less powerful syntax for 2246conditionals.) 2247.It 2248All built-in variables that begin with a dot. 2249.It 2250Most of the special sources and targets that begin with a dot, 2251with the notable exception of 2252.Ic .PHONY , 2253.Ic .PRECIOUS , 2254and 2255.Ic .SUFFIXES . 2256.It 2257Variable modifiers, except for the 2258.Dl :old=new 2259string substitution, which does not portably support globbing with 2260.Ql % 2261and historically only works on declared suffixes. 2262.It 2263The 2264.Ic $> 2265variable even in its short form; most makes support this functionality 2266but its name varies. 2267.El 2268.Pp 2269Some features are somewhat more portable, such as assignment with 2270.Ic += , 2271.Ic ?= , 2272and 2273.Ic != . 2274The 2275.Ic .PATH 2276functionality is based on an older feature 2277.Ic VPATH 2278found in GNU make and many versions of SVR4 make; however, 2279historically its behavior is too ill-defined (and too buggy) to rely 2280upon. 2281.Pp 2282The 2283.Ic $@ 2284and 2285.Ic $< 2286variables are more or less universally portable, as is the 2287.Ic $(MAKE) 2288variable. 2289Basic use of suffix rules (for files only in the current directory, 2290not trying to chain transformations together, etc.) is also reasonably 2291portable. 2292.Sh SEE ALSO 2293.Xr mkdep 1 2294.Sh HISTORY 2295A 2296.Nm 2297command appeared in 2298.At v7 . 2299This 2300.Nm 2301implementation is based on Adam De Boor's pmake program which was written 2302for Sprite at Berkeley. 2303It was designed to be a parallel distributed make running jobs on different 2304machines using a daemon called 2305.Dq customs . 2306.Pp 2307Historically the target/dependency 2308.Dq FRC 2309has been used to FoRCe rebuilding (since the target/dependency 2310does not exist... unless someone creates an 2311.Dq FRC 2312file). 2313.Sh BUGS 2314The 2315.Nm 2316syntax is difficult to parse without actually acting of the data. 2317For instance finding the end of a variable use should involve scanning each 2318the modifiers using the correct terminator for each field. 2319In many places 2320.Nm 2321just counts {} and () in order to find the end of a variable expansion. 2322.Pp 2323There is no way of escaping a space character in a filename. 2324