1.\" $NetBSD: make.1,v 1.243 2014/09/14 08:47:19 apb 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 September 13, 2014 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 filesystem. 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 \- 484causes any non-zero exit status of the command line to be ignored. 485.Pp 486When 487.Nm 488is run in jobs mode with 489.Fl j Ar max_jobs , 490the entire script for the target is fed to a 491single instance of the shell. 492In compatibility (non-jobs) mode, each command is run in a separate process. 493If the command contains any shell meta characters 494.Pq Ql #=|^(){};&<>*?[]:$`\e\en 495it will be passed to the shell; otherwise 496.Nm 497will attempt direct execution. 498.Pp 499Makefiles should be written so that the mode of 500.Nm 501operation does not change their behavior. 502For example, any command which needs to use 503.Dq cd 504or 505.Dq chdir 506without potentially changing the directory for subsequent commands 507should be put in parentheses so it executes in a subshell. 508To force the use of one shell, escape the line breaks so as to make 509the whole script one command. 510For example: 511.Bd -literal -offset indent 512avoid-chdir-side-effects: 513 @echo Building $@ in `pwd` 514 @(cd ${.CURDIR} && ${MAKE} $@) 515 @echo Back in `pwd` 516 517ensure-one-shell-regardless-of-mode: 518 @echo Building $@ in `pwd`; \e 519 (cd ${.CURDIR} && ${MAKE} $@); \e 520 echo Back in `pwd` 521.Ed 522.Pp 523Since 524.Nm 525will 526.Xr chdir 2 527to 528.Ql Va .OBJDIR 529before executing any targets, each child process 530starts with that as its current working directory. 531.Sh VARIABLE ASSIGNMENTS 532Variables in make are much like variables in the shell, and, by tradition, 533consist of all upper-case letters. 534.Ss Variable assignment modifiers 535The five operators that can be used to assign values to variables are as 536follows: 537.Bl -tag -width Ds 538.It Ic \&= 539Assign the value to the variable. 540Any previous value is overridden. 541.It Ic \&+= 542Append the value to the current value of the variable. 543.It Ic \&?= 544Assign the value to the variable if it is not already defined. 545.It Ic \&:= 546Assign with expansion, i.e. expand the value before assigning it 547to the variable. 548Normally, expansion is not done until the variable is referenced. 549.Em NOTE : 550References to undefined variables are 551.Em not 552expanded. 553This can cause problems when variable modifiers are used. 554.It Ic \&!= 555Expand the value and pass it to the shell for execution and assign 556the result to the variable. 557Any newlines in the result are replaced with spaces. 558.El 559.Pp 560Any white-space before the assigned 561.Ar value 562is removed; if the value is being appended, a single space is inserted 563between the previous contents of the variable and the appended value. 564.Pp 565Variables are expanded by surrounding the variable name with either 566curly braces 567.Pq Ql {} 568or parentheses 569.Pq Ql () 570and preceding it with 571a dollar sign 572.Pq Ql \&$ . 573If the variable name contains only a single letter, the surrounding 574braces or parentheses are not required. 575This shorter form is not recommended. 576.Pp 577If the variable name contains a dollar, then the name itself is expanded first. 578This allows almost arbitrary variable names, however names containing dollar, 579braces, parenthesis, or whitespace are really best avoided! 580.Pp 581If the result of expanding a variable contains a dollar sign 582.Pq Ql \&$ 583the string is expanded again. 584.Pp 585Variable substitution occurs at three distinct times, depending on where 586the variable is being used. 587.Bl -enum 588.It 589Variables in dependency lines are expanded as the line is read. 590.It 591Variables in shell commands are expanded when the shell command is 592executed. 593.It 594.Dq .for 595loop index variables are expanded on each loop iteration. 596Note that other variables are not expanded inside loops so 597the following example code: 598.Bd -literal -offset indent 599 600.Dv .for i in 1 2 3 601a+= ${i} 602j= ${i} 603b+= ${j} 604.Dv .endfor 605 606all: 607 @echo ${a} 608 @echo ${b} 609 610.Ed 611will print: 612.Bd -literal -offset indent 6131 2 3 6143 3 3 615 616.Ed 617Because while ${a} contains 618.Dq 1 2 3 619after the loop is executed, ${b} 620contains 621.Dq ${j} ${j} ${j} 622which expands to 623.Dq 3 3 3 624since after the loop completes ${j} contains 625.Dq 3 . 626.El 627.Ss Variable classes 628The four different classes of variables (in order of increasing precedence) 629are: 630.Bl -tag -width Ds 631.It Environment variables 632Variables defined as part of 633.Nm Ns 's 634environment. 635.It Global variables 636Variables defined in the makefile or in included makefiles. 637.It Command line variables 638Variables defined as part of the command line. 639.It Local variables 640Variables that are defined specific to a certain target. 641.El 642.Pp 643Local variables are all built in and their values vary magically from 644target to target. 645It is not currently possible to define new local variables. 646The seven local variables are as follows: 647.Bl -tag -width ".ARCHIVE" -offset indent 648.It Va .ALLSRC 649The list of all sources for this target; also known as 650.Ql Va \&\*[Gt] . 651.It Va .ARCHIVE 652The name of the archive file; also known as 653.Ql Va \&! . 654.It Va .IMPSRC 655In suffix-transformation rules, the name/path of the source from which the 656target is to be transformed (the 657.Dq implied 658source); also known as 659.Ql Va \&\*[Lt] . 660It is not defined in explicit rules. 661.It Va .MEMBER 662The name of the archive member; also known as 663.Ql Va % . 664.It Va .OODATE 665The list of sources for this target that were deemed out-of-date; also 666known as 667.Ql Va \&? . 668.It Va .PREFIX 669The file prefix of the target, containing only the file portion, no suffix 670or preceding directory components; also known as 671.Ql Va * . 672The suffix must be one of the known suffixes declared with 673.Ic .SUFFIXES 674or it will not be recognized. 675.It Va .TARGET 676The name of the target; also known as 677.Ql Va @ . 678.El 679.Pp 680The shorter forms 681.Ql ( Va \*[Gt] , 682.Ql Va \&! , 683.Ql Va \*[Lt] , 684.Ql Va % , 685.Ql Va \&? , 686.Ql Va * , 687and 688.Ql Va @ ) 689are permitted for backward 690compatibility with historical makefiles and legacy POSIX make and are 691not recommended. 692.Pp 693Variants of these variables with the punctuation followed immediately by 694.Ql D 695or 696.Ql F , 697e.g. 698.Ql Va $(@D) , 699are legacy forms equivalent to using the 700.Ql :H 701and 702.Ql :T 703modifiers. 704These forms are accepted for compatibility with 705.At V 706makefiles and POSIX but are not recommended. 707.Pp 708Four of the local variables may be used in sources on dependency lines 709because they expand to the proper value for each target on the line. 710These variables are 711.Ql Va .TARGET , 712.Ql Va .PREFIX , 713.Ql Va .ARCHIVE , 714and 715.Ql Va .MEMBER . 716.Ss Additional built-in variables 717In addition, 718.Nm 719sets or knows about the following variables: 720.Bl -tag -width .MAKEOVERRIDES 721.It Va \&$ 722A single dollar sign 723.Ql \&$ , 724i.e. 725.Ql \&$$ 726expands to a single dollar 727sign. 728.It Va .ALLTARGETS 729The list of all targets encountered in the Makefile. 730If evaluated during 731Makefile parsing, lists only those targets encountered thus far. 732.It Va .CURDIR 733A path to the directory where 734.Nm 735was executed. 736Refer to the description of 737.Ql Ev PWD 738for more details. 739.It Va .INCLUDEDFROMDIR 740The directory of the file this Makefile was included from. 741.It Va .INCLUDEDFROMFILE 742The filename of the file this Makefile was included from. 743.It Ev MAKE 744The name that 745.Nm 746was executed with 747.Pq Va argv[0] . 748For compatibility 749.Nm 750also sets 751.Va .MAKE 752with the same value. 753The preferred variable to use is the environment variable 754.Ev MAKE 755because it is more compatible with other versions of 756.Nm 757and cannot be confused with the special target with the same name. 758.It Va .MAKE.DEPENDFILE 759Names the makefile (default 760.Ql Pa .depend ) 761from which generated dependencies are read. 762.It Va .MAKE.EXPAND_VARIABLES 763A boolean that controls the default behavior of the 764.Fl V 765option. 766.It Va .MAKE.EXPORTED 767The list of variables exported by 768.Nm . 769.It Va .MAKE.JOBS 770The argument to the 771.Fl j 772option. 773.It Va .MAKE.JOB.PREFIX 774If 775.Nm 776is run with 777.Ar j 778then output for each target is prefixed with a token 779.Ql --- target --- 780the first part of which can be controlled via 781.Va .MAKE.JOB.PREFIX . 782If 783.Va .MAKE.JOB.PREFIX 784is empty, no token is printed. 785.br 786For example: 787.Li .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}] 788would produce tokens like 789.Ql ---make[1234] target --- 790making it easier to track the degree of parallelism being achieved. 791.It Ev MAKEFLAGS 792The environment variable 793.Ql Ev MAKEFLAGS 794may contain anything that 795may be specified on 796.Nm Ns 's 797command line. 798Anything specified on 799.Nm Ns 's 800command line is appended to the 801.Ql Ev MAKEFLAGS 802variable which is then 803entered into the environment for all programs which 804.Nm 805executes. 806.It Va .MAKE.LEVEL 807The recursion depth of 808.Nm . 809The initial instance of 810.Nm 811will be 0, and an incremented value is put into the environment 812to be seen by the next generation. 813This allows tests like: 814.Li .if ${.MAKE.LEVEL} == 0 815to protect things which should only be evaluated in the initial instance of 816.Nm . 817.It Va .MAKE.MAKEFILE_PREFERENCE 818The ordered list of makefile names 819(default 820.Ql Pa makefile , 821.Ql Pa Makefile ) 822that 823.Nm 824will look for. 825.It Va .MAKE.MAKEFILES 826The list of makefiles read by 827.Nm , 828which is useful for tracking dependencies. 829Each makefile is recorded only once, regardless of the number of times read. 830.It Va .MAKE.MODE 831Processed after reading all makefiles. 832Can affect the mode that 833.Nm 834runs in. 835It can contain a number of keywords: 836.Bl -hang -width ignore-cmd 837.It Pa compat 838Like 839.Fl B , 840puts 841.Nm 842into "compat" mode. 843.It Pa meta 844Puts 845.Nm 846into "meta" mode, where meta files are created for each target 847to capture the command run, the output generated and if 848.Xr filemon 4 849is available, the system calls which are of interest to 850.Nm . 851The captured output can be very useful when diagnosing errors. 852.It Pa curdirOk= Ar bf 853Normally 854.Nm 855will not create .meta files in 856.Ql Va .CURDIR . 857This can be overridden by setting 858.Va bf 859to a value which represents True. 860.It Pa env 861For debugging, it can be useful to inlcude the environment 862in the .meta file. 863.It Pa verbose 864If in "meta" mode, print a clue about the target being built. 865This is useful if the build is otherwise running silently. 866The message printed the value of: 867.Va .MAKE.META.PREFIX . 868.It Pa ignore-cmd 869Some makefiles have commands which are simply not stable. 870This keyword causes them to be ignored for 871determining whether a target is out of date in "meta" mode. 872See also 873.Ic .NOMETA_CMP . 874.It Pa silent= Ar bf 875If 876.Va bf 877is True, when a .meta file is created, mark the target 878.Ic .SILENT . 879.El 880.It Va .MAKE.META.BAILIWICK 881In "meta" mode, provides a list of prefixes which 882match the directories controlled by 883.Nm . 884If a file that was generated outside of 885.Va .OBJDIR 886but within said bailiwick is missing, 887the current target is considered out-of-date. 888.It Va .MAKE.META.CREATED 889In "meta" mode, this variable contains a list of all the meta files 890updated. 891If not empty, it can be used to trigger processing of 892.Va .MAKE.META.FILES . 893.It Va .MAKE.META.FILES 894In "meta" mode, this variable contains a list of all the meta files 895used (updated or not). 896This list can be used to process the meta files to extract dependency 897information. 898.It Va .MAKE.META.IGNORE_PATHS 899Provides a list of path prefixes that should be ignored; 900because the contents are expected to change over time. 901The default list includes: 902.Ql Pa /dev /etc /proc /tmp /var/run /var/tmp 903.It Va .MAKE.META.PREFIX 904Defines the message printed for each meta file updated in "meta verbose" mode. 905The default value is: 906.Dl Building ${.TARGET:H:tA}/${.TARGET:T} 907.It Va .MAKEOVERRIDES 908This variable is used to record the names of variables assigned to 909on the command line, so that they may be exported as part of 910.Ql Ev MAKEFLAGS . 911This behaviour can be disabled by assigning an empty value to 912.Ql Va .MAKEOVERRIDES 913within a makefile. 914Extra variables can be exported from a makefile 915by appending their names to 916.Ql Va .MAKEOVERRIDES . 917.Ql Ev MAKEFLAGS 918is re-exported whenever 919.Ql Va .MAKEOVERRIDES 920is modified. 921.It Va .MAKE.PATH_FILEMON 922If 923.Nm 924was built with 925.Xr filemon 4 926support, this is set to the path of the device node. 927This allows makefiles to test for this support. 928.It Va .MAKE.PID 929The process-id of 930.Nm . 931.It Va .MAKE.PPID 932The parent process-id of 933.Nm . 934.It Va MAKE_PRINT_VAR_ON_ERROR 935When 936.Nm 937stops due to an error, it prints its name and the value of 938.Ql Va .CURDIR 939as well as the value of any variables named in 940.Ql Va MAKE_PRINT_VAR_ON_ERROR . 941.It Va .newline 942This variable is simply assigned a newline character as its value. 943This allows expansions using the 944.Cm \&:@ 945modifier to put a newline between 946iterations of the loop rather than a space. 947For example, the printing of 948.Ql Va MAKE_PRINT_VAR_ON_ERROR 949could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}. 950.It Va .OBJDIR 951A path to the directory where the targets are built. 952Its value is determined by trying to 953.Xr chdir 2 954to the following directories in order and using the first match: 955.Bl -enum 956.It 957.Ev ${MAKEOBJDIRPREFIX}${.CURDIR} 958.Pp 959(Only if 960.Ql Ev MAKEOBJDIRPREFIX 961is set in the environment or on the command line.) 962.It 963.Ev ${MAKEOBJDIR} 964.Pp 965(Only if 966.Ql Ev MAKEOBJDIR 967is set in the environment or on the command line.) 968.It 969.Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE} 970.It 971.Ev ${.CURDIR} Ns Pa /obj 972.It 973.Pa /usr/obj/ Ns Ev ${.CURDIR} 974.It 975.Ev ${.CURDIR} 976.El 977.Pp 978Variable expansion is performed on the value before it's used, 979so expressions such as 980.Dl ${.CURDIR:S,^/usr/src,/var/obj,} 981may be used. 982This is especially useful with 983.Ql Ev MAKEOBJDIR . 984.Pp 985.Ql Va .OBJDIR 986may be modified in the makefile as a global variable. 987In all cases, 988.Nm 989will 990.Xr chdir 2 991to 992.Ql Va .OBJDIR 993and set 994.Ql Ev PWD 995to that directory before executing any targets. 996. 997.It Va .PARSEDIR 998A path to the directory of the current 999.Ql Pa Makefile 1000being parsed. 1001.It Va .PARSEFILE 1002The basename of the current 1003.Ql Pa Makefile 1004being parsed. 1005This variable and 1006.Ql Va .PARSEDIR 1007are both set only while the 1008.Ql Pa Makefiles 1009are being parsed. 1010If you want to retain their current values, assign them to a variable 1011using assignment with expansion: 1012.Pq Ql Cm \&:= . 1013.It Va .PATH 1014A variable that represents the list of directories that 1015.Nm 1016will search for files. 1017The search list should be updated using the target 1018.Ql Va .PATH 1019rather than the variable. 1020.It Ev PWD 1021Alternate path to the current directory. 1022.Nm 1023normally sets 1024.Ql Va .CURDIR 1025to the canonical path given by 1026.Xr getcwd 3 . 1027However, if the environment variable 1028.Ql Ev PWD 1029is set and gives a path to the current directory, then 1030.Nm 1031sets 1032.Ql Va .CURDIR 1033to the value of 1034.Ql Ev PWD 1035instead. 1036This behaviour is disabled if 1037.Ql Ev MAKEOBJDIRPREFIX 1038is set or 1039.Ql Ev MAKEOBJDIR 1040contains a variable transform. 1041.Ql Ev PWD 1042is set to the value of 1043.Ql Va .OBJDIR 1044for all programs which 1045.Nm 1046executes. 1047.It Ev .TARGETS 1048The list of targets explicitly specified on the command line, if any. 1049.It Ev VPATH 1050Colon-separated 1051.Pq Dq \&: 1052lists of directories that 1053.Nm 1054will search for files. 1055The variable is supported for compatibility with old make programs only, 1056use 1057.Ql Va .PATH 1058instead. 1059.El 1060.Ss Variable modifiers 1061Variable expansion may be modified to select or modify each word of the 1062variable (where a 1063.Dq word 1064is white-space delimited sequence of characters). 1065The general format of a variable expansion is as follows: 1066.Pp 1067.Dl ${variable[:modifier[:...]]} 1068.Pp 1069Each modifier begins with a colon, 1070which may be escaped with a backslash 1071.Pq Ql \e . 1072.Pp 1073A set of modifiers can be specified via a variable, as follows: 1074.Pp 1075.Dl modifier_variable=modifier[:...] 1076.Dl ${variable:${modifier_variable}[:...]} 1077.Pp 1078In this case the first modifier in the modifier_variable does not 1079start with a colon, since that must appear in the referencing 1080variable. 1081If any of the modifiers in the modifier_variable contain a dollar sign 1082.Pq Ql $ , 1083these must be doubled to avoid early expansion. 1084.Pp 1085The supported modifiers are: 1086.Bl -tag -width EEE 1087.It Cm \&:E 1088Replaces each word in the variable with its suffix. 1089.It Cm \&:H 1090Replaces each word in the variable with everything but the last component. 1091.It Cm \&:M Ns Ar pattern 1092Select only those words that match 1093.Ar pattern . 1094The standard shell wildcard characters 1095.Pf ( Ql * , 1096.Ql \&? , 1097and 1098.Ql Oo Oc ) 1099may 1100be used. 1101The wildcard characters may be escaped with a backslash 1102.Pq Ql \e . 1103As a consequence of the way values are split into words, matched, 1104and then joined, a construct like 1105.Dl ${VAR:M*} 1106will normalise the inter-word spacing, removing all leading and 1107trailing space, and converting multiple consecutive spaces 1108to single spaces. 1109. 1110.It Cm \&:N Ns Ar pattern 1111This is identical to 1112.Ql Cm \&:M , 1113but selects all words which do not match 1114.Ar pattern . 1115.It Cm \&:O 1116Order every word in variable alphabetically. 1117To sort words in 1118reverse order use the 1119.Ql Cm \&:O:[-1..1] 1120combination of modifiers. 1121.It Cm \&:Ox 1122Randomize words in variable. 1123The results will be different each time you are referring to the 1124modified variable; use the assignment with expansion 1125.Pq Ql Cm \&:= 1126to prevent such behaviour. 1127For example, 1128.Bd -literal -offset indent 1129LIST= uno due tre quattro 1130RANDOM_LIST= ${LIST:Ox} 1131STATIC_RANDOM_LIST:= ${LIST:Ox} 1132 1133all: 1134 @echo "${RANDOM_LIST}" 1135 @echo "${RANDOM_LIST}" 1136 @echo "${STATIC_RANDOM_LIST}" 1137 @echo "${STATIC_RANDOM_LIST}" 1138.Ed 1139may produce output similar to: 1140.Bd -literal -offset indent 1141quattro due tre uno 1142tre due quattro uno 1143due uno quattro tre 1144due uno quattro tre 1145.Ed 1146.It Cm \&:Q 1147Quotes every shell meta-character in the variable, so that it can be passed 1148safely through recursive invocations of 1149.Nm . 1150.It Cm \&:R 1151Replaces each word in the variable with everything but its suffix. 1152.It Cm \&:gmtime 1153The value is a format string for 1154.Xr strftime 3 , 1155using the current 1156.Xr gmtime 3 . 1157.It Cm \&:hash 1158Compute a 32bit hash of the value and encode it as hex digits. 1159.It Cm \&:localtime 1160The value is a format string for 1161.Xr strftime 3 , 1162using the current 1163.Xr localtime 3 . 1164.It Cm \&:tA 1165Attempt to convert variable to an absolute path using 1166.Xr realpath 3 , 1167if that fails, the value is unchanged. 1168.It Cm \&:tl 1169Converts variable to lower-case letters. 1170.It Cm \&:ts Ns Ar c 1171Words in the variable are normally separated by a space on expansion. 1172This modifier sets the separator to the character 1173.Ar c . 1174If 1175.Ar c 1176is omitted, then no separator is used. 1177The common escapes (including octal numeric codes), work as expected. 1178.It Cm \&:tu 1179Converts variable to upper-case letters. 1180.It Cm \&:tW 1181Causes the value to be treated as a single word 1182(possibly containing embedded white space). 1183See also 1184.Ql Cm \&:[*] . 1185.It Cm \&:tw 1186Causes the value to be treated as a sequence of 1187words delimited by white space. 1188See also 1189.Ql Cm \&:[@] . 1190.Sm off 1191.It Cm \&:S No \&/ Ar old_string No \&/ Ar new_string No \&/ Op Cm 1gW 1192.Sm on 1193Modify the first occurrence of 1194.Ar old_string 1195in the variable's value, replacing it with 1196.Ar new_string . 1197If a 1198.Ql g 1199is appended to the last slash of the pattern, all occurrences 1200in each word are replaced. 1201If a 1202.Ql 1 1203is appended to the last slash of the pattern, only the first word 1204is affected. 1205If a 1206.Ql W 1207is appended to the last slash of the pattern, 1208then the value is treated as a single word 1209(possibly containing embedded white space). 1210If 1211.Ar old_string 1212begins with a caret 1213.Pq Ql ^ , 1214.Ar old_string 1215is anchored at the beginning of each word. 1216If 1217.Ar old_string 1218ends with a dollar sign 1219.Pq Ql \&$ , 1220it is anchored at the end of each word. 1221Inside 1222.Ar new_string , 1223an ampersand 1224.Pq Ql \*[Am] 1225is replaced by 1226.Ar old_string 1227(without any 1228.Ql ^ 1229or 1230.Ql \&$ ) . 1231Any character may be used as a delimiter for the parts of the modifier 1232string. 1233The anchoring, ampersand and delimiter characters may be escaped with a 1234backslash 1235.Pq Ql \e . 1236.Pp 1237Variable expansion occurs in the normal fashion inside both 1238.Ar old_string 1239and 1240.Ar new_string 1241with the single exception that a backslash is used to prevent the expansion 1242of a dollar sign 1243.Pq Ql \&$ , 1244not a preceding dollar sign as is usual. 1245.Sm off 1246.It Cm \&:C No \&/ Ar pattern No \&/ Ar replacement No \&/ Op Cm 1gW 1247.Sm on 1248The 1249.Cm \&:C 1250modifier is just like the 1251.Cm \&:S 1252modifier except that the old and new strings, instead of being 1253simple strings, are an extended regular expression (see 1254.Xr regex 3 ) 1255string 1256.Ar pattern 1257and an 1258.Xr ed 1 Ns \-style 1259string 1260.Ar replacement . 1261Normally, the first occurrence of the pattern 1262.Ar pattern 1263in each word of the value is substituted with 1264.Ar replacement . 1265The 1266.Ql 1 1267modifier causes the substitution to apply to at most one word; the 1268.Ql g 1269modifier causes the substitution to apply to as many instances of the 1270search pattern 1271.Ar pattern 1272as occur in the word or words it is found in; the 1273.Ql W 1274modifier causes the value to be treated as a single word 1275(possibly containing embedded white space). 1276Note that 1277.Ql 1 1278and 1279.Ql g 1280are orthogonal; the former specifies whether multiple words are 1281potentially affected, the latter whether multiple substitutions can 1282potentially occur within each affected word. 1283.Pp 1284As for the 1285.Cm \&:S 1286modifier, the 1287.Ar pattern 1288and 1289.Ar replacement 1290are subjected to variable expansion before being parsed as 1291regular expressions. 1292.It Cm \&:T 1293Replaces each word in the variable with its last component. 1294.It Cm \&:u 1295Remove adjacent duplicate words (like 1296.Xr uniq 1 ) . 1297.Sm off 1298.It Cm \&:\&? Ar true_string Cm \&: Ar false_string 1299.Sm on 1300If the variable name (not its value), when parsed as a .if conditional 1301expression, evaluates to true, return as its value the 1302.Ar true_string , 1303otherwise return the 1304.Ar false_string . 1305Since the variable name is used as the expression, \&:\&? must be the 1306first modifier after the variable name itself - which will, of course, 1307usually contain variable expansions. 1308A common error is trying to use expressions like 1309.Dl ${NUMBERS:M42:?match:no} 1310which actually tests defined(NUMBERS), 1311to determine is any words match "42" you need to use something like: 1312.Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} . 1313.It Ar :old_string=new_string 1314This is the 1315.At V 1316style variable substitution. 1317It must be the last modifier specified. 1318If 1319.Ar old_string 1320or 1321.Ar new_string 1322do not contain the pattern matching character 1323.Ar % 1324then it is assumed that they are 1325anchored at the end of each word, so only suffixes or entire 1326words may be replaced. 1327Otherwise 1328.Ar % 1329is the substring of 1330.Ar old_string 1331to be replaced in 1332.Ar new_string . 1333.Pp 1334Variable expansion occurs in the normal fashion inside both 1335.Ar old_string 1336and 1337.Ar new_string 1338with the single exception that a backslash is used to prevent the 1339expansion of a dollar sign 1340.Pq Ql \&$ , 1341not a preceding dollar sign as is usual. 1342.Sm off 1343.It Cm \&:@ Ar temp Cm @ Ar string Cm @ 1344.Sm on 1345This is the loop expansion mechanism from the OSF Development 1346Environment (ODE) make. 1347Unlike 1348.Cm \&.for 1349loops expansion occurs at the time of 1350reference. 1351Assign 1352.Ar temp 1353to each word in the variable and evaluate 1354.Ar string . 1355The ODE convention is that 1356.Ar temp 1357should start and end with a period. 1358For example. 1359.Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@} 1360.Pp 1361However a single character variable is often more readable: 1362.Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@} 1363.It Cm \&:U Ns Ar newval 1364If the variable is undefined 1365.Ar newval 1366is the value. 1367If the variable is defined, the existing value is returned. 1368This is another ODE make feature. 1369It is handy for setting per-target CFLAGS for instance: 1370.Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}} 1371If a value is only required if the variable is undefined, use: 1372.Dl ${VAR:D:Unewval} 1373.It Cm \&:D Ns Ar newval 1374If the variable is defined 1375.Ar newval 1376is the value. 1377.It Cm \&:L 1378The name of the variable is the value. 1379.It Cm \&:P 1380The path of the node which has the same name as the variable 1381is the value. 1382If no such node exists or its path is null, then the 1383name of the variable is used. 1384In order for this modifier to work, the name (node) must at least have 1385appeared on the rhs of a dependency. 1386.Sm off 1387.It Cm \&:\&! Ar cmd Cm \&! 1388.Sm on 1389The output of running 1390.Ar cmd 1391is the value. 1392.It Cm \&:sh 1393If the variable is non-empty it is run as a command and the output 1394becomes the new value. 1395.It Cm \&::= Ns Ar str 1396The variable is assigned the value 1397.Ar str 1398after substitution. 1399This modifier and its variations are useful in 1400obscure situations such as wanting to set a variable when shell commands 1401are being parsed. 1402These assignment modifiers always expand to 1403nothing, so if appearing in a rule line by themselves should be 1404preceded with something to keep 1405.Nm 1406happy. 1407.Pp 1408The 1409.Ql Cm \&:: 1410helps avoid false matches with the 1411.At V 1412style 1413.Cm \&:= 1414modifier and since substitution always occurs the 1415.Cm \&::= 1416form is vaguely appropriate. 1417.It Cm \&::?= Ns Ar str 1418As for 1419.Cm \&::= 1420but only if the variable does not already have a value. 1421.It Cm \&::+= Ns Ar str 1422Append 1423.Ar str 1424to the variable. 1425.It Cm \&::!= Ns Ar cmd 1426Assign the output of 1427.Ar cmd 1428to the variable. 1429.It Cm \&:\&[ Ns Ar range Ns Cm \&] 1430Selects one or more words from the value, 1431or performs other operations related to the way in which the 1432value is divided into words. 1433.Pp 1434Ordinarily, a value is treated as a sequence of words 1435delimited by white space. 1436Some modifiers suppress this behaviour, 1437causing a value to be treated as a single word 1438(possibly containing embedded white space). 1439An empty value, or a value that consists entirely of white-space, 1440is treated as a single word. 1441For the purposes of the 1442.Ql Cm \&:[] 1443modifier, the words are indexed both forwards using positive integers 1444(where index 1 represents the first word), 1445and backwards using negative integers 1446(where index \-1 represents the last word). 1447.Pp 1448The 1449.Ar range 1450is subjected to variable expansion, and the expanded result is 1451then interpreted as follows: 1452.Bl -tag -width index 1453.\" :[n] 1454.It Ar index 1455Selects a single word from the value. 1456.\" :[start..end] 1457.It Ar start Ns Cm \&.. Ns Ar end 1458Selects all words from 1459.Ar start 1460to 1461.Ar end , 1462inclusive. 1463For example, 1464.Ql Cm \&:[2..-1] 1465selects all words from the second word to the last word. 1466If 1467.Ar start 1468is greater than 1469.Ar end , 1470then the words are output in reverse order. 1471For example, 1472.Ql Cm \&:[-1..1] 1473selects all the words from last to first. 1474.\" :[*] 1475.It Cm \&* 1476Causes subsequent modifiers to treat the value as a single word 1477(possibly containing embedded white space). 1478Analogous to the effect of 1479\&"$*\&" 1480in Bourne shell. 1481.\" :[0] 1482.It 0 1483Means the same as 1484.Ql Cm \&:[*] . 1485.\" :[*] 1486.It Cm \&@ 1487Causes subsequent modifiers to treat the value as a sequence of words 1488delimited by white space. 1489Analogous to the effect of 1490\&"$@\&" 1491in Bourne shell. 1492.\" :[#] 1493.It Cm \&# 1494Returns the number of words in the value. 1495.El \" :[range] 1496.El 1497.Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS 1498Makefile inclusion, conditional structures and for loops reminiscent 1499of the C programming language are provided in 1500.Nm . 1501All such structures are identified by a line beginning with a single 1502dot 1503.Pq Ql \&. 1504character. 1505Files are included with either 1506.Cm \&.include Aq Ar file 1507or 1508.Cm \&.include Pf \*q Ar file Ns \*q . 1509Variables between the angle brackets or double quotes are expanded 1510to form the file name. 1511If angle brackets are used, the included makefile is expected to be in 1512the system makefile directory. 1513If double quotes are used, the including makefile's directory and any 1514directories specified using the 1515.Fl I 1516option are searched before the system 1517makefile directory. 1518For compatibility with other versions of 1519.Nm 1520.Ql include file ... 1521is also accepted. 1522If the include statement is written as 1523.Cm .-include 1524or as 1525.Cm .sinclude 1526then errors locating and/or opening include files are ignored. 1527.Pp 1528Conditional expressions are also preceded by a single dot as the first 1529character of a line. 1530The possible conditionals are as follows: 1531.Bl -tag -width Ds 1532.It Ic .error Ar message 1533The message is printed along with the name of the makefile and line number, 1534then 1535.Nm 1536will exit. 1537.It Ic .export Ar variable ... 1538Export the specified global variable. 1539If no variable list is provided, all globals are exported 1540except for internal variables (those that start with 1541.Ql \&. ) . 1542This is not affected by the 1543.Fl X 1544flag, so should be used with caution. 1545For compatibility with other 1546.Nm 1547programs 1548.Ql export variable=value 1549is also accepted. 1550.Pp 1551Appending a variable name to 1552.Va .MAKE.EXPORTED 1553is equivalent to exporting a variable. 1554.It Ic .export-env Ar variable ... 1555The same as 1556.Ql .export , 1557except that the variable is not appended to 1558.Va .MAKE.EXPORTED . 1559This allows exporting a value to the environment which is different from that 1560used by 1561.Nm 1562internally. 1563.It Ic .info Ar message 1564The message is printed along with the name of the makefile and line number. 1565.It Ic .undef Ar variable 1566Un-define the specified global variable. 1567Only global variables may be un-defined. 1568.It Ic .unexport Ar variable ... 1569The opposite of 1570.Ql .export . 1571The specified global 1572.Va variable 1573will be removed from 1574.Va .MAKE.EXPORTED . 1575If no variable list is provided, all globals are unexported, 1576and 1577.Va .MAKE.EXPORTED 1578deleted. 1579.It Ic .unexport-env 1580Unexport all globals previously exported and 1581clear the environment inherited from the parent. 1582This operation will cause a memory leak of the original environment, 1583so should be used sparingly. 1584Testing for 1585.Va .MAKE.LEVEL 1586being 0, would make sense. 1587Also note that any variables which originated in the parent environment 1588should be explicitly preserved if desired. 1589For example: 1590.Bd -literal -offset indent 1591.Li .if ${.MAKE.LEVEL} == 0 1592PATH := ${PATH} 1593.Li .unexport-env 1594.Li .export PATH 1595.Li .endif 1596.Pp 1597.Ed 1598Would result in an environment containing only 1599.Ql Ev PATH , 1600which is the minimal useful environment. 1601Actually 1602.Ql Ev .MAKE.LEVEL 1603will also be pushed into the new environment. 1604.It Ic .warning Ar message 1605The message prefixed by 1606.Ql Pa warning: 1607is printed along with the name of the makefile and line number. 1608.It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ... 1609Test the value of an expression. 1610.It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1611Test the value of a variable. 1612.It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1613Test the value of a variable. 1614.It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1615Test the target being built. 1616.It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ... 1617Test the target being built. 1618.It Ic .else 1619Reverse the sense of the last conditional. 1620.It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ... 1621A combination of 1622.Ql Ic .else 1623followed by 1624.Ql Ic .if . 1625.It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1626A combination of 1627.Ql Ic .else 1628followed by 1629.Ql Ic .ifdef . 1630.It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1631A combination of 1632.Ql Ic .else 1633followed by 1634.Ql Ic .ifndef . 1635.It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1636A combination of 1637.Ql Ic .else 1638followed by 1639.Ql Ic .ifmake . 1640.It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1641A combination of 1642.Ql Ic .else 1643followed by 1644.Ql Ic .ifnmake . 1645.It Ic .endif 1646End the body of the conditional. 1647.El 1648.Pp 1649The 1650.Ar operator 1651may be any one of the following: 1652.Bl -tag -width "Cm XX" 1653.It Cm \&|\&| 1654Logical OR. 1655.It Cm \&\*[Am]\*[Am] 1656Logical 1657.Tn AND ; 1658of higher precedence than 1659.Dq \&|\&| . 1660.El 1661.Pp 1662As in C, 1663.Nm 1664will only evaluate a conditional as far as is necessary to determine 1665its value. 1666Parentheses may be used to change the order of evaluation. 1667The boolean operator 1668.Ql Ic \&! 1669may be used to logically negate an entire 1670conditional. 1671It is of higher precedence than 1672.Ql Ic \&\*[Am]\*[Am] . 1673.Pp 1674The value of 1675.Ar expression 1676may be any of the following: 1677.Bl -tag -width defined 1678.It Ic defined 1679Takes a variable name as an argument and evaluates to true if the variable 1680has been defined. 1681.It Ic make 1682Takes a target name as an argument and evaluates to true if the target 1683was specified as part of 1684.Nm Ns 's 1685command line or was declared the default target (either implicitly or 1686explicitly, see 1687.Va .MAIN ) 1688before the line containing the conditional. 1689.It Ic empty 1690Takes a variable, with possible modifiers, and evaluates to true if 1691the expansion of the variable would result in an empty string. 1692.It Ic exists 1693Takes a file name as an argument and evaluates to true if the file exists. 1694The file is searched for on the system search path (see 1695.Va .PATH ) . 1696.It Ic target 1697Takes a target name as an argument and evaluates to true if the target 1698has been defined. 1699.It Ic commands 1700Takes a target name as an argument and evaluates to true if the target 1701has been defined and has commands associated with it. 1702.El 1703.Pp 1704.Ar Expression 1705may also be an arithmetic or string comparison. 1706Variable expansion is 1707performed on both sides of the comparison, after which the integral 1708values are compared. 1709A value is interpreted as hexadecimal if it is 1710preceded by 0x, otherwise it is decimal; octal numbers are not supported. 1711The standard C relational operators are all supported. 1712If after 1713variable expansion, either the left or right hand side of a 1714.Ql Ic == 1715or 1716.Ql Ic "!=" 1717operator is not an integral value, then 1718string comparison is performed between the expanded 1719variables. 1720If no relational operator is given, it is assumed that the expanded 1721variable is being compared against 0 or an empty string in the case 1722of a string comparison. 1723.Pp 1724When 1725.Nm 1726is evaluating one of these conditional expressions, and it encounters 1727a (white-space separated) word it doesn't recognize, either the 1728.Dq make 1729or 1730.Dq defined 1731expression is applied to it, depending on the form of the conditional. 1732If the form is 1733.Ql Ic .ifdef , 1734.Ql Ic .ifndef , 1735or 1736.Ql Ic .if 1737the 1738.Dq defined 1739expression is applied. 1740Similarly, if the form is 1741.Ql Ic .ifmake 1742or 1743.Ql Ic .ifnmake , the 1744.Dq make 1745expression is applied. 1746.Pp 1747If the conditional evaluates to true the parsing of the makefile continues 1748as before. 1749If it evaluates to false, the following lines are skipped. 1750In both cases this continues until a 1751.Ql Ic .else 1752or 1753.Ql Ic .endif 1754is found. 1755.Pp 1756For loops are typically used to apply a set of rules to a list of files. 1757The syntax of a for loop is: 1758.Pp 1759.Bl -tag -compact -width Ds 1760.It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression 1761.It Aq make-rules 1762.It Ic \&.endfor 1763.El 1764.Pp 1765After the for 1766.Ic expression 1767is evaluated, it is split into words. 1768On each iteration of the loop, one word is taken and assigned to each 1769.Ic variable , 1770in order, and these 1771.Ic variables 1772are substituted into the 1773.Ic make-rules 1774inside the body of the for loop. 1775The number of words must come out even; that is, if there are three 1776iteration variables, the number of words provided must be a multiple 1777of three. 1778.Sh COMMENTS 1779Comments begin with a hash 1780.Pq Ql \&# 1781character, anywhere but in a shell 1782command line, and continue to the end of an unescaped new line. 1783.Sh SPECIAL SOURCES (ATTRIBUTES) 1784.Bl -tag -width .IGNOREx 1785.It Ic .EXEC 1786Target is never out of date, but always execute commands anyway. 1787.It Ic .IGNORE 1788Ignore any errors from the commands associated with this target, exactly 1789as if they all were preceded by a dash 1790.Pq Ql \- . 1791.\" .It Ic .INVISIBLE 1792.\" XXX 1793.\" .It Ic .JOIN 1794.\" XXX 1795.It Ic .MADE 1796Mark all sources of this target as being up-to-date. 1797.It Ic .MAKE 1798Execute the commands associated with this target even if the 1799.Fl n 1800or 1801.Fl t 1802options were specified. 1803Normally used to mark recursive 1804.Nm Ns s . 1805.It Ic .META 1806Create a meta file for the target, even if it is flagged as 1807.Ic .PHONY , 1808.Ic .MAKE , 1809or 1810.Ic .SPECIAL . 1811Usage in conjunction with 1812.Ic .MAKE 1813is the most likely case. 1814In "meta" mode, the target is out-of-date if the meta file is missing. 1815.It Ic .NOMETA 1816Do not create a meta file for the target. 1817Meta files are also not created for 1818.Ic .PHONY , 1819.Ic .MAKE , 1820or 1821.Ic .SPECIAL 1822targets. 1823.It Ic .NOMETA_CMP 1824Ignore differences in commands when deciding if target is out of date. 1825This is useful if the command contains a value which always changes. 1826If the number of commands change, though, the target will still be out of date. 1827The same effect applies to any command line that uses the variable 1828.Va .OODATE , 1829which can be used for that purpose even when not otherwise needed or desired: 1830.Bd -literal -offset indent 1831 1832skip-compare-for-some: 1833 @echo this will be compared 1834 @echo this will not ${.OODATE:M.NOMETA_CMP} 1835 @echo this will also be compared 1836 1837.Ed 1838The 1839.Cm \&:M 1840pattern suppresses any expansion of the unwanted variable. 1841.It Ic .NOPATH 1842Do not search for the target in the directories specified by 1843.Ic .PATH . 1844.It Ic .NOTMAIN 1845Normally 1846.Nm 1847selects the first target it encounters as the default target to be built 1848if no target was specified. 1849This source prevents this target from being selected. 1850.It Ic .OPTIONAL 1851If a target is marked with this attribute and 1852.Nm 1853can't figure out how to create it, it will ignore this fact and assume 1854the file isn't needed or already exists. 1855.It Ic .PHONY 1856The target does not 1857correspond to an actual file; it is always considered to be out of date, 1858and will not be created with the 1859.Fl t 1860option. 1861Suffix-transformation rules are not applied to 1862.Ic .PHONY 1863targets. 1864.It Ic .PRECIOUS 1865When 1866.Nm 1867is interrupted, it normally removes any partially made targets. 1868This source prevents the target from being removed. 1869.It Ic .RECURSIVE 1870Synonym for 1871.Ic .MAKE . 1872.It Ic .SILENT 1873Do not echo any of the commands associated with this target, exactly 1874as if they all were preceded by an at sign 1875.Pq Ql @ . 1876.It Ic .USE 1877Turn the target into 1878.Nm Ns 's 1879version of a macro. 1880When the target is used as a source for another target, the other target 1881acquires the commands, sources, and attributes (except for 1882.Ic .USE ) 1883of the 1884source. 1885If the target already has commands, the 1886.Ic .USE 1887target's commands are appended 1888to them. 1889.It Ic .USEBEFORE 1890Exactly like 1891.Ic .USE , 1892but prepend the 1893.Ic .USEBEFORE 1894target commands to the target. 1895.It Ic .WAIT 1896If 1897.Ic .WAIT 1898appears in a dependency line, the sources that precede it are 1899made before the sources that succeed it in the line. 1900Since the dependents of files are not made until the file itself 1901could be made, this also stops the dependents being built unless they 1902are needed for another branch of the dependency tree. 1903So given: 1904.Bd -literal 1905x: a .WAIT b 1906 echo x 1907a: 1908 echo a 1909b: b1 1910 echo b 1911b1: 1912 echo b1 1913 1914.Ed 1915the output is always 1916.Ql a , 1917.Ql b1 , 1918.Ql b , 1919.Ql x . 1920.br 1921The ordering imposed by 1922.Ic .WAIT 1923is only relevant for parallel makes. 1924.El 1925.Sh SPECIAL TARGETS 1926Special targets may not be included with other targets, i.e. they must be 1927the only target specified. 1928.Bl -tag -width .BEGINx 1929.It Ic .BEGIN 1930Any command lines attached to this target are executed before anything 1931else is done. 1932.It Ic .DEFAULT 1933This is sort of a 1934.Ic .USE 1935rule for any target (that was used only as a 1936source) that 1937.Nm 1938can't figure out any other way to create. 1939Only the shell script is used. 1940The 1941.Ic .IMPSRC 1942variable of a target that inherits 1943.Ic .DEFAULT Ns 's 1944commands is set 1945to the target's own name. 1946.It Ic .END 1947Any command lines attached to this target are executed after everything 1948else is done. 1949.It Ic .ERROR 1950Any command lines attached to this target are executed when another target fails. 1951The 1952.Ic .ERROR_TARGET 1953variable is set to the target that failed. 1954See also 1955.Ic MAKE_PRINT_VAR_ON_ERROR . 1956.It Ic .IGNORE 1957Mark each of the sources with the 1958.Ic .IGNORE 1959attribute. 1960If no sources are specified, this is the equivalent of specifying the 1961.Fl i 1962option. 1963.It Ic .INTERRUPT 1964If 1965.Nm 1966is interrupted, the commands for this target will be executed. 1967.It Ic .MAIN 1968If no target is specified when 1969.Nm 1970is invoked, this target will be built. 1971.It Ic .MAKEFLAGS 1972This target provides a way to specify flags for 1973.Nm 1974when the makefile is used. 1975The flags are as if typed to the shell, though the 1976.Fl f 1977option will have 1978no effect. 1979.\" XXX: NOT YET!!!! 1980.\" .It Ic .NOTPARALLEL 1981.\" The named targets are executed in non parallel mode. 1982.\" If no targets are 1983.\" specified, then all targets are executed in non parallel mode. 1984.It Ic .NOPATH 1985Apply the 1986.Ic .NOPATH 1987attribute to any specified sources. 1988.It Ic .NOTPARALLEL 1989Disable parallel mode. 1990.It Ic .NO_PARALLEL 1991Synonym for 1992.Ic .NOTPARALLEL , 1993for compatibility with other pmake variants. 1994.It Ic .ORDER 1995The named targets are made in sequence. 1996This ordering does not add targets to the list of targets to be made. 1997Since the dependents of a target do not get built until the target itself 1998could be built, unless 1999.Ql a 2000is built by another part of the dependency graph, 2001the following is a dependency loop: 2002.Bd -literal 2003\&.ORDER: b a 2004b: a 2005.Ed 2006.Pp 2007The ordering imposed by 2008.Ic .ORDER 2009is only relevant for parallel makes. 2010.\" XXX: NOT YET!!!! 2011.\" .It Ic .PARALLEL 2012.\" The named targets are executed in parallel mode. 2013.\" If no targets are 2014.\" specified, then all targets are executed in parallel mode. 2015.It Ic .PATH 2016The sources are directories which are to be searched for files not 2017found in the current directory. 2018If no sources are specified, any previously specified directories are 2019deleted. 2020If the source is the special 2021.Ic .DOTLAST 2022target, then the current working 2023directory is searched last. 2024.It Ic .PATH. Ns Va suffix 2025Like 2026.Ic .PATH 2027but applies only to files with a particular suffix. 2028The suffix must have been previously declared with 2029.Ic .SUFFIXES . 2030.It Ic .PHONY 2031Apply the 2032.Ic .PHONY 2033attribute to any specified sources. 2034.It Ic .PRECIOUS 2035Apply the 2036.Ic .PRECIOUS 2037attribute to any specified sources. 2038If no sources are specified, the 2039.Ic .PRECIOUS 2040attribute is applied to every 2041target in the file. 2042.It Ic .SHELL 2043Sets the shell that 2044.Nm 2045will use to execute commands. 2046The sources are a set of 2047.Ar field=value 2048pairs. 2049.Bl -tag -width hasErrCtls 2050.It Ar name 2051This is the minimal specification, used to select one of the builtin 2052shell specs; 2053.Ar sh , 2054.Ar ksh , 2055and 2056.Ar csh . 2057.It Ar path 2058Specifies the path to the shell. 2059.It Ar hasErrCtl 2060Indicates whether the shell supports exit on error. 2061.It Ar check 2062The command to turn on error checking. 2063.It Ar ignore 2064The command to disable error checking. 2065.It Ar echo 2066The command to turn on echoing of commands executed. 2067.It Ar quiet 2068The command to turn off echoing of commands executed. 2069.It Ar filter 2070The output to filter after issuing the 2071.Ar quiet 2072command. 2073It is typically identical to 2074.Ar quiet . 2075.It Ar errFlag 2076The flag to pass the shell to enable error checking. 2077.It Ar echoFlag 2078The flag to pass the shell to enable command echoing. 2079.It Ar newline 2080The string literal to pass the shell that results in a single newline 2081character when used outside of any quoting characters. 2082.El 2083Example: 2084.Bd -literal 2085\&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e 2086 check="set \-e" ignore="set +e" \e 2087 echo="set \-v" quiet="set +v" filter="set +v" \e 2088 echoFlag=v errFlag=e newline="'\en'" 2089.Ed 2090.It Ic .SILENT 2091Apply the 2092.Ic .SILENT 2093attribute to any specified sources. 2094If no sources are specified, the 2095.Ic .SILENT 2096attribute is applied to every 2097command in the file. 2098.It Ic .STALE 2099This target gets run when a dependency file contains stale entries, having 2100.Va .ALLSRC 2101set to the name of that dependency file. 2102.It Ic .SUFFIXES 2103Each source specifies a suffix to 2104.Nm . 2105If no sources are specified, any previously specified suffixes are deleted. 2106It allows the creation of suffix-transformation rules. 2107.Pp 2108Example: 2109.Bd -literal 2110\&.SUFFIXES: .o 2111\&.c.o: 2112 cc \-o ${.TARGET} \-c ${.IMPSRC} 2113.Ed 2114.El 2115.Sh ENVIRONMENT 2116.Nm 2117uses the following environment variables, if they exist: 2118.Ev MACHINE , 2119.Ev MACHINE_ARCH , 2120.Ev MAKE , 2121.Ev MAKEFLAGS , 2122.Ev MAKEOBJDIR , 2123.Ev MAKEOBJDIRPREFIX , 2124.Ev MAKESYSPATH , 2125.Ev PWD , 2126and 2127.Ev TMPDIR . 2128.Pp 2129.Ev MAKEOBJDIRPREFIX 2130and 2131.Ev MAKEOBJDIR 2132may only be set in the environment or on the command line to 2133.Nm 2134and not as makefile variables; 2135see the description of 2136.Ql Va .OBJDIR 2137for more details. 2138.Sh FILES 2139.Bl -tag -width /usr/share/mk -compact 2140.It .depend 2141list of dependencies 2142.It Makefile 2143list of dependencies 2144.It makefile 2145list of dependencies 2146.It sys.mk 2147system makefile 2148.It /usr/share/mk 2149system makefile directory 2150.El 2151.Sh COMPATIBILITY 2152The basic make syntax is compatible between different versions of make; 2153however the special variables, variable modifiers and conditionals are not. 2154.Ss Older versions 2155An incomplete list of changes in older versions of 2156.Nm : 2157.Pp 2158The way that .for loop variables are substituted changed after 2159.Nx 5.0 2160so that they still appear to be variable expansions. 2161In particular this stops them being treated as syntax, and removes some 2162obscure problems using them in .if statements. 2163.Pp 2164The way that parallel makes are scheduled changed in 2165.Nx 4.0 2166so that .ORDER and .WAIT apply recursively to the dependent nodes. 2167The algorithms used may change again in the future. 2168.Ss Other make dialects 2169Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not 2170support most of the features of 2171.Nm 2172as described in this manual. 2173Most notably: 2174.Bl -bullet -offset indent 2175.It 2176The 2177.Ic .WAIT 2178and 2179.Ic .ORDER 2180declarations and most functionality pertaining to parallelization. 2181(GNU make supports parallelization but lacks these features needed to 2182control it effectively.) 2183.It 2184Directives, including for loops and conditionals and most of the 2185forms of include files. 2186(GNU make has its own incompatible and less powerful syntax for 2187conditionals.) 2188.It 2189All built-in variables that begin with a dot. 2190.It 2191Most of the special sources and targets that begin with a dot, 2192with the notable exception of 2193.Ic .PHONY , 2194.Ic .PRECIOUS , 2195and 2196.Ic .SUFFIXES . 2197.It 2198Variable modifiers, except for the 2199.Dl :old=new 2200string substitution, which does not portably support globbing with 2201.Ql % 2202and historically only works on declared suffixes. 2203.It 2204The 2205.Ic $> 2206variable even in its short form; most makes support this functionality 2207but its name varies. 2208.El 2209.Pp 2210Some features are somewhat more portable, such as assignment with 2211.Ic += , 2212.Ic ?= , 2213and 2214.Ic != . 2215The 2216.Ic .PATH 2217functionality is based on an older feature 2218.Ic VPATH 2219found in GNU make and many versions of SVR4 make; however, 2220historically its behavior is too ill-defined (and too buggy) to rely 2221upon. 2222.Pp 2223The 2224.Ic $@ 2225and 2226.Ic $< 2227variables are more or less universally portable, as is the 2228.Ic $(MAKE) 2229variable. 2230Basic use of suffix rules (for files only in the current directory, 2231not trying to chain transformations together, etc.) is also reasonably 2232portable. 2233.Sh SEE ALSO 2234.Xr mkdep 1 2235.Sh HISTORY 2236A 2237.Nm 2238command appeared in 2239.At v7 . 2240This 2241.Nm 2242implementation is based on Adam De Boor's pmake program which was written 2243for Sprite at Berkeley. 2244It was designed to be a parallel distributed make running jobs on different 2245machines using a daemon called 2246.Dq customs . 2247.Pp 2248Historically the target/dependency 2249.Dq FRC 2250has been used to FoRCe rebuilding (since the target/dependency 2251does not exist... unless someone creates an 2252.Dq FRC 2253file). 2254.Sh BUGS 2255The 2256.Nm 2257syntax is difficult to parse without actually acting of the data. 2258For instance finding the end of a variable use should involve scanning each 2259the modifiers using the correct terminator for each field. 2260In many places 2261.Nm 2262just counts {} and () in order to find the end of a variable expansion. 2263.Pp 2264There is no way of escaping a space character in a filename. 2265