1.\" $NetBSD: make.1,v 1.222 2013/08/11 09:53:49 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 August 11, 2013 33.Dt MAKE 1 34.Os 35.Sh NAME 36.Nm bmake 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 w 213Print entering and leaving directory messages, pre and post processing. 214.It Ar x 215Run shell commands with 216.Fl x 217so the actual commands are printed as they are executed. 218.El 219.It Fl e 220Specify that environment variables override macro assignments within 221makefiles. 222.It Fl f Ar makefile 223Specify a makefile to read instead of the default 224.Ql Pa makefile . 225If 226.Ar makefile 227is 228.Ql Fl , 229standard input is read. 230Multiple makefiles may be specified, and are read in the order specified. 231.It Fl I Ar directory 232Specify a directory in which to search for makefiles and included makefiles. 233The system makefile directory (or directories, see the 234.Fl m 235option) is automatically included as part of this list. 236.It Fl i 237Ignore non-zero exit of shell commands in the makefile. 238Equivalent to specifying 239.Ql Fl 240before each command line in the makefile. 241.It Fl J Ar private 242This option should 243.Em not 244be specified by the user. 245.Pp 246When the 247.Ar j 248option is in use in a recursive build, this option is passed by a make 249to child makes to allow all the make processes in the build to 250cooperate to avoid overloading the system. 251.It Fl j Ar max_jobs 252Specify the maximum number of jobs that 253.Nm 254may have running at any one time. 255The value is saved in 256.Va .MAKE.JOBS . 257Turns compatibility mode off, unless the 258.Ar B 259flag is also specified. 260When compatibility mode is off, all commands associated with a 261target are executed in a single shell invocation as opposed to the 262traditional one shell invocation per line. 263This can break traditional scripts which change directories on each 264command invocation and then expect to start with a fresh environment 265on the next line. 266It is more efficient to correct the scripts rather than turn backwards 267compatibility on. 268.It Fl k 269Continue processing after errors are encountered, but only on those targets 270that do not depend on the target whose creation caused the error. 271.It Fl m Ar directory 272Specify a directory in which to search for sys.mk and makefiles included 273via the 274.Ao Ar file Ac Ns -style 275include statement. 276The 277.Fl m 278option can be used multiple times to form a search path. 279This path will override the default system include path: /usr/share/mk. 280Furthermore the system include path will be appended to the search path used 281for 282.Qo Ar file Qc Ns -style 283include statements (see the 284.Fl I 285option). 286.Pp 287If a file or directory name in the 288.Fl m 289argument (or the 290.Ev MAKESYSPATH 291environment variable) starts with the string 292.Qq \&.../ 293then 294.Nm 295will search for the specified file or directory named in the remaining part 296of the argument string. 297The search starts with the current directory of 298the Makefile and then works upward towards the root of the filesystem. 299If the search is successful, then the resulting directory replaces the 300.Qq \&.../ 301specification in the 302.Fl m 303argument. 304If used, this feature allows 305.Nm 306to easily search in the current source tree for customized sys.mk files 307(e.g., by using 308.Qq \&.../mk/sys.mk 309as an argument). 310.It Fl n 311Display the commands that would have been executed, but do not 312actually execute them unless the target depends on the .MAKE special 313source (see below). 314.It Fl N 315Display the commands which would have been executed, but do not 316actually execute any of them; useful for debugging top-level makefiles 317without descending into subdirectories. 318.It Fl q 319Do not execute any commands, but exit 0 if the specified targets are 320up-to-date and 1, otherwise. 321.It Fl r 322Do not use the built-in rules specified in the system makefile. 323.It Fl s 324Do not echo any commands as they are executed. 325Equivalent to specifying 326.Ql Ic @ 327before each command line in the makefile. 328.It Fl T Ar tracefile 329When used with the 330.Fl j 331flag, 332append a trace record to 333.Ar tracefile 334for each job started and completed. 335.It Fl t 336Rather than re-building a target as specified in the makefile, create it 337or update its modification time to make it appear up-to-date. 338.It Fl V Ar variable 339Print 340.Nm Ns 's 341idea of the value of 342.Ar variable , 343in the global context. 344Do not build any targets. 345Multiple instances of this option may be specified; 346the variables will be printed one per line, 347with a blank line for each null or undefined variable. 348If 349.Ar variable 350contains a 351.Ql \&$ 352then the value will be expanded before printing. 353.It Fl W 354Treat any warnings during makefile parsing as errors. 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 a series of shell commands, normally 445used to create the target. 446Each of the commands in this script 447.Em must 448be preceded by a tab. 449While any target may appear on a dependency line, only one of these 450dependencies may be followed by a creation script, unless the 451.Ql Ic \&:: 452operator is used. 453.Pp 454If the first characters of the command line are any combination of 455.Ql Ic @ , 456.Ql Ic + , 457or 458.Ql Ic \- , 459the command is treated specially. 460A 461.Ql Ic @ 462causes the command not to be echoed before it is executed. 463A 464.Ql Ic + 465causes the command to be executed even when 466.Fl n 467is given. 468This is similar to the effect of the .MAKE special source, 469except that the effect can be limited to a single line of a script. 470A 471.Ql Ic \- 472causes any non-zero exit status of the command line to be ignored. 473.Pp 474When 475.Nm 476is run in jobs mode with 477.Fl j Ar max_jobs , 478the entire script for the target is fed to a 479single instance of the shell. 480.Pp 481In compatibility (non-jobs) mode, each command is run in a separate process. 482If the command contains any shell meta characters 483.Pq Ql #=|^(){};&<>*?[]:$`\e\en 484it will be passed to the shell, otherwise 485.Nm 486will attempt direct execution. 487.Pp 488Since 489.Nm 490will 491.Xr chdir 2 492to 493.Ql Va .OBJDIR 494before executing any targets, each child process 495starts with that as its current working directory. 496.Pp 497Makefiles should be written so that the mode of 498.Nm 499operation does not change their behavior. 500For example, any command which needs to use 501.Dq cd 502or 503.Dq chdir , 504without side-effect should be put in parenthesis: 505.Bd -literal -offset indent 506 507avoid-chdir-side-effects: 508 @echo Building $@ in `pwd` 509 @(cd ${.CURDIR} && ${.MAKE} $@) 510 @echo Back in `pwd` 511 512ensure-one-shell-regardless-of-mode: 513 @echo Building $@ in `pwd`; \\ 514 (cd ${.CURDIR} && ${.MAKE} $@); \\ 515 echo Back in `pwd` 516.Ed 517.Sh VARIABLE ASSIGNMENTS 518Variables in make are much like variables in the shell, and, by tradition, 519consist of all upper-case letters. 520.Ss Variable assignment modifiers 521The five operators that can be used to assign values to variables are as 522follows: 523.Bl -tag -width Ds 524.It Ic \&= 525Assign the value to the variable. 526Any previous value is overridden. 527.It Ic \&+= 528Append the value to the current value of the variable. 529.It Ic \&?= 530Assign the value to the variable if it is not already defined. 531.It Ic \&:= 532Assign with expansion, i.e. expand the value before assigning it 533to the variable. 534Normally, expansion is not done until the variable is referenced. 535.Em NOTE : 536References to undefined variables are 537.Em not 538expanded. 539This can cause problems when variable modifiers are used. 540.It Ic \&!= 541Expand the value and pass it to the shell for execution and assign 542the result to the variable. 543Any newlines in the result are replaced with spaces. 544.El 545.Pp 546Any white-space before the assigned 547.Ar value 548is removed; if the value is being appended, a single space is inserted 549between the previous contents of the variable and the appended value. 550.Pp 551Variables are expanded by surrounding the variable name with either 552curly braces 553.Pq Ql {} 554or parentheses 555.Pq Ql () 556and preceding it with 557a dollar sign 558.Pq Ql \&$ . 559If the variable name contains only a single letter, the surrounding 560braces or parentheses are not required. 561This shorter form is not recommended. 562.Pp 563If the variable name contains a dollar, then the name itself is expanded first. 564This allows almost arbitrary variable names, however names containing dollar, 565braces, parenthesis, or whitespace are really best avoided! 566.Pp 567If the result of expanding a variable contains a dollar sign 568.Pq Ql \&$ 569the string is expanded again. 570.Pp 571Variable substitution occurs at three distinct times, depending on where 572the variable is being used. 573.Bl -enum 574.It 575Variables in dependency lines are expanded as the line is read. 576.It 577Variables in shell commands are expanded when the shell command is 578executed. 579.It 580.Dq .for 581loop index variables are expanded on each loop iteration. 582Note that other variables are not expanded inside loops so 583the following example code: 584.Bd -literal -offset indent 585 586.Dv .for i in 1 2 3 587a+= ${i} 588j= ${i} 589b+= ${j} 590.Dv .endfor 591 592all: 593 @echo ${a} 594 @echo ${b} 595 596.Ed 597will print: 598.Bd -literal -offset indent 5991 2 3 6003 3 3 601 602.Ed 603Because while ${a} contains 604.Dq 1 2 3 605after the loop is executed, ${b} 606contains 607.Dq ${j} ${j} ${j} 608which expands to 609.Dq 3 3 3 610since after the loop completes ${j} contains 611.Dq 3 . 612.El 613.Ss Variable classes 614The four different classes of variables (in order of increasing precedence) 615are: 616.Bl -tag -width Ds 617.It Environment variables 618Variables defined as part of 619.Nm Ns 's 620environment. 621.It Global variables 622Variables defined in the makefile or in included makefiles. 623.It Command line variables 624Variables defined as part of the command line. 625.It Local variables 626Variables that are defined specific to a certain target. 627The seven local variables are as follows: 628.Bl -tag -width ".ARCHIVE" 629.It Va .ALLSRC 630The list of all sources for this target; also known as 631.Ql Va \&\*[Gt] . 632.It Va .ARCHIVE 633The name of the archive file. 634.It Va .IMPSRC 635In suffix-transformation rules, the name/path of the source from which the 636target is to be transformed (the 637.Dq implied 638source); also known as 639.Ql Va \&\*[Lt] . 640It is not defined in explicit rules. 641.It Va .MEMBER 642The name of the archive member. 643.It Va .OODATE 644The list of sources for this target that were deemed out-of-date; also 645known as 646.Ql Va \&? . 647.It Va .PREFIX 648The file prefix of the target, containing only the file portion, no suffix 649or preceding directory components; also known as 650.Ql Va * . 651.It Va .TARGET 652The name of the target; also known as 653.Ql Va @ . 654.El 655.Pp 656The shorter forms 657.Ql Va @ , 658.Ql Va \&? , 659.Ql Va \&\*[Lt] , 660.Ql Va \&\*[Gt] , 661and 662.Ql Va * 663are permitted for backward 664compatibility with historical makefiles and are not recommended. 665The six variables 666.Ql Va "@F" , 667.Ql Va "@D" , 668.Ql Va "\*[Lt]F" , 669.Ql Va "\*[Lt]D" , 670.Ql Va "*F" , 671and 672.Ql Va "*D" 673are permitted for compatibility with 674.At V 675makefiles and are not recommended. 676.Pp 677Four of the local variables may be used in sources on dependency lines 678because they expand to the proper value for each target on the line. 679These variables are 680.Ql Va .TARGET , 681.Ql Va .PREFIX , 682.Ql Va .ARCHIVE , 683and 684.Ql Va .MEMBER . 685.El 686.Ss Additional built-in variables 687In addition, 688.Nm 689sets or knows about the following variables: 690.Bl -tag -width .MAKEOVERRIDES 691.It Va \&$ 692A single dollar sign 693.Ql \&$ , 694i.e. 695.Ql \&$$ 696expands to a single dollar 697sign. 698.It Va .ALLTARGETS 699The list of all targets encountered in the Makefile. 700If evaluated during 701Makefile parsing, lists only those targets encountered thus far. 702.It Va .CURDIR 703A path to the directory where 704.Nm 705was executed. 706Refer to the description of 707.Ql Ev PWD 708for more details. 709.It Ev MAKE 710The name that 711.Nm 712was executed with 713.Pq Va argv[0] . 714For compatibility 715.Nm 716also sets 717.Va .MAKE 718with the same value. 719The preferred variable to use is the environment variable 720.Ev MAKE 721because it is more compatible with other versions of 722.Nm 723and cannot be confused with the special target with the same name. 724.It Va .MAKE.DEPENDFILE 725Names the makefile (default 726.Ql Pa .depend ) 727from which generated dependencies are read. 728.It Va .MAKE.EXPAND_VARIABLES 729A boolean that controls the default behavior of the 730.Fl V 731option. 732.It Va .MAKE.EXPORTED 733The list of variables exported by 734.Nm . 735.It Va .MAKE.JOBS 736The argument to the 737.Fl j 738option. 739.It Va .MAKE.JOB.PREFIX 740If 741.Nm 742is run with 743.Ar j 744then output for each target is prefixed with a token 745.Ql --- target --- 746the first part of which can be controlled via 747.Va .MAKE.JOB.PREFIX . 748If 749.Va .MAKE.JOB.PREFIX 750is empty, no token is printed. 751.br 752For example: 753.Li .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}] 754would produce tokens like 755.Ql ---make[1234] target --- 756making it easier to track the degree of parallelism being achieved. 757.It Ev MAKEFLAGS 758The environment variable 759.Ql Ev MAKEFLAGS 760may contain anything that 761may be specified on 762.Nm Ns 's 763command line. 764Anything specified on 765.Nm Ns 's 766command line is appended to the 767.Ql Ev MAKEFLAGS 768variable which is then 769entered into the environment for all programs which 770.Nm 771executes. 772.It Va .MAKE.LEVEL 773The recursion depth of 774.Nm . 775The initial instance of 776.Nm 777will be 0, and an incremented value is put into the environment 778to be seen by the next generation. 779This allows tests like: 780.Li .if ${.MAKE.LEVEL} == 0 781to protect things which should only be evaluated in the initial instance of 782.Nm . 783.It Va .MAKE.MAKEFILE_PREFERENCE 784The ordered list of makefile names 785(default 786.Ql Pa makefile , 787.Ql Pa Makefile ) 788that 789.Nm 790will look for. 791.It Va .MAKE.MAKEFILES 792The list of makefiles read by 793.Nm , 794which is useful for tracking dependencies. 795Each makefile is recorded only once, regardless of the number of times read. 796.It Va .MAKE.MODE 797Processed after reading all makefiles. 798Can affect the mode that 799.Nm 800runs in. 801It can contain a number of keywords: 802.Bl -hang -width ignore-cmd 803.It Pa compat 804Like 805.Fl B , 806puts 807.Nm 808into "compat" mode. 809.It Pa meta 810Puts 811.Nm 812into "meta" mode, where meta files are created for each target 813to capture the command run, the output generated and if 814.Xr filemon 4 815is available, the system calls which are of interest to 816.Nm . 817The captured output can be very useful when diagnosing errors. 818.It Pa curdirOk= Ar bf 819Normally 820.Nm 821will not create .meta files in 822.Ql Va .CURDIR . 823This can be overridden by setting 824.Va bf 825to a value which represents True. 826.It Pa env 827For debugging, it can be useful to inlcude the environment 828in the .meta file. 829.It Pa verbose 830If in "meta" mode, print a clue about the target being built. 831This is useful if the build is otherwise running silently. 832The message printed the value of: 833.Va .MAKE.META.PREFIX . 834.It Pa ignore-cmd 835Some makefiles have commands which are simply not stable. 836This keyword causes them to be ignored for 837determining whether a target is out of date in "meta" mode. 838See also 839.Ic .NOMETA_CMP . 840.It Pa silent= Ar bf 841If 842.Va bf 843is True, when a .meta file is created, mark the target 844.Ic .SILENT . 845.El 846.It Va .MAKE.META.BAILIWICK 847In "meta" mode, provides a list of prefixes which 848match the directories controlled by 849.Nm . 850If a file that was generated outside of 851.Va .OBJDIR 852but within said bailiwick is missing, 853the current target is considered out-of-date. 854.It Va .MAKE.META.CREATED 855In "meta" mode, this variable contains a list of all the meta files 856updated. 857If not empty, it can be used to trigger processing of 858.Va .MAKE.META.FILES . 859.It Va .MAKE.META.FILES 860In "meta" mode, this variable contains a list of all the meta files 861used (updated or not). 862This list can be used to process the meta files to extract dependency 863information. 864.It Va .MAKE.META.IGNORE_PATHS 865Provides a list of path prefixes that should be ignored; 866because the contents are expected to change over time. 867The default list includes: 868.Ql Pa /dev /etc /proc /tmp /var/run /var/tmp 869.It Va .MAKE.META.PREFIX 870Defines the message printed for each meta file updated in "meta verbose" mode. 871The default value is: 872.Dl Building ${.TARGET:H:tA}/${.TARGET:T} 873.It Va .MAKEOVERRIDES 874This variable is used to record the names of variables assigned to 875on the command line, so that they may be exported as part of 876.Ql Ev MAKEFLAGS . 877This behaviour can be disabled by assigning an empty value to 878.Ql Va .MAKEOVERRIDES 879within a makefile. 880Extra variables can be exported from a makefile 881by appending their names to 882.Ql Va .MAKEOVERRIDES . 883.Ql Ev MAKEFLAGS 884is re-exported whenever 885.Ql Va .MAKEOVERRIDES 886is modified. 887.It Va .MAKE.PATH_FILEMON 888If 889.Nm 890was built with 891.Xr filemon 4 892support, this is set to the path of the device node. 893This allows makefiles to test for this support. 894.It Va .MAKE.PID 895The process-id of 896.Nm . 897.It Va .MAKE.PPID 898The parent process-id of 899.Nm . 900.It Va .MAKE.BUILT.BY 901The compiler CCVER that built the 902.Dx world. 903.It Va MAKE_PRINT_VAR_ON_ERROR 904When 905.Nm 906stops due to an error, it prints its name and the value of 907.Ql Va .CURDIR 908as well as the value of any variables named in 909.Ql Va MAKE_PRINT_VAR_ON_ERROR . 910.It Va .newline 911This variable is simply assigned a newline character as its value. 912This allows expansions using the 913.Cm \&:@ 914modifier to put a newline between 915iterations of the loop rather than a space. 916For example, the printing of 917.Ql Va MAKE_PRINT_VAR_ON_ERROR 918could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}. 919.It Va .OBJDIR 920A path to the directory where the targets are built. 921Its value is determined by trying to 922.Xr chdir 2 923to the following directories in order and using the first match: 924.Bl -enum 925.It 926.Ev ${MAKEOBJDIRPREFIX}${.CURDIR} 927.Pp 928(Only if 929.Ql Ev MAKEOBJDIRPREFIX 930is set in the environment or on the command line.) 931.It 932.Ev ${MAKEOBJDIR} 933.Pp 934(Only if 935.Ql Ev MAKEOBJDIR 936is set in the environment or on the command line.) 937.It 938.Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE} 939.It 940.Ev ${.CURDIR} Ns Pa /obj 941.It 942.Pa /usr/obj/ Ns Ev ${.CURDIR} 943.It 944.Ev ${.CURDIR} 945.El 946.Pp 947Variable expansion is performed on the value before it's used, 948so expressions such as 949.Dl ${.CURDIR:S,^/usr/src,/var/obj,} 950may be used. 951This is especially useful with 952.Ql Ev MAKEOBJDIR . 953.Pp 954.Ql Va .OBJDIR 955may be modified in the makefile as a global variable. 956In all cases, 957.Nm 958will 959.Xr chdir 2 960to 961.Ql Va .OBJDIR 962and set 963.Ql Ev PWD 964to that directory before executing any targets. 965. 966.It Va .PARSEDIR 967A path to the directory of the current 968.Ql Pa Makefile 969being parsed. 970.It Va .PARSEFILE 971The basename of the current 972.Ql Pa Makefile 973being parsed. 974This variable and 975.Ql Va .PARSEDIR 976are both set only while the 977.Ql Pa Makefiles 978are being parsed. 979If you want to retain their current values, assign them to a variable 980using assignment with expansion: 981.Pq Ql Cm \&:= . 982.It Va .PATH 983A variable that represents the list of directories that 984.Nm 985will search for files. 986The search list should be updated using the target 987.Ql Va .PATH 988rather than the variable. 989.It Ev PWD 990Alternate path to the current directory. 991.Nm 992normally sets 993.Ql Va .CURDIR 994to the canonical path given by 995.Xr getcwd 3 . 996However, if the environment variable 997.Ql Ev PWD 998is set and gives a path to the current directory, then 999.Nm 1000sets 1001.Ql Va .CURDIR 1002to the value of 1003.Ql Ev PWD 1004instead. 1005This behaviour is disabled if 1006.Ql Ev MAKEOBJDIRPREFIX 1007is set or 1008.Ql Ev MAKEOBJDIR 1009contains a variable transform. 1010.Ql Ev PWD 1011is set to the value of 1012.Ql Va .OBJDIR 1013for all programs which 1014.Nm 1015executes. 1016.It Ev .TARGETS 1017The list of targets explicitly specified on the command line, if any. 1018.It Ev VPATH 1019Colon-separated 1020.Pq Dq \&: 1021lists of directories that 1022.Nm 1023will search for files. 1024The variable is supported for compatibility with old make programs only, 1025use 1026.Ql Va .PATH 1027instead. 1028.El 1029.Ss Variable modifiers 1030Variable expansion may be modified to select or modify each word of the 1031variable (where a 1032.Dq word 1033is white-space delimited sequence of characters). 1034The general format of a variable expansion is as follows: 1035.Pp 1036.Dl ${variable[:modifier[:...]]} 1037.Pp 1038Each modifier begins with a colon, 1039which may be escaped with a backslash 1040.Pq Ql \e . 1041.Pp 1042A set of modifiers can be specified via a variable, as follows: 1043.Pp 1044.Dl modifier_variable=modifier[:...] 1045.Dl ${variable:${modifier_variable}[:...]} 1046.Pp 1047In this case the first modifier in the modifier_variable does not 1048start with a colon, since that must appear in the referencing 1049variable. 1050If any of the modifiers in the modifier_variable contain a dollar sign 1051.Pq Ql $ , 1052these must be doubled to avoid early expansion. 1053.Pp 1054The supported modifiers are: 1055.Bl -tag -width EEE 1056.It Cm \&:E 1057Replaces each word in the variable with its suffix. 1058.It Cm \&:H 1059Replaces each word in the variable with everything but the last component. 1060.It Cm \&:M Ns Ar pattern 1061Select only those words that match 1062.Ar pattern . 1063The standard shell wildcard characters 1064.Pf ( Ql * , 1065.Ql \&? , 1066and 1067.Ql Oo Oc ) 1068may 1069be used. 1070The wildcard characters may be escaped with a backslash 1071.Pq Ql \e . 1072.It Cm \&:N Ns Ar pattern 1073This is identical to 1074.Ql Cm \&:M , 1075but selects all words which do not match 1076.Ar pattern . 1077.It Cm \&:O 1078Order every word in variable alphabetically. 1079To sort words in 1080reverse order use the 1081.Ql Cm \&:O:[-1..1] 1082combination of modifiers. 1083.It Cm \&:Ox 1084Randomize words in variable. 1085The results will be different each time you are referring to the 1086modified variable; use the assignment with expansion 1087.Pq Ql Cm \&:= 1088to prevent such behaviour. 1089For example, 1090.Bd -literal -offset indent 1091LIST= uno due tre quattro 1092RANDOM_LIST= ${LIST:Ox} 1093STATIC_RANDOM_LIST:= ${LIST:Ox} 1094 1095all: 1096 @echo "${RANDOM_LIST}" 1097 @echo "${RANDOM_LIST}" 1098 @echo "${STATIC_RANDOM_LIST}" 1099 @echo "${STATIC_RANDOM_LIST}" 1100.Ed 1101may produce output similar to: 1102.Bd -literal -offset indent 1103quattro due tre uno 1104tre due quattro uno 1105due uno quattro tre 1106due uno quattro tre 1107.Ed 1108.It Cm \&:Q 1109Quotes every shell meta-character in the variable, so that it can be passed 1110safely through recursive invocations of 1111.Nm . 1112.It Cm \&:R 1113Replaces each word in the variable with everything but its suffix. 1114.It Cm \&:gmtime 1115The value is a format string for 1116.Xr strftime 3 , 1117using the current 1118.Xr gmtime 3 . 1119.It Cm \&:hash 1120Compute a 32bit hash of the value and encode it as hex digits. 1121.It Cm \&:localtime 1122The value is a format string for 1123.Xr strftime 3 , 1124using the current 1125.Xr localtime 3 . 1126.It Cm \&:tA 1127Attempt to convert variable to an absolute path using 1128.Xr realpath 3 , 1129if that fails, the value is unchanged. 1130.It Cm \&:tl 1131Converts variable to lower-case letters. 1132.It Cm \&:ts Ns Ar c 1133Words in the variable are normally separated by a space on expansion. 1134This modifier sets the separator to the character 1135.Ar c . 1136If 1137.Ar c 1138is omitted, then no separator is used. 1139The common escapes (including octal numeric codes), work as expected. 1140.It Cm \&:tu 1141Converts variable to upper-case letters. 1142.It Cm \&:tW 1143Causes the value to be treated as a single word 1144(possibly containing embedded white space). 1145See also 1146.Ql Cm \&:[*] . 1147.It Cm \&:tw 1148Causes the value to be treated as a sequence of 1149words delimited by white space. 1150See also 1151.Ql Cm \&:[@] . 1152.Sm off 1153.It Cm \&:S No \&/ Ar old_string No \&/ Ar new_string No \&/ Op Cm 1gW 1154.Sm on 1155Modify the first occurrence of 1156.Ar old_string 1157in the variable's value, replacing it with 1158.Ar new_string . 1159If a 1160.Ql g 1161is appended to the last slash of the pattern, all occurrences 1162in each word are replaced. 1163If a 1164.Ql 1 1165is appended to the last slash of the pattern, only the first word 1166is affected. 1167If a 1168.Ql W 1169is appended to the last slash of the pattern, 1170then the value is treated as a single word 1171(possibly containing embedded white space). 1172If 1173.Ar old_string 1174begins with a caret 1175.Pq Ql ^ , 1176.Ar old_string 1177is anchored at the beginning of each word. 1178If 1179.Ar old_string 1180ends with a dollar sign 1181.Pq Ql \&$ , 1182it is anchored at the end of each word. 1183Inside 1184.Ar new_string , 1185an ampersand 1186.Pq Ql \*[Am] 1187is replaced by 1188.Ar old_string 1189(without any 1190.Ql ^ 1191or 1192.Ql \&$ ) . 1193Any character may be used as a delimiter for the parts of the modifier 1194string. 1195The anchoring, ampersand and delimiter characters may be escaped with a 1196backslash 1197.Pq Ql \e . 1198.Pp 1199Variable expansion occurs in the normal fashion inside both 1200.Ar old_string 1201and 1202.Ar new_string 1203with the single exception that a backslash is used to prevent the expansion 1204of a dollar sign 1205.Pq Ql \&$ , 1206not a preceding dollar sign as is usual. 1207.Sm off 1208.It Cm \&:C No \&/ Ar pattern No \&/ Ar replacement No \&/ Op Cm 1gW 1209.Sm on 1210The 1211.Cm \&:C 1212modifier is just like the 1213.Cm \&:S 1214modifier except that the old and new strings, instead of being 1215simple strings, are a regular expression (see 1216.Xr regex 3 ) 1217string 1218.Ar pattern 1219and an 1220.Xr ed 1 Ns \-style 1221string 1222.Ar replacement . 1223Normally, the first occurrence of the pattern 1224.Ar pattern 1225in each word of the value is substituted with 1226.Ar replacement . 1227The 1228.Ql 1 1229modifier causes the substitution to apply to at most one word; the 1230.Ql g 1231modifier causes the substitution to apply to as many instances of the 1232search pattern 1233.Ar pattern 1234as occur in the word or words it is found in; the 1235.Ql W 1236modifier causes the value to be treated as a single word 1237(possibly containing embedded white space). 1238Note that 1239.Ql 1 1240and 1241.Ql g 1242are orthogonal; the former specifies whether multiple words are 1243potentially affected, the latter whether multiple substitutions can 1244potentially occur within each affected word. 1245.It Cm \&:T 1246Replaces each word in the variable with its last component. 1247.It Cm \&:u 1248Remove adjacent duplicate words (like 1249.Xr uniq 1 ) . 1250.Sm off 1251.It Cm \&:\&? Ar true_string Cm \&: Ar false_string 1252.Sm on 1253If the variable name (not its value), when parsed as a .if conditional 1254expression, evaluates to true, return as its value the 1255.Ar true_string , 1256otherwise return the 1257.Ar false_string . 1258Since the variable name is used as the expression, \&:\&? must be the 1259first modifier after the variable name itself - which will, of course, 1260usually contain variable expansions. 1261A common error is trying to use expressions like 1262.Dl ${NUMBERS:M42:?match:no} 1263which actually tests defined(NUMBERS), 1264to determine is any words match "42" you need to use something like: 1265.Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} . 1266.It Ar :old_string=new_string 1267This is the 1268.At V 1269style variable substitution. 1270It must be the last modifier specified. 1271If 1272.Ar old_string 1273or 1274.Ar new_string 1275do not contain the pattern matching character 1276.Ar % 1277then it is assumed that they are 1278anchored at the end of each word, so only suffixes or entire 1279words may be replaced. 1280Otherwise 1281.Ar % 1282is the substring of 1283.Ar old_string 1284to be replaced in 1285.Ar new_string . 1286.Pp 1287Variable expansion occurs in the normal fashion inside both 1288.Ar old_string 1289and 1290.Ar new_string 1291with the single exception that a backslash is used to prevent the 1292expansion of a dollar sign 1293.Pq Ql \&$ , 1294not a preceding dollar sign as is usual. 1295.Sm off 1296.It Cm \&:@ Ar temp Cm @ Ar string Cm @ 1297.Sm on 1298This is the loop expansion mechanism from the OSF Development 1299Environment (ODE) make. 1300Unlike 1301.Cm \&.for 1302loops expansion occurs at the time of 1303reference. 1304Assign 1305.Ar temp 1306to each word in the variable and evaluate 1307.Ar string . 1308The ODE convention is that 1309.Ar temp 1310should start and end with a period. 1311For example. 1312.Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@} 1313.Pp 1314However a single character variable is often more readable: 1315.Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@} 1316.It Cm \&:U Ns Ar newval 1317If the variable is undefined 1318.Ar newval 1319is the value. 1320If the variable is defined, the existing value is returned. 1321This is another ODE make feature. 1322It is handy for setting per-target CFLAGS for instance: 1323.Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}} 1324If a value is only required if the variable is undefined, use: 1325.Dl ${VAR:D:Unewval} 1326.It Cm \&:D Ns Ar newval 1327If the variable is defined 1328.Ar newval 1329is the value. 1330.It Cm \&:L 1331The name of the variable is the value. 1332.It Cm \&:P 1333The path of the node which has the same name as the variable 1334is the value. 1335If no such node exists or its path is null, then the 1336name of the variable is used. 1337In order for this modifier to work, the name (node) must at least have 1338appeared on the rhs of a dependency. 1339.Sm off 1340.It Cm \&:\&! Ar cmd Cm \&! 1341.Sm on 1342The output of running 1343.Ar cmd 1344is the value. 1345.It Cm \&:sh 1346If the variable is non-empty it is run as a command and the output 1347becomes the new value. 1348.It Cm \&::= Ns Ar str 1349The variable is assigned the value 1350.Ar str 1351after substitution. 1352This modifier and its variations are useful in 1353obscure situations such as wanting to set a variable when shell commands 1354are being parsed. 1355These assignment modifiers always expand to 1356nothing, so if appearing in a rule line by themselves should be 1357preceded with something to keep 1358.Nm 1359happy. 1360.Pp 1361The 1362.Ql Cm \&:: 1363helps avoid false matches with the 1364.At V 1365style 1366.Cm \&:= 1367modifier and since substitution always occurs the 1368.Cm \&::= 1369form is vaguely appropriate. 1370.It Cm \&::?= Ns Ar str 1371As for 1372.Cm \&::= 1373but only if the variable does not already have a value. 1374.It Cm \&::+= Ns Ar str 1375Append 1376.Ar str 1377to the variable. 1378.It Cm \&::!= Ns Ar cmd 1379Assign the output of 1380.Ar cmd 1381to the variable. 1382.It Cm \&:\&[ Ns Ar range Ns Cm \&] 1383Selects one or more words from the value, 1384or performs other operations related to the way in which the 1385value is divided into words. 1386.Pp 1387Ordinarily, a value is treated as a sequence of words 1388delimited by white space. 1389Some modifiers suppress this behaviour, 1390causing a value to be treated as a single word 1391(possibly containing embedded white space). 1392An empty value, or a value that consists entirely of white-space, 1393is treated as a single word. 1394For the purposes of the 1395.Ql Cm \&:[] 1396modifier, the words are indexed both forwards using positive integers 1397(where index 1 represents the first word), 1398and backwards using negative integers 1399(where index \-1 represents the last word). 1400.Pp 1401The 1402.Ar range 1403is subjected to variable expansion, and the expanded result is 1404then interpreted as follows: 1405.Bl -tag -width index 1406.\" :[n] 1407.It Ar index 1408Selects a single word from the value. 1409.\" :[start..end] 1410.It Ar start Ns Cm \&.. Ns Ar end 1411Selects all words from 1412.Ar start 1413to 1414.Ar end , 1415inclusive. 1416For example, 1417.Ql Cm \&:[2..-1] 1418selects all words from the second word to the last word. 1419If 1420.Ar start 1421is greater than 1422.Ar end , 1423then the words are output in reverse order. 1424For example, 1425.Ql Cm \&:[-1..1] 1426selects all the words from last to first. 1427.\" :[*] 1428.It Cm \&* 1429Causes subsequent modifiers to treat the value as a single word 1430(possibly containing embedded white space). 1431Analogous to the effect of 1432\&"$*\&" 1433in Bourne shell. 1434.\" :[0] 1435.It 0 1436Means the same as 1437.Ql Cm \&:[*] . 1438.\" :[*] 1439.It Cm \&@ 1440Causes subsequent modifiers to treat the value as a sequence of words 1441delimited by white space. 1442Analogous to the effect of 1443\&"$@\&" 1444in Bourne shell. 1445.\" :[#] 1446.It Cm \&# 1447Returns the number of words in the value. 1448.El \" :[range] 1449.El 1450.Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS 1451Makefile inclusion, conditional structures and for loops reminiscent 1452of the C programming language are provided in 1453.Nm . 1454All such structures are identified by a line beginning with a single 1455dot 1456.Pq Ql \&. 1457character. 1458Files are included with either 1459.Cm \&.include Aq Ar file 1460or 1461.Cm \&.include Pf \*q Ar file Ns \*q . 1462Variables between the angle brackets or double quotes are expanded 1463to form the file name. 1464If angle brackets are used, the included makefile is expected to be in 1465the system makefile directory. 1466If double quotes are used, the including makefile's directory and any 1467directories specified using the 1468.Fl I 1469option are searched before the system 1470makefile directory. 1471For compatibility with other versions of 1472.Nm 1473.Ql include file ... 1474is also accepted. 1475If the include statement is written as 1476.Cm .-include 1477or as 1478.Cm .sinclude 1479then errors locating and/or opening include files are ignored. 1480.Pp 1481Conditional expressions are also preceded by a single dot as the first 1482character of a line. 1483The possible conditionals are as follows: 1484.Bl -tag -width Ds 1485.It Ic .error Ar message 1486The message is printed along with the name of the makefile and line number, 1487then 1488.Nm 1489will exit. 1490.It Ic .export Ar variable ... 1491Export the specified global variable. 1492If no variable list is provided, all globals are exported 1493except for internal variables (those that start with 1494.Ql \&. ) . 1495This is not affected by the 1496.Fl X 1497flag, so should be used with caution. 1498For compatibility with other 1499.Nm 1500programs 1501.Ql export variable=value 1502is also accepted. 1503.Pp 1504Appending a variable name to 1505.Va .MAKE.EXPORTED 1506is equivalent to exporting a variable. 1507.It Ic .export-env Ar variable ... 1508The same as 1509.Ql .export , 1510except that the variable is not appended to 1511.Va .MAKE.EXPORTED . 1512This allows exporting a value to the environment which is different from that 1513used by 1514.Nm 1515internally. 1516.It Ic .info Ar message 1517The message is printed along with the name of the makefile and line number. 1518.It Ic .undef Ar variable 1519Un-define the specified global variable. 1520Only global variables may be un-defined. 1521.It Ic .unexport Ar variable ... 1522The opposite of 1523.Ql .export . 1524The specified global 1525.Va variable 1526will be removed from 1527.Va .MAKE.EXPORTED . 1528If no variable list is provided, all globals are unexported, 1529and 1530.Va .MAKE.EXPORTED 1531deleted. 1532.It Ic .unexport-env 1533Unexport all globals previously exported and 1534clear the environment inherited from the parent. 1535This operation will cause a memory leak of the original environment, 1536so should be used sparingly. 1537Testing for 1538.Va .MAKE.LEVEL 1539being 0, would make sense. 1540Also note that any variables which originated in the parent environment 1541should be explicitly preserved if desired. 1542For example: 1543.Bd -literal -offset indent 1544.Li .if ${.MAKE.LEVEL} == 0 1545PATH := ${PATH} 1546.Li .unexport-env 1547.Li .export PATH 1548.Li .endif 1549.Ed 1550.Pp 1551Would result in an environment containing only 1552.Ql Ev PATH , 1553which is the minimal useful environment. 1554Actually 1555.Ql Ev .MAKE.LEVEL 1556will also be pushed into the new environment. 1557.It Ic .warning Ar message 1558The message prefixed by 1559.Ql Pa warning: 1560is printed along with the name of the makefile and line number. 1561.It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ... 1562Test the value of an expression. 1563.It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1564Test the value of a variable. 1565.It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1566Test the value of a variable. 1567.It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1568Test the target being built. 1569.It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ... 1570Test the target being built. 1571.It Ic .else 1572Reverse the sense of the last conditional. 1573.It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ... 1574A combination of 1575.Ql Ic .else 1576followed by 1577.Ql Ic .if . 1578.It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1579A combination of 1580.Ql Ic .else 1581followed by 1582.Ql Ic .ifdef . 1583.It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1584A combination of 1585.Ql Ic .else 1586followed by 1587.Ql Ic .ifndef . 1588.It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1589A combination of 1590.Ql Ic .else 1591followed by 1592.Ql Ic .ifmake . 1593.It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1594A combination of 1595.Ql Ic .else 1596followed by 1597.Ql Ic .ifnmake . 1598.It Ic .endif 1599End the body of the conditional. 1600.El 1601.Pp 1602The 1603.Ar operator 1604may be any one of the following: 1605.Bl -tag -width "Cm XX" 1606.It Cm \&|\&| 1607Logical OR. 1608.It Cm \&\*[Am]\*[Am] 1609Logical 1610.Tn AND ; 1611of higher precedence than 1612.Dq \&|\&| . 1613.El 1614.Pp 1615As in C, 1616.Nm 1617will only evaluate a conditional as far as is necessary to determine 1618its value. 1619Parentheses may be used to change the order of evaluation. 1620The boolean operator 1621.Ql Ic \&! 1622may be used to logically negate an entire 1623conditional. 1624It is of higher precedence than 1625.Ql Ic \&\*[Am]\*[Am] . 1626.Pp 1627The value of 1628.Ar expression 1629may be any of the following: 1630.Bl -tag -width defined 1631.It Ic defined 1632Takes a variable name as an argument and evaluates to true if the variable 1633has been defined. 1634.It Ic make 1635Takes a target name as an argument and evaluates to true if the target 1636was specified as part of 1637.Nm Ns 's 1638command line or was declared the default target (either implicitly or 1639explicitly, see 1640.Va .MAIN ) 1641before the line containing the conditional. 1642.It Ic empty 1643Takes a variable, with possible modifiers, and evaluates to true if 1644the expansion of the variable would result in an empty string. 1645.It Ic exists 1646Takes a file name as an argument and evaluates to true if the file exists. 1647The file is searched for on the system search path (see 1648.Va .PATH ) . 1649.It Ic target 1650Takes a target name as an argument and evaluates to true if the target 1651has been defined. 1652.It Ic commands 1653Takes a target name as an argument and evaluates to true if the target 1654has been defined and has commands associated with it. 1655.El 1656.Pp 1657.Ar Expression 1658may also be an arithmetic or string comparison. 1659Variable expansion is 1660performed on both sides of the comparison, after which the integral 1661values are compared. 1662A value is interpreted as hexadecimal if it is 1663preceded by 0x, otherwise it is decimal; octal numbers are not supported. 1664The standard C relational operators are all supported. 1665If after 1666variable expansion, either the left or right hand side of a 1667.Ql Ic == 1668or 1669.Ql Ic "!=" 1670operator is not an integral value, then 1671string comparison is performed between the expanded 1672variables. 1673If no relational operator is given, it is assumed that the expanded 1674variable is being compared against 0 or an empty string in the case 1675of a string comparison. 1676.Pp 1677When 1678.Nm 1679is evaluating one of these conditional expressions, and it encounters 1680a (white-space separated) word it doesn't recognize, either the 1681.Dq make 1682or 1683.Dq defined 1684expression is applied to it, depending on the form of the conditional. 1685If the form is 1686.Ql Ic .ifdef , 1687.Ql Ic .ifndef , 1688or 1689.Ql Ic .if 1690the 1691.Dq defined 1692expression is applied. 1693Similarly, if the form is 1694.Ql Ic .ifmake 1695or 1696.Ql Ic .ifnmake , the 1697.Dq make 1698expression is applied. 1699.Pp 1700If the conditional evaluates to true the parsing of the makefile continues 1701as before. 1702If it evaluates to false, the following lines are skipped. 1703In both cases this continues until a 1704.Ql Ic .else 1705or 1706.Ql Ic .endif 1707is found. 1708.Pp 1709For loops are typically used to apply a set of rules to a list of files. 1710The syntax of a for loop is: 1711.Pp 1712.Bl -tag -compact -width Ds 1713.It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression 1714.It Aq make-rules 1715.It Ic \&.endfor 1716.El 1717.Pp 1718After the for 1719.Ic expression 1720is evaluated, it is split into words. 1721On each iteration of the loop, one word is taken and assigned to each 1722.Ic variable , 1723in order, and these 1724.Ic variables 1725are substituted into the 1726.Ic make-rules 1727inside the body of the for loop. 1728The number of words must come out even; that is, if there are three 1729iteration variables, the number of words provided must be a multiple 1730of three. 1731.Sh COMMENTS 1732Comments begin with a hash 1733.Pq Ql \&# 1734character, anywhere but in a shell 1735command line, and continue to the end of an unescaped new line. 1736.Sh SPECIAL SOURCES (ATTRIBUTES) 1737.Bl -tag -width .IGNOREx 1738.It Ic .EXEC 1739Target is never out of date, but always execute commands anyway. 1740.It Ic .IGNORE 1741Ignore any errors from the commands associated with this target, exactly 1742as if they all were preceded by a dash 1743.Pq Ql \- . 1744.\" .It Ic .INVISIBLE 1745.\" XXX 1746.\" .It Ic .JOIN 1747.\" XXX 1748.It Ic .MADE 1749Mark all sources of this target as being up-to-date. 1750.It Ic .MAKE 1751Execute the commands associated with this target even if the 1752.Fl n 1753or 1754.Fl t 1755options were specified. 1756Normally used to mark recursive 1757.Nm Ns 's . 1758.It Ic .META 1759Create a meta file for the target, even if it is flagged as 1760.Ic .PHONY , 1761.Ic .MAKE , 1762or 1763.Ic .SPECIAL . 1764Usage in conjunction with 1765.Ic .MAKE 1766is the most likely case. 1767In "meta" mode, the target is out-of-date if the meta file is missing. 1768.It Ic .NOMETA 1769Do not create a meta file for the target. 1770Meta files are also not created for 1771.Ic .PHONY , 1772.Ic .MAKE , 1773or 1774.Ic .SPECIAL 1775targets. 1776.It Ic .NOMETA_CMP 1777Ignore differences in commands when deciding if target is out of date. 1778This is useful if the command contains a value which always changes. 1779If the number of commands change, though, the target will still be out of date. 1780The same effect applies to any command line that uses the variable 1781.Va .OODATE , 1782which can be used for that purpose even when not otherwise needed or desired: 1783.Bd -literal -offset indent 1784 1785skip-compare-for-some: 1786 @echo this will be compared 1787 @echo this will not ${.OODATE:M.NOMETA_CMP} 1788 @echo this will also be compared 1789 1790.Ed 1791The 1792.Cm \&:M 1793pattern suppresses any expansion of the unwanted variable. 1794.It Ic .NOPATH 1795Do not search for the target in the directories specified by 1796.Ic .PATH . 1797.It Ic .NOTMAIN 1798Normally 1799.Nm 1800selects the first target it encounters as the default target to be built 1801if no target was specified. 1802This source prevents this target from being selected. 1803.It Ic .OPTIONAL 1804If a target is marked with this attribute and 1805.Nm 1806can't figure out how to create it, it will ignore this fact and assume 1807the file isn't needed or already exists. 1808.It Ic .PHONY 1809The target does not 1810correspond to an actual file; it is always considered to be out of date, 1811and will not be created with the 1812.Fl t 1813option. 1814Suffix-transformation rules are not applied to 1815.Ic .PHONY 1816targets. 1817.It Ic .PRECIOUS 1818When 1819.Nm 1820is interrupted, it normally removes any partially made targets. 1821This source prevents the target from being removed. 1822.It Ic .RECURSIVE 1823Synonym for 1824.Ic .MAKE . 1825.It Ic .SILENT 1826Do not echo any of the commands associated with this target, exactly 1827as if they all were preceded by an at sign 1828.Pq Ql @ . 1829.It Ic .USE 1830Turn the target into 1831.Nm Ns 's 1832version of a macro. 1833When the target is used as a source for another target, the other target 1834acquires the commands, sources, and attributes (except for 1835.Ic .USE ) 1836of the 1837source. 1838If the target already has commands, the 1839.Ic .USE 1840target's commands are appended 1841to them. 1842.It Ic .USEBEFORE 1843Exactly like 1844.Ic .USE , 1845but prepend the 1846.Ic .USEBEFORE 1847target commands to the target. 1848.It Ic .WAIT 1849If 1850.Ic .WAIT 1851appears in a dependency line, the sources that precede it are 1852made before the sources that succeed it in the line. 1853Since the dependents of files are not made until the file itself 1854could be made, this also stops the dependents being built unless they 1855are needed for another branch of the dependency tree. 1856So given: 1857.Bd -literal 1858x: a .WAIT b 1859 echo x 1860a: 1861 echo a 1862b: b1 1863 echo b 1864b1: 1865 echo b1 1866 1867.Ed 1868the output is always 1869.Ql a , 1870.Ql b1 , 1871.Ql b , 1872.Ql x . 1873.br 1874The ordering imposed by 1875.Ic .WAIT 1876is only relevant for parallel makes. 1877.El 1878.Sh SPECIAL TARGETS 1879Special targets may not be included with other targets, i.e. they must be 1880the only target specified. 1881.Bl -tag -width .BEGINx 1882.It Ic .BEGIN 1883Any command lines attached to this target are executed before anything 1884else is done. 1885.It Ic .DEFAULT 1886This is sort of a 1887.Ic .USE 1888rule for any target (that was used only as a 1889source) that 1890.Nm 1891can't figure out any other way to create. 1892Only the shell script is used. 1893The 1894.Ic .IMPSRC 1895variable of a target that inherits 1896.Ic .DEFAULT Ns 's 1897commands is set 1898to the target's own name. 1899.It Ic .END 1900Any command lines attached to this target are executed after everything 1901else is done. 1902.It Ic .ERROR 1903Any command lines attached to this target are executed when another target fails. 1904The 1905.Ic .ERROR_TARGET 1906variable is set to the target that failed. 1907See also 1908.Ic MAKE_PRINT_VAR_ON_ERROR . 1909.It Ic .IGNORE 1910Mark each of the sources with the 1911.Ic .IGNORE 1912attribute. 1913If no sources are specified, this is the equivalent of specifying the 1914.Fl i 1915option. 1916.It Ic .INTERRUPT 1917If 1918.Nm 1919is interrupted, the commands for this target will be executed. 1920.It Ic .MAIN 1921If no target is specified when 1922.Nm 1923is invoked, this target will be built. 1924.It Ic .MAKEFLAGS 1925This target provides a way to specify flags for 1926.Nm 1927when the makefile is used. 1928The flags are as if typed to the shell, though the 1929.Fl f 1930option will have 1931no effect. 1932.\" XXX: NOT YET!!!! 1933.\" .It Ic .NOTPARALLEL 1934.\" The named targets are executed in non parallel mode. 1935.\" If no targets are 1936.\" specified, then all targets are executed in non parallel mode. 1937.It Ic .NOPATH 1938Apply the 1939.Ic .NOPATH 1940attribute to any specified sources. 1941.It Ic .NOTPARALLEL 1942Disable parallel mode. 1943.It Ic .NO_PARALLEL 1944Synonym for 1945.Ic .NOTPARALLEL , 1946for compatibility with other pmake variants. 1947.It Ic .ORDER 1948The named targets are made in sequence. 1949This ordering does not add targets to the list of targets to be made. 1950Since the dependents of a target do not get built until the target itself 1951could be built, unless 1952.Ql a 1953is built by another part of the dependency graph, 1954the following is a dependency loop: 1955.Bd -literal 1956\&.ORDER: b a 1957b: a 1958.Ed 1959.Pp 1960The ordering imposed by 1961.Ic .ORDER 1962is only relevant for parallel makes. 1963.\" XXX: NOT YET!!!! 1964.\" .It Ic .PARALLEL 1965.\" The named targets are executed in parallel mode. 1966.\" If no targets are 1967.\" specified, then all targets are executed in parallel mode. 1968.It Ic .PATH 1969The sources are directories which are to be searched for files not 1970found in the current directory. 1971If no sources are specified, any previously specified directories are 1972deleted. 1973If the source is the special 1974.Ic .DOTLAST 1975target, then the current working 1976directory is searched last. 1977.It Ic .PATH. Ns Va suffix 1978Like 1979.Ic .PATH 1980but applies only to files with a particular suffix. 1981The suffix must have been previously declared with 1982.Ic .SUFFIXES . 1983.It Ic .PHONY 1984Apply the 1985.Ic .PHONY 1986attribute to any specified sources. 1987.It Ic .PRECIOUS 1988Apply the 1989.Ic .PRECIOUS 1990attribute to any specified sources. 1991If no sources are specified, the 1992.Ic .PRECIOUS 1993attribute is applied to every 1994target in the file. 1995.It Ic .SHELL 1996Sets the shell that 1997.Nm 1998will use to execute commands. 1999The sources are a set of 2000.Ar field=value 2001pairs. 2002.Bl -tag -width hasErrCtls 2003.It Ar name 2004This is the minimal specification, used to select one of the builtin 2005shell specs; 2006.Ar sh , 2007.Ar ksh , 2008and 2009.Ar csh . 2010.It Ar path 2011Specifies the path to the shell. 2012.It Ar hasErrCtl 2013Indicates whether the shell supports exit on error. 2014.It Ar check 2015The command to turn on error checking. 2016.It Ar ignore 2017The command to disable error checking. 2018.It Ar echo 2019The command to turn on echoing of commands executed. 2020.It Ar quiet 2021The command to turn off echoing of commands executed. 2022.It Ar filter 2023The output to filter after issuing the 2024.Ar quiet 2025command. 2026It is typically identical to 2027.Ar quiet . 2028.It Ar errFlag 2029The flag to pass the shell to enable error checking. 2030.It Ar echoFlag 2031The flag to pass the shell to enable command echoing. 2032.It Ar newline 2033The string literal to pass the shell that results in a single newline 2034character when used outside of any quoting characters. 2035.El 2036Example: 2037.Bd -literal 2038\&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e 2039 check="set \-e" ignore="set +e" \e 2040 echo="set \-v" quiet="set +v" filter="set +v" \e 2041 echoFlag=v errFlag=e newline="'\en'" 2042.Ed 2043.It Ic .SILENT 2044Apply the 2045.Ic .SILENT 2046attribute to any specified sources. 2047If no sources are specified, the 2048.Ic .SILENT 2049attribute is applied to every 2050command in the file. 2051.It Ic .STALE 2052This target gets run when a dependency file contains stale entries, having 2053.Va .ALLSRC 2054set to the name of that dependency file. 2055.It Ic .SUFFIXES 2056Each source specifies a suffix to 2057.Nm . 2058If no sources are specified, any previously specified suffixes are deleted. 2059It allows the creation of suffix-transformation rules. 2060.Pp 2061Example: 2062.Bd -literal 2063\&.SUFFIXES: .o 2064\&.c.o: 2065 cc \-o ${.TARGET} \-c ${.IMPSRC} 2066.Ed 2067.El 2068.Sh ENVIRONMENT 2069.Nm 2070uses the following environment variables, if they exist: 2071.Ev MACHINE , 2072.Ev MACHINE_ARCH , 2073.Ev MAKE , 2074.Ev MAKEFLAGS , 2075.Ev MAKEOBJDIR , 2076.Ev MAKEOBJDIRPREFIX , 2077.Ev MAKESYSPATH , 2078.Ev PWD , 2079and 2080.Ev TMPDIR . 2081.Pp 2082.Ev MAKEOBJDIRPREFIX 2083and 2084.Ev MAKEOBJDIR 2085may only be set in the environment or on the command line to 2086.Nm 2087and not as makefile variables; 2088see the description of 2089.Ql Va .OBJDIR 2090for more details. 2091.Sh FILES 2092.Bl -tag -width /usr/share/mk -compact 2093.It .depend 2094list of dependencies 2095.It Makefile 2096list of dependencies 2097.It makefile 2098list of dependencies 2099.It sys.mk 2100system makefile 2101.It /usr/share/mk 2102system makefile directory 2103.El 2104.Sh COMPATIBILITY 2105The basic make syntax is compatible between different versions of make, 2106however the special variables, variable modifiers and conditionals are not. 2107.Pp 2108The way that parallel makes are scheduled changed in 2109NetBSD 4.0 2110so that .ORDER and .WAIT apply recursively to the dependent nodes. 2111The algorithms used may change again in the future. 2112.Pp 2113The way that .for loop variables are substituted changed after 2114NetBSD 5.0 2115so that they still appear to be variable expansions. 2116In particular this stops them being treated as syntax, and removes some 2117obscure problems using them in .if statements. 2118.Sh SEE ALSO 2119.Xr mkdep 1 2120.Sh HISTORY 2121.Nm 2122is derived from NetBSD 2123.Xr make 1 . 2124It uses autoconf to facilitate portability to other platforms. 2125.Pp 2126A 2127make 2128command appeared in 2129.At v7 . 2130This 2131make 2132implementation is based on Adam De Boor's pmake program which was written 2133for Sprite at Berkeley. 2134It was designed to be a parallel distributed make running jobs on different 2135machines using a daemon called 2136.Dq customs . 2137.Pp 2138Historically the target/dependency 2139.Dq FRC 2140has been used to FoRCe rebuilding (since the target/dependency 2141does not exist... unless someone creates an 2142.Dq FRC 2143file). 2144.Sh BUGS 2145The 2146make 2147syntax is difficult to parse without actually acting of the data. 2148For instance finding the end of a variable use should involve scanning each 2149the modifiers using the correct terminator for each field. 2150In many places 2151make 2152just counts {} and () in order to find the end of a variable expansion. 2153.Pp 2154There is no way of escaping a space character in a filename. 2155