1.\" $NetBSD: make.1,v 1.262 2016/08/18 19:23:20 wiz 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 15, 2016 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 x 213Run shell commands with 214.Fl x 215so the actual commands are printed as they are executed. 216.El 217.It Fl e 218Specify that environment variables override macro assignments within 219makefiles. 220.It Fl f Ar makefile 221Specify a makefile to read instead of the default 222.Ql Pa makefile . 223If 224.Ar makefile 225is 226.Ql Fl , 227standard input is read. 228Multiple makefiles may be specified, and are read in the order specified. 229.It Fl I Ar directory 230Specify a directory in which to search for makefiles and included makefiles. 231The system makefile directory (or directories, see the 232.Fl m 233option) is automatically included as part of this list. 234.It Fl i 235Ignore non-zero exit of shell commands in the makefile. 236Equivalent to specifying 237.Ql Fl 238before each command line in the makefile. 239.It Fl J Ar private 240This option should 241.Em not 242be specified by the user. 243.Pp 244When the 245.Ar j 246option is in use in a recursive build, this option is passed by a make 247to child makes to allow all the make processes in the build to 248cooperate to avoid overloading the system. 249.It Fl j Ar max_jobs 250Specify the maximum number of jobs that 251.Nm 252may have running at any one time. 253The value is saved in 254.Va .MAKE.JOBS . 255Turns compatibility mode off, unless the 256.Ar B 257flag is also specified. 258When compatibility mode is off, all commands associated with a 259target are executed in a single shell invocation as opposed to the 260traditional one shell invocation per line. 261This can break traditional scripts which change directories on each 262command invocation and then expect to start with a fresh environment 263on the next line. 264It is more efficient to correct the scripts rather than turn backwards 265compatibility on. 266.It Fl k 267Continue processing after errors are encountered, but only on those targets 268that do not depend on the target whose creation caused the error. 269.It Fl m Ar directory 270Specify a directory in which to search for sys.mk and makefiles included 271via the 272.Ao Ar file Ac Ns -style 273include statement. 274The 275.Fl m 276option can be used multiple times to form a search path. 277This path will override the default system include path: /usr/share/mk. 278Furthermore the system include path will be appended to the search path used 279for 280.Qo Ar file Qc Ns -style 281include statements (see the 282.Fl I 283option). 284.Pp 285If a file or directory name in the 286.Fl m 287argument (or the 288.Ev MAKESYSPATH 289environment variable) starts with the string 290.Qq \&.../ 291then 292.Nm 293will search for the specified file or directory named in the remaining part 294of the argument string. 295The search starts with the current directory of 296the Makefile and then works upward towards the root of the file system. 297If the search is successful, then the resulting directory replaces the 298.Qq \&.../ 299specification in the 300.Fl m 301argument. 302If used, this feature allows 303.Nm 304to easily search in the current source tree for customized sys.mk files 305(e.g., by using 306.Qq \&.../mk/sys.mk 307as an argument). 308.It Fl n 309Display the commands that would have been executed, but do not 310actually execute them unless the target depends on the .MAKE special 311source (see below). 312.It Fl N 313Display the commands which would have been executed, but do not 314actually execute any of them; useful for debugging top-level makefiles 315without descending into subdirectories. 316.It Fl q 317Do not execute any commands, but exit 0 if the specified targets are 318up-to-date and 1, otherwise. 319.It Fl r 320Do not use the built-in rules specified in the system makefile. 321.It Fl s 322Do not echo any commands as they are executed. 323Equivalent to specifying 324.Ql Ic @ 325before each command line in the makefile. 326.It Fl T Ar tracefile 327When used with the 328.Fl j 329flag, 330append a trace record to 331.Ar tracefile 332for each job started and completed. 333.It Fl t 334Rather than re-building a target as specified in the makefile, create it 335or update its modification time to make it appear up-to-date. 336.It Fl V Ar variable 337Print 338.Nm Ns 's 339idea of the value of 340.Ar variable , 341in the global context. 342Do not build any targets. 343Multiple instances of this option may be specified; 344the variables will be printed one per line, 345with a blank line for each null or undefined variable. 346If 347.Ar variable 348contains a 349.Ql \&$ 350then the value will be expanded before printing. 351.It Fl W 352Treat any warnings during makefile parsing as errors. 353.It Fl w 354Print entering and leaving directory messages, pre and post processing. 355.It Fl X 356Don't export variables passed on the command line to the environment 357individually. 358Variables passed on the command line are still exported 359via the 360.Va MAKEFLAGS 361environment variable. 362This option may be useful on systems which have a small limit on the 363size of command arguments. 364.It Ar variable=value 365Set the value of the variable 366.Ar variable 367to 368.Ar value . 369Normally, all values passed on the command line are also exported to 370sub-makes in the environment. 371The 372.Fl X 373flag disables this behavior. 374Variable assignments should follow options for POSIX compatibility 375but no ordering is enforced. 376.El 377.Pp 378There are seven different types of lines in a makefile: file dependency 379specifications, shell commands, variable assignments, include statements, 380conditional directives, for loops, and comments. 381.Pp 382In general, lines may be continued from one line to the next by ending 383them with a backslash 384.Pq Ql \e . 385The trailing newline character and initial whitespace on the following 386line are compressed into a single space. 387.Sh FILE DEPENDENCY SPECIFICATIONS 388Dependency lines consist of one or more targets, an operator, and zero 389or more sources. 390This creates a relationship where the targets 391.Dq depend 392on the sources 393and are usually created from them. 394The exact relationship between the target and the source is determined 395by the operator that separates them. 396The three operators are as follows: 397.Bl -tag -width flag 398.It Ic \&: 399A target is considered out-of-date if its modification time is less than 400those of any of its sources. 401Sources for a target accumulate over dependency lines when this operator 402is used. 403The target is removed if 404.Nm 405is interrupted. 406.It Ic \&! 407Targets are always re-created, but not until all sources have been 408examined and re-created as necessary. 409Sources for a target accumulate over dependency lines when this operator 410is used. 411The target is removed if 412.Nm 413is interrupted. 414.It Ic \&:: 415If no sources are specified, the target is always re-created. 416Otherwise, a target is considered out-of-date if any of its sources has 417been modified more recently than the target. 418Sources for a target do not accumulate over dependency lines when this 419operator is used. 420The target will not be removed if 421.Nm 422is interrupted. 423.El 424.Pp 425Targets and sources may contain the shell wildcard values 426.Ql \&? , 427.Ql * , 428.Ql [] , 429and 430.Ql {} . 431The values 432.Ql \&? , 433.Ql * , 434and 435.Ql [] 436may only be used as part of the final 437component of the target or source, and must be used to describe existing 438files. 439The value 440.Ql {} 441need not necessarily be used to describe existing files. 442Expansion is in directory order, not alphabetically as done in the shell. 443.Sh SHELL COMMANDS 444Each target may have associated with it one or more lines of shell 445commands, normally 446used to create the target. 447Each of the lines in this script 448.Em must 449be preceded by a tab. 450(For historical reasons, spaces are not accepted.) 451While targets can appear in many dependency lines if desired, by 452default only one of these rules may be followed by a creation 453script. 454If the 455.Ql Ic \&:: 456operator is used, however, all rules may include scripts and the 457scripts are executed in the order found. 458.Pp 459Each line is treated as a separate shell command, unless the end of 460line is escaped with a backslash 461.Pq Ql \e 462in which case that line and the next are combined. 463.\" The escaped newline is retained and passed to the shell, which 464.\" normally ignores it. 465.\" However, the tab at the beginning of the following line is removed. 466If the first characters of the command are any combination of 467.Ql Ic @ , 468.Ql Ic + , 469or 470.Ql Ic \- , 471the command is treated specially. 472A 473.Ql Ic @ 474causes the command not to be echoed before it is executed. 475A 476.Ql Ic + 477causes the command to be executed even when 478.Fl n 479is given. 480This is similar to the effect of the .MAKE special source, 481except that the effect can be limited to a single line of a script. 482A 483.Ql Ic \- 484in compatibility mode 485causes any non-zero exit status of the command line to be ignored. 486.Pp 487When 488.Nm 489is run in jobs mode with 490.Fl j Ar max_jobs , 491the entire script for the target is fed to a 492single instance of the shell. 493In compatibility (non-jobs) mode, each command is run in a separate process. 494If the command contains any shell meta characters 495.Pq Ql #=|^(){};&<>*?[]:$`\e\en 496it will be passed to the shell; otherwise 497.Nm 498will attempt direct execution. 499If a line starts with 500.Ql Ic \- 501and the shell has ErrCtl enabled then failure of the command line 502will be ignored as in compatibility mode. 503Otherwise 504.Ql Ic \- 505affects the entire job; 506the script will stop at the first command line that fails, 507but the target will not be deemed to have failed. 508.Pp 509Makefiles should be written so that the mode of 510.Nm 511operation does not change their behavior. 512For example, any command which needs to use 513.Dq cd 514or 515.Dq chdir 516without potentially changing the directory for subsequent commands 517should be put in parentheses so it executes in a subshell. 518To force the use of one shell, escape the line breaks so as to make 519the whole script one command. 520For example: 521.Bd -literal -offset indent 522avoid-chdir-side-effects: 523 @echo Building $@ in `pwd` 524 @(cd ${.CURDIR} && ${MAKE} $@) 525 @echo Back in `pwd` 526 527ensure-one-shell-regardless-of-mode: 528 @echo Building $@ in `pwd`; \e 529 (cd ${.CURDIR} && ${MAKE} $@); \e 530 echo Back in `pwd` 531.Ed 532.Pp 533Since 534.Nm 535will 536.Xr chdir 2 537to 538.Ql Va .OBJDIR 539before executing any targets, each child process 540starts with that as its current working directory. 541.Sh VARIABLE ASSIGNMENTS 542Variables in make are much like variables in the shell, and, by tradition, 543consist of all upper-case letters. 544.Ss Variable assignment modifiers 545The five operators that can be used to assign values to variables are as 546follows: 547.Bl -tag -width Ds 548.It Ic \&= 549Assign the value to the variable. 550Any previous value is overridden. 551.It Ic \&+= 552Append the value to the current value of the variable. 553.It Ic \&?= 554Assign the value to the variable if it is not already defined. 555.It Ic \&:= 556Assign with expansion, i.e. expand the value before assigning it 557to the variable. 558Normally, expansion is not done until the variable is referenced. 559.Em NOTE : 560References to undefined variables are 561.Em not 562expanded. 563This can cause problems when variable modifiers are used. 564.It Ic \&!= 565Expand the value and pass it to the shell for execution and assign 566the result to the variable. 567Any newlines in the result are replaced with spaces. 568.El 569.Pp 570Any white-space before the assigned 571.Ar value 572is removed; if the value is being appended, a single space is inserted 573between the previous contents of the variable and the appended value. 574.Pp 575Variables are expanded by surrounding the variable name with either 576curly braces 577.Pq Ql {} 578or parentheses 579.Pq Ql () 580and preceding it with 581a dollar sign 582.Pq Ql \&$ . 583If the variable name contains only a single letter, the surrounding 584braces or parentheses are not required. 585This shorter form is not recommended. 586.Pp 587If the variable name contains a dollar, then the name itself is expanded first. 588This allows almost arbitrary variable names, however names containing dollar, 589braces, parenthesis, or whitespace are really best avoided! 590.Pp 591If the result of expanding a variable contains a dollar sign 592.Pq Ql \&$ 593the string is expanded again. 594.Pp 595Variable substitution occurs at three distinct times, depending on where 596the variable is being used. 597.Bl -enum 598.It 599Variables in dependency lines are expanded as the line is read. 600.It 601Variables in shell commands are expanded when the shell command is 602executed. 603.It 604.Dq .for 605loop index variables are expanded on each loop iteration. 606Note that other variables are not expanded inside loops so 607the following example code: 608.Bd -literal -offset indent 609 610.Dv .for i in 1 2 3 611a+= ${i} 612j= ${i} 613b+= ${j} 614.Dv .endfor 615 616all: 617 @echo ${a} 618 @echo ${b} 619 620.Ed 621will print: 622.Bd -literal -offset indent 6231 2 3 6243 3 3 625 626.Ed 627Because while ${a} contains 628.Dq 1 2 3 629after the loop is executed, ${b} 630contains 631.Dq ${j} ${j} ${j} 632which expands to 633.Dq 3 3 3 634since after the loop completes ${j} contains 635.Dq 3 . 636.El 637.Ss Variable classes 638The four different classes of variables (in order of increasing precedence) 639are: 640.Bl -tag -width Ds 641.It Environment variables 642Variables defined as part of 643.Nm Ns 's 644environment. 645.It Global variables 646Variables defined in the makefile or in included makefiles. 647.It Command line variables 648Variables defined as part of the command line. 649.It Local variables 650Variables that are defined specific to a certain target. 651.El 652.Pp 653Local variables are all built in and their values vary magically from 654target to target. 655It is not currently possible to define new local variables. 656The seven local variables are as follows: 657.Bl -tag -width ".ARCHIVE" -offset indent 658.It Va .ALLSRC 659The list of all sources for this target; also known as 660.Ql Va \&\*[Gt] . 661.It Va .ARCHIVE 662The name of the archive file; also known as 663.Ql Va \&! . 664.It Va .IMPSRC 665In suffix-transformation rules, the name/path of the source from which the 666target is to be transformed (the 667.Dq implied 668source); also known as 669.Ql Va \&\*[Lt] . 670It is not defined in explicit rules. 671.It Va .MEMBER 672The name of the archive member; also known as 673.Ql Va % . 674.It Va .OODATE 675The list of sources for this target that were deemed out-of-date; also 676known as 677.Ql Va \&? . 678.It Va .PREFIX 679The file prefix of the target, containing only the file portion, no suffix 680or preceding directory components; also known as 681.Ql Va * . 682The suffix must be one of the known suffixes declared with 683.Ic .SUFFIXES 684or it will not be recognized. 685.It Va .TARGET 686The name of the target; also known as 687.Ql Va @ . 688For compatibility with other makes this is an alias for 689.Ic .ARCHIVE 690in archive member rules. 691.El 692.Pp 693The shorter forms 694.Ql ( Va \*[Gt] , 695.Ql Va \&! , 696.Ql Va \*[Lt] , 697.Ql Va % , 698.Ql Va \&? , 699.Ql Va * , 700and 701.Ql Va @ ) 702are permitted for backward 703compatibility with historical makefiles and legacy POSIX make and are 704not recommended. 705.Pp 706Variants of these variables with the punctuation followed immediately by 707.Ql D 708or 709.Ql F , 710e.g. 711.Ql Va $(@D) , 712are legacy forms equivalent to using the 713.Ql :H 714and 715.Ql :T 716modifiers. 717These forms are accepted for compatibility with 718.At V 719makefiles and POSIX but are not recommended. 720.Pp 721Four of the local variables may be used in sources on dependency lines 722because they expand to the proper value for each target on the line. 723These variables are 724.Ql Va .TARGET , 725.Ql Va .PREFIX , 726.Ql Va .ARCHIVE , 727and 728.Ql Va .MEMBER . 729.Ss Additional built-in variables 730In addition, 731.Nm 732sets or knows about the following variables: 733.Bl -tag -width .MAKEOVERRIDES 734.It Va \&$ 735A single dollar sign 736.Ql \&$ , 737i.e. 738.Ql \&$$ 739expands to a single dollar 740sign. 741.It Va .ALLTARGETS 742The list of all targets encountered in the Makefile. 743If evaluated during 744Makefile parsing, lists only those targets encountered thus far. 745.It Va .CURDIR 746A path to the directory where 747.Nm 748was executed. 749Refer to the description of 750.Ql Ev PWD 751for more details. 752.It Va .INCLUDEDFROMDIR 753The directory of the file this Makefile was included from. 754.It Va .INCLUDEDFROMFILE 755The filename of the file this Makefile was included from. 756.It Ev MAKE 757The name that 758.Nm 759was executed with 760.Pq Va argv[0] . 761For compatibility 762.Nm 763also sets 764.Va .MAKE 765with the same value. 766The preferred variable to use is the environment variable 767.Ev MAKE 768because it is more compatible with other versions of 769.Nm 770and cannot be confused with the special target with the same name. 771.It Va .MAKE.DEPENDFILE 772Names the makefile (default 773.Ql Pa .depend ) 774from which generated dependencies are read. 775.It Va .MAKE.EXPAND_VARIABLES 776A boolean that controls the default behavior of the 777.Fl V 778option. 779.It Va .MAKE.EXPORTED 780The list of variables exported by 781.Nm . 782.It Va .MAKE.JOBS 783The argument to the 784.Fl j 785option. 786.It Va .MAKE.JOB.PREFIX 787If 788.Nm 789is run with 790.Ar j 791then output for each target is prefixed with a token 792.Ql --- target --- 793the first part of which can be controlled via 794.Va .MAKE.JOB.PREFIX . 795If 796.Va .MAKE.JOB.PREFIX 797is empty, no token is printed. 798.br 799For example: 800.Li .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}] 801would produce tokens like 802.Ql ---make[1234] target --- 803making it easier to track the degree of parallelism being achieved. 804.It Ev MAKEFLAGS 805The environment variable 806.Ql Ev MAKEFLAGS 807may contain anything that 808may be specified on 809.Nm Ns 's 810command line. 811Anything specified on 812.Nm Ns 's 813command line is appended to the 814.Ql Ev MAKEFLAGS 815variable which is then 816entered into the environment for all programs which 817.Nm 818executes. 819.It Va .MAKE.LEVEL 820The recursion depth of 821.Nm . 822The initial instance of 823.Nm 824will be 0, and an incremented value is put into the environment 825to be seen by the next generation. 826This allows tests like: 827.Li .if ${.MAKE.LEVEL} == 0 828to protect things which should only be evaluated in the initial instance of 829.Nm . 830.It Va .MAKE.MAKEFILE_PREFERENCE 831The ordered list of makefile names 832(default 833.Ql Pa makefile , 834.Ql Pa Makefile ) 835that 836.Nm 837will look for. 838.It Va .MAKE.MAKEFILES 839The list of makefiles read by 840.Nm , 841which is useful for tracking dependencies. 842Each makefile is recorded only once, regardless of the number of times read. 843.It Va .MAKE.MODE 844Processed after reading all makefiles. 845Can affect the mode that 846.Nm 847runs in. 848It can contain a number of keywords: 849.Bl -hang -width missing-filemon=bf. 850.It Pa compat 851Like 852.Fl B , 853puts 854.Nm 855into "compat" mode. 856.It Pa meta 857Puts 858.Nm 859into "meta" mode, where meta files are created for each target 860to capture the command run, the output generated and if 861.Xr filemon 4 862is available, the system calls which are of interest to 863.Nm . 864The captured output can be very useful when diagnosing errors. 865.It Pa curdirOk= Ar bf 866Normally 867.Nm 868will not create .meta files in 869.Ql Va .CURDIR . 870This can be overridden by setting 871.Va bf 872to a value which represents True. 873.It Pa missing-meta= Ar bf 874If 875.Va bf 876is True, then a missing .meta file makes the target out-of-date. 877.It Pa missing-filemon= Ar bf 878If 879.Va bf 880is True, then missing filemon data makes the target out-of-date. 881.It Pa nofilemon 882Do not use 883.Xr filemon 4 . 884.It Pa env 885For debugging, it can be useful to include the environment 886in the .meta file. 887.It Pa verbose 888If in "meta" mode, print a clue about the target being built. 889This is useful if the build is otherwise running silently. 890The message printed the value of: 891.Va .MAKE.META.PREFIX . 892.It Pa ignore-cmd 893Some makefiles have commands which are simply not stable. 894This keyword causes them to be ignored for 895determining whether a target is out of date in "meta" mode. 896See also 897.Ic .NOMETA_CMP . 898.It Pa silent= Ar bf 899If 900.Va bf 901is True, when a .meta file is created, mark the target 902.Ic .SILENT . 903.El 904.It Va .MAKE.META.BAILIWICK 905In "meta" mode, provides a list of prefixes which 906match the directories controlled by 907.Nm . 908If a file that was generated outside of 909.Va .OBJDIR 910but within said bailiwick is missing, 911the current target is considered out-of-date. 912.It Va .MAKE.META.CREATED 913In "meta" mode, this variable contains a list of all the meta files 914updated. 915If not empty, it can be used to trigger processing of 916.Va .MAKE.META.FILES . 917.It Va .MAKE.META.FILES 918In "meta" mode, this variable contains a list of all the meta files 919used (updated or not). 920This list can be used to process the meta files to extract dependency 921information. 922.It Va .MAKE.META.IGNORE_PATHS 923Provides a list of path prefixes that should be ignored; 924because the contents are expected to change over time. 925The default list includes: 926.Ql Pa /dev /etc /proc /tmp /var/run /var/tmp 927.It Va .MAKE.META.IGNORE_PATTERNS 928Provides a list of patterns to match against pathnames. 929Ignore any that match. 930.It Va .MAKE.META.IGNORE_FILTER 931Provides a list of variable modifiers to apply to each pathname. 932Ignore if the expansion is an empty string. 933.It Va .MAKE.META.PREFIX 934Defines the message printed for each meta file updated in "meta verbose" mode. 935The default value is: 936.Dl Building ${.TARGET:H:tA}/${.TARGET:T} 937.It Va .MAKEOVERRIDES 938This variable is used to record the names of variables assigned to 939on the command line, so that they may be exported as part of 940.Ql Ev MAKEFLAGS . 941This behavior can be disabled by assigning an empty value to 942.Ql Va .MAKEOVERRIDES 943within a makefile. 944Extra variables can be exported from a makefile 945by appending their names to 946.Ql Va .MAKEOVERRIDES . 947.Ql Ev MAKEFLAGS 948is re-exported whenever 949.Ql Va .MAKEOVERRIDES 950is modified. 951.It Va .MAKE.PATH_FILEMON 952If 953.Nm 954was built with 955.Xr filemon 4 956support, this is set to the path of the device node. 957This allows makefiles to test for this support. 958.It Va .MAKE.PID 959The process-id of 960.Nm . 961.It Va .MAKE.PPID 962The parent process-id of 963.Nm . 964.It Va .MAKE.BUILT.BY 965The compiler CCVER that built the 966.Dx 967world. 968.It Va .MAKE.DF.OSREL 969The 970.Dx 971version when the world was built. It is in the "<major>.<minor>" 972format and it used by DPorts. 973.It Va .MAKE.DF.VERSION 974The value of __DragonFly_version when the 975.Dx 976world was built. It is used by DPorts. 977.It Va .MAKE.SAVE_DOLLARS 978value should be a boolean that controls whether 979.Ql $$ 980are preserved when doing 981.Ql := 982assignments. 983The default is false, for backwards compatibility. 984Set to true for compatibility with other makes. 985If set to false, 986.Ql $$ 987becomes 988.Ql $ 989per normal evaluation rules. 990.It Va MAKE_PRINT_VAR_ON_ERROR 991When 992.Nm 993stops due to an error, it sets 994.Ql Va .ERROR_TARGET 995to the name of the target that failed, 996.Ql Va .ERROR_CMD 997to the commands of the failed target, 998and in "meta" mode, it also sets 999.Ql Va .ERROR_CWD 1000to the 1001.Xr getcwd 3 , 1002and 1003.Ql Va .ERROR_META_FILE 1004to the path of the meta file (if any) describing the failed target. 1005It then prints its name and the value of 1006.Ql Va .CURDIR 1007as well as the value of any variables named in 1008.Ql Va MAKE_PRINT_VAR_ON_ERROR . 1009.It Va .newline 1010This variable is simply assigned a newline character as its value. 1011This allows expansions using the 1012.Cm \&:@ 1013modifier to put a newline between 1014iterations of the loop rather than a space. 1015For example, the printing of 1016.Ql Va MAKE_PRINT_VAR_ON_ERROR 1017could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}. 1018.It Va .OBJDIR 1019A path to the directory where the targets are built. 1020Its value is determined by trying to 1021.Xr chdir 2 1022to the following directories in order and using the first match: 1023.Bl -enum 1024.It 1025.Ev ${MAKEOBJDIRPREFIX}${.CURDIR} 1026.Pp 1027(Only if 1028.Ql Ev MAKEOBJDIRPREFIX 1029is set in the environment or on the command line.) 1030.It 1031.Ev ${MAKEOBJDIR} 1032.Pp 1033(Only if 1034.Ql Ev MAKEOBJDIR 1035is set in the environment or on the command line.) 1036.It 1037.Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE} 1038.It 1039.Ev ${.CURDIR} Ns Pa /obj 1040.It 1041.Pa /usr/obj/ Ns Ev ${.CURDIR} 1042.It 1043.Ev ${.CURDIR} 1044.El 1045.Pp 1046Variable expansion is performed on the value before it's used, 1047so expressions such as 1048.Dl ${.CURDIR:S,^/usr/src,/var/obj,} 1049may be used. 1050This is especially useful with 1051.Ql Ev MAKEOBJDIR . 1052.Pp 1053.Ql Va .OBJDIR 1054may be modified in the makefile via the special target 1055.Ql Ic .OBJDIR . 1056In all cases, 1057.Nm 1058will 1059.Xr chdir 2 1060to the specified directory if it exists, and set 1061.Ql Va .OBJDIR 1062and 1063.Ql Ev PWD 1064to that directory before executing any targets. 1065. 1066.It Va .PARSEDIR 1067A path to the directory of the current 1068.Ql Pa Makefile 1069being parsed. 1070.It Va .PARSEFILE 1071The basename of the current 1072.Ql Pa Makefile 1073being parsed. 1074This variable and 1075.Ql Va .PARSEDIR 1076are both set only while the 1077.Ql Pa Makefiles 1078are being parsed. 1079If you want to retain their current values, assign them to a variable 1080using assignment with expansion: 1081.Pq Ql Cm \&:= . 1082.It Va .PATH 1083A variable that represents the list of directories that 1084.Nm 1085will search for files. 1086The search list should be updated using the target 1087.Ql Va .PATH 1088rather than the variable. 1089.It Ev PWD 1090Alternate path to the current directory. 1091.Nm 1092normally sets 1093.Ql Va .CURDIR 1094to the canonical path given by 1095.Xr getcwd 3 . 1096However, if the environment variable 1097.Ql Ev PWD 1098is set and gives a path to the current directory, then 1099.Nm 1100sets 1101.Ql Va .CURDIR 1102to the value of 1103.Ql Ev PWD 1104instead. 1105This behavior is disabled if 1106.Ql Ev MAKEOBJDIRPREFIX 1107is set or 1108.Ql Ev MAKEOBJDIR 1109contains a variable transform. 1110.Ql Ev PWD 1111is set to the value of 1112.Ql Va .OBJDIR 1113for all programs which 1114.Nm 1115executes. 1116.It Ev .TARGETS 1117The list of targets explicitly specified on the command line, if any. 1118.It Ev VPATH 1119Colon-separated 1120.Pq Dq \&: 1121lists of directories that 1122.Nm 1123will search for files. 1124The variable is supported for compatibility with old make programs only, 1125use 1126.Ql Va .PATH 1127instead. 1128.El 1129.Ss Variable modifiers 1130Variable expansion may be modified to select or modify each word of the 1131variable (where a 1132.Dq word 1133is white-space delimited sequence of characters). 1134The general format of a variable expansion is as follows: 1135.Pp 1136.Dl ${variable[:modifier[:...]]} 1137.Pp 1138Each modifier begins with a colon, 1139which may be escaped with a backslash 1140.Pq Ql \e . 1141.Pp 1142A set of modifiers can be specified via a variable, as follows: 1143.Pp 1144.Dl modifier_variable=modifier[:...] 1145.Dl ${variable:${modifier_variable}[:...]} 1146.Pp 1147In this case the first modifier in the modifier_variable does not 1148start with a colon, since that must appear in the referencing 1149variable. 1150If any of the modifiers in the modifier_variable contain a dollar sign 1151.Pq Ql $ , 1152these must be doubled to avoid early expansion. 1153.Pp 1154The supported modifiers are: 1155.Bl -tag -width EEE 1156.It Cm \&:E 1157Replaces each word in the variable with its suffix. 1158.It Cm \&:H 1159Replaces each word in the variable with everything but the last component. 1160.It Cm \&:M Ns Ar pattern 1161Select only those words that match 1162.Ar pattern . 1163The standard shell wildcard characters 1164.Pf ( Ql * , 1165.Ql \&? , 1166and 1167.Ql Oo Oc ) 1168may 1169be used. 1170The wildcard characters may be escaped with a backslash 1171.Pq Ql \e . 1172As a consequence of the way values are split into words, matched, 1173and then joined, a construct like 1174.Dl ${VAR:M*} 1175will normalize the inter-word spacing, removing all leading and 1176trailing space, and converting multiple consecutive spaces 1177to single spaces. 1178. 1179.It Cm \&:N Ns Ar pattern 1180This is identical to 1181.Ql Cm \&:M , 1182but selects all words which do not match 1183.Ar pattern . 1184.It Cm \&:O 1185Order every word in variable alphabetically. 1186To sort words in 1187reverse order use the 1188.Ql Cm \&:O:[-1..1] 1189combination of modifiers. 1190.It Cm \&:Ox 1191Randomize words in variable. 1192The results will be different each time you are referring to the 1193modified variable; use the assignment with expansion 1194.Pq Ql Cm \&:= 1195to prevent such behavior. 1196For example, 1197.Bd -literal -offset indent 1198LIST= uno due tre quattro 1199RANDOM_LIST= ${LIST:Ox} 1200STATIC_RANDOM_LIST:= ${LIST:Ox} 1201 1202all: 1203 @echo "${RANDOM_LIST}" 1204 @echo "${RANDOM_LIST}" 1205 @echo "${STATIC_RANDOM_LIST}" 1206 @echo "${STATIC_RANDOM_LIST}" 1207.Ed 1208may produce output similar to: 1209.Bd -literal -offset indent 1210quattro due tre uno 1211tre due quattro uno 1212due uno quattro tre 1213due uno quattro tre 1214.Ed 1215.It Cm \&:Q 1216Quotes every shell meta-character in the variable, so that it can be passed 1217safely through recursive invocations of 1218.Nm . 1219.It Cm \&:R 1220Replaces each word in the variable with everything but its suffix. 1221.It Cm \&:gmtime 1222The value is a format string for 1223.Xr strftime 3 , 1224using the current 1225.Xr gmtime 3 . 1226.It Cm \&:hash 1227Compute a 32-bit hash of the value and encode it as hex digits. 1228.It Cm \&:localtime 1229The value is a format string for 1230.Xr strftime 3 , 1231using the current 1232.Xr localtime 3 . 1233.It Cm \&:tA 1234Attempt to convert variable to an absolute path using 1235.Xr realpath 3 , 1236if that fails, the value is unchanged. 1237.It Cm \&:tl 1238Converts variable to lower-case letters. 1239.It Cm \&:ts Ns Ar c 1240Words in the variable are normally separated by a space on expansion. 1241This modifier sets the separator to the character 1242.Ar c . 1243If 1244.Ar c 1245is omitted, then no separator is used. 1246The common escapes (including octal numeric codes), work as expected. 1247.It Cm \&:tu 1248Converts variable to upper-case letters. 1249.It Cm \&:tW 1250Causes the value to be treated as a single word 1251(possibly containing embedded white space). 1252See also 1253.Ql Cm \&:[*] . 1254.It Cm \&:tw 1255Causes the value to be treated as a sequence of 1256words delimited by white space. 1257See also 1258.Ql Cm \&:[@] . 1259.Sm off 1260.It Cm \&:S No \&/ Ar old_string No \&/ Ar new_string No \&/ Op Cm 1gW 1261.Sm on 1262Modify the first occurrence of 1263.Ar old_string 1264in the variable's value, replacing it with 1265.Ar new_string . 1266If a 1267.Ql g 1268is appended to the last slash of the pattern, all occurrences 1269in each word are replaced. 1270If a 1271.Ql 1 1272is appended to the last slash of the pattern, only the first word 1273is affected. 1274If a 1275.Ql W 1276is appended to the last slash of the pattern, 1277then the value is treated as a single word 1278(possibly containing embedded white space). 1279If 1280.Ar old_string 1281begins with a caret 1282.Pq Ql ^ , 1283.Ar old_string 1284is anchored at the beginning of each word. 1285If 1286.Ar old_string 1287ends with a dollar sign 1288.Pq Ql \&$ , 1289it is anchored at the end of each word. 1290Inside 1291.Ar new_string , 1292an ampersand 1293.Pq Ql \*[Am] 1294is replaced by 1295.Ar old_string 1296(without any 1297.Ql ^ 1298or 1299.Ql \&$ ) . 1300Any character may be used as a delimiter for the parts of the modifier 1301string. 1302The anchoring, ampersand and delimiter characters may be escaped with a 1303backslash 1304.Pq Ql \e . 1305.Pp 1306Variable expansion occurs in the normal fashion inside both 1307.Ar old_string 1308and 1309.Ar new_string 1310with the single exception that a backslash is used to prevent the expansion 1311of a dollar sign 1312.Pq Ql \&$ , 1313not a preceding dollar sign as is usual. 1314.Sm off 1315.It Cm \&:C No \&/ Ar pattern No \&/ Ar replacement No \&/ Op Cm 1gW 1316.Sm on 1317The 1318.Cm \&:C 1319modifier is just like the 1320.Cm \&:S 1321modifier except that the old and new strings, instead of being 1322simple strings, are an extended regular expression (see 1323.Xr regex 3 ) 1324string 1325.Ar pattern 1326and an 1327.Xr ed 1 Ns \-style 1328string 1329.Ar replacement . 1330Normally, the first occurrence of the pattern 1331.Ar pattern 1332in each word of the value is substituted with 1333.Ar replacement . 1334The 1335.Ql 1 1336modifier causes the substitution to apply to at most one word; the 1337.Ql g 1338modifier causes the substitution to apply to as many instances of the 1339search pattern 1340.Ar pattern 1341as occur in the word or words it is found in; the 1342.Ql W 1343modifier causes the value to be treated as a single word 1344(possibly containing embedded white space). 1345Note that 1346.Ql 1 1347and 1348.Ql g 1349are orthogonal; the former specifies whether multiple words are 1350potentially affected, the latter whether multiple substitutions can 1351potentially occur within each affected word. 1352.Pp 1353As for the 1354.Cm \&:S 1355modifier, the 1356.Ar pattern 1357and 1358.Ar replacement 1359are subjected to variable expansion before being parsed as 1360regular expressions. 1361.It Cm \&:T 1362Replaces each word in the variable with its last component. 1363.It Cm \&:u 1364Remove adjacent duplicate words (like 1365.Xr uniq 1 ) . 1366.Sm off 1367.It Cm \&:\&? Ar true_string Cm \&: Ar false_string 1368.Sm on 1369If the variable name (not its value), when parsed as a .if conditional 1370expression, evaluates to true, return as its value the 1371.Ar true_string , 1372otherwise return the 1373.Ar false_string . 1374Since the variable name is used as the expression, \&:\&? must be the 1375first modifier after the variable name itself - which will, of course, 1376usually contain variable expansions. 1377A common error is trying to use expressions like 1378.Dl ${NUMBERS:M42:?match:no} 1379which actually tests defined(NUMBERS), 1380to determine is any words match "42" you need to use something like: 1381.Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} . 1382.It Ar :old_string=new_string 1383This is the 1384.At V 1385style variable substitution. 1386It must be the last modifier specified. 1387If 1388.Ar old_string 1389or 1390.Ar new_string 1391do not contain the pattern matching character 1392.Ar % 1393then it is assumed that they are 1394anchored at the end of each word, so only suffixes or entire 1395words may be replaced. 1396Otherwise 1397.Ar % 1398is the substring of 1399.Ar old_string 1400to be replaced in 1401.Ar new_string . 1402.Pp 1403Variable expansion occurs in the normal fashion inside both 1404.Ar old_string 1405and 1406.Ar new_string 1407with the single exception that a backslash is used to prevent the 1408expansion of a dollar sign 1409.Pq Ql \&$ , 1410not a preceding dollar sign as is usual. 1411.Sm off 1412.It Cm \&:@ Ar temp Cm @ Ar string Cm @ 1413.Sm on 1414This is the loop expansion mechanism from the OSF Development 1415Environment (ODE) make. 1416Unlike 1417.Cm \&.for 1418loops expansion occurs at the time of 1419reference. 1420Assign 1421.Ar temp 1422to each word in the variable and evaluate 1423.Ar string . 1424The ODE convention is that 1425.Ar temp 1426should start and end with a period. 1427For example. 1428.Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@} 1429.Pp 1430However a single character variable is often more readable: 1431.Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@} 1432.It Cm \&:U Ns Ar newval 1433If the variable is undefined 1434.Ar newval 1435is the value. 1436If the variable is defined, the existing value is returned. 1437This is another ODE make feature. 1438It is handy for setting per-target CFLAGS for instance: 1439.Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}} 1440If a value is only required if the variable is undefined, use: 1441.Dl ${VAR:D:Unewval} 1442.It Cm \&:D Ns Ar newval 1443If the variable is defined 1444.Ar newval 1445is the value. 1446.It Cm \&:L 1447The name of the variable is the value. 1448.It Cm \&:P 1449The path of the node which has the same name as the variable 1450is the value. 1451If no such node exists or its path is null, then the 1452name of the variable is used. 1453In order for this modifier to work, the name (node) must at least have 1454appeared on the rhs of a dependency. 1455.Sm off 1456.It Cm \&:\&! Ar cmd Cm \&! 1457.Sm on 1458The output of running 1459.Ar cmd 1460is the value. 1461.It Cm \&:sh 1462If the variable is non-empty it is run as a command and the output 1463becomes the new value. 1464.It Cm \&::= Ns Ar str 1465The variable is assigned the value 1466.Ar str 1467after substitution. 1468This modifier and its variations are useful in 1469obscure situations such as wanting to set a variable when shell commands 1470are being parsed. 1471These assignment modifiers always expand to 1472nothing, so if appearing in a rule line by themselves should be 1473preceded with something to keep 1474.Nm 1475happy. 1476.Pp 1477The 1478.Ql Cm \&:: 1479helps avoid false matches with the 1480.At V 1481style 1482.Cm \&:= 1483modifier and since substitution always occurs the 1484.Cm \&::= 1485form is vaguely appropriate. 1486.It Cm \&::?= Ns Ar str 1487As for 1488.Cm \&::= 1489but only if the variable does not already have a value. 1490.It Cm \&::+= Ns Ar str 1491Append 1492.Ar str 1493to the variable. 1494.It Cm \&::!= Ns Ar cmd 1495Assign the output of 1496.Ar cmd 1497to the variable. 1498.It Cm \&:\&[ Ns Ar range Ns Cm \&] 1499Selects one or more words from the value, 1500or performs other operations related to the way in which the 1501value is divided into words. 1502.Pp 1503Ordinarily, a value is treated as a sequence of words 1504delimited by white space. 1505Some modifiers suppress this behavior, 1506causing a value to be treated as a single word 1507(possibly containing embedded white space). 1508An empty value, or a value that consists entirely of white-space, 1509is treated as a single word. 1510For the purposes of the 1511.Ql Cm \&:[] 1512modifier, the words are indexed both forwards using positive integers 1513(where index 1 represents the first word), 1514and backwards using negative integers 1515(where index \-1 represents the last word). 1516.Pp 1517The 1518.Ar range 1519is subjected to variable expansion, and the expanded result is 1520then interpreted as follows: 1521.Bl -tag -width index 1522.\" :[n] 1523.It Ar index 1524Selects a single word from the value. 1525.\" :[start..end] 1526.It Ar start Ns Cm \&.. Ns Ar end 1527Selects all words from 1528.Ar start 1529to 1530.Ar end , 1531inclusive. 1532For example, 1533.Ql Cm \&:[2..-1] 1534selects all words from the second word to the last word. 1535If 1536.Ar start 1537is greater than 1538.Ar end , 1539then the words are output in reverse order. 1540For example, 1541.Ql Cm \&:[-1..1] 1542selects all the words from last to first. 1543.\" :[*] 1544.It Cm \&* 1545Causes subsequent modifiers to treat the value as a single word 1546(possibly containing embedded white space). 1547Analogous to the effect of 1548\&"$*\&" 1549in Bourne shell. 1550.\" :[0] 1551.It 0 1552Means the same as 1553.Ql Cm \&:[*] . 1554.\" :[*] 1555.It Cm \&@ 1556Causes subsequent modifiers to treat the value as a sequence of words 1557delimited by white space. 1558Analogous to the effect of 1559\&"$@\&" 1560in Bourne shell. 1561.\" :[#] 1562.It Cm \&# 1563Returns the number of words in the value. 1564.El \" :[range] 1565.El 1566.Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS 1567Makefile inclusion, conditional structures and for loops reminiscent 1568of the C programming language are provided in 1569.Nm . 1570All such structures are identified by a line beginning with a single 1571dot 1572.Pq Ql \&. 1573character. 1574Files are included with either 1575.Cm \&.include Aq Ar file 1576or 1577.Cm \&.include Pf \*q Ar file Ns \*q . 1578Variables between the angle brackets or double quotes are expanded 1579to form the file name. 1580If angle brackets are used, the included makefile is expected to be in 1581the system makefile directory. 1582If double quotes are used, the including makefile's directory and any 1583directories specified using the 1584.Fl I 1585option are searched before the system 1586makefile directory. 1587For compatibility with other versions of 1588.Nm 1589.Ql include file ... 1590is also accepted. 1591.Pp 1592If the include statement is written as 1593.Cm .-include 1594or as 1595.Cm .sinclude 1596then errors locating and/or opening include files are ignored. 1597.Pp 1598If the include statement is written as 1599.Cm .dinclude 1600not only are errors locating and/or opening include files ignored, 1601but stale dependencies within the included file will be ignored 1602just like 1603.Va .MAKE.DEPENDFILE . 1604.Pp 1605Conditional expressions are also preceded by a single dot as the first 1606character of a line. 1607The possible conditionals are as follows: 1608.Bl -tag -width Ds 1609.It Ic .error Ar message 1610The message is printed along with the name of the makefile and line number, 1611then 1612.Nm 1613will exit. 1614.It Ic .export Ar variable ... 1615Export the specified global variable. 1616If no variable list is provided, all globals are exported 1617except for internal variables (those that start with 1618.Ql \&. ) . 1619This is not affected by the 1620.Fl X 1621flag, so should be used with caution. 1622For compatibility with other 1623.Nm 1624programs 1625.Ql export variable=value 1626is also accepted. 1627.Pp 1628Appending a variable name to 1629.Va .MAKE.EXPORTED 1630is equivalent to exporting a variable. 1631.It Ic .export-env Ar variable ... 1632The same as 1633.Ql .export , 1634except that the variable is not appended to 1635.Va .MAKE.EXPORTED . 1636This allows exporting a value to the environment which is different from that 1637used by 1638.Nm 1639internally. 1640.It Ic .export-literal Ar variable ... 1641The same as 1642.Ql .export-env , 1643except that variables in the value are not expanded. 1644.It Ic .info Ar message 1645The message is printed along with the name of the makefile and line number. 1646.It Ic .undef Ar variable 1647Un-define the specified global variable. 1648Only global variables may be un-defined. 1649.It Ic .unexport Ar variable ... 1650The opposite of 1651.Ql .export . 1652The specified global 1653.Va variable 1654will be removed from 1655.Va .MAKE.EXPORTED . 1656If no variable list is provided, all globals are unexported, 1657and 1658.Va .MAKE.EXPORTED 1659deleted. 1660.It Ic .unexport-env 1661Unexport all globals previously exported and 1662clear the environment inherited from the parent. 1663This operation will cause a memory leak of the original environment, 1664so should be used sparingly. 1665Testing for 1666.Va .MAKE.LEVEL 1667being 0, would make sense. 1668Also note that any variables which originated in the parent environment 1669should be explicitly preserved if desired. 1670For example: 1671.Bd -literal -offset indent 1672.Li .if ${.MAKE.LEVEL} == 0 1673PATH := ${PATH} 1674.Li .unexport-env 1675.Li .export PATH 1676.Li .endif 1677.Ed 1678.Pp 1679Would result in an environment containing only 1680.Ql Ev PATH , 1681which is the minimal useful environment. 1682Actually 1683.Ql Ev .MAKE.LEVEL 1684will also be pushed into the new environment. 1685.It Ic .warning Ar message 1686The message prefixed by 1687.Ql Pa warning: 1688is printed along with the name of the makefile and line number. 1689.It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ... 1690Test the value of an expression. 1691.It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1692Test the value of a variable. 1693.It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1694Test the value of a variable. 1695.It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1696Test the target being built. 1697.It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ... 1698Test the target being built. 1699.It Ic .else 1700Reverse the sense of the last conditional. 1701.It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ... 1702A combination of 1703.Ql Ic .else 1704followed by 1705.Ql Ic .if . 1706.It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1707A combination of 1708.Ql Ic .else 1709followed by 1710.Ql Ic .ifdef . 1711.It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1712A combination of 1713.Ql Ic .else 1714followed by 1715.Ql Ic .ifndef . 1716.It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1717A combination of 1718.Ql Ic .else 1719followed by 1720.Ql Ic .ifmake . 1721.It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1722A combination of 1723.Ql Ic .else 1724followed by 1725.Ql Ic .ifnmake . 1726.It Ic .endif 1727End the body of the conditional. 1728.El 1729.Pp 1730The 1731.Ar operator 1732may be any one of the following: 1733.Bl -tag -width "Cm XX" 1734.It Cm \&|\&| 1735Logical OR. 1736.It Cm \&\*[Am]\*[Am] 1737Logical 1738.Tn AND ; 1739of higher precedence than 1740.Dq \&|\&| . 1741.El 1742.Pp 1743As in C, 1744.Nm 1745will only evaluate a conditional as far as is necessary to determine 1746its value. 1747Parentheses may be used to change the order of evaluation. 1748The boolean operator 1749.Ql Ic \&! 1750may be used to logically negate an entire 1751conditional. 1752It is of higher precedence than 1753.Ql Ic \&\*[Am]\*[Am] . 1754.Pp 1755The value of 1756.Ar expression 1757may be any of the following: 1758.Bl -tag -width defined 1759.It Ic defined 1760Takes a variable name as an argument and evaluates to true if the variable 1761has been defined. 1762.It Ic make 1763Takes a target name as an argument and evaluates to true if the target 1764was specified as part of 1765.Nm Ns 's 1766command line or was declared the default target (either implicitly or 1767explicitly, see 1768.Va .MAIN ) 1769before the line containing the conditional. 1770.It Ic empty 1771Takes a variable, with possible modifiers, and evaluates to true if 1772the expansion of the variable would result in an empty string. 1773.It Ic exists 1774Takes a file name as an argument and evaluates to true if the file exists. 1775The file is searched for on the system search path (see 1776.Va .PATH ) . 1777.It Ic target 1778Takes a target name as an argument and evaluates to true if the target 1779has been defined. 1780.It Ic commands 1781Takes a target name as an argument and evaluates to true if the target 1782has been defined and has commands associated with it. 1783.El 1784.Pp 1785.Ar Expression 1786may also be an arithmetic or string comparison. 1787Variable expansion is 1788performed on both sides of the comparison, after which the integral 1789values are compared. 1790A value is interpreted as hexadecimal if it is 1791preceded by 0x, otherwise it is decimal; octal numbers are not supported. 1792The standard C relational operators are all supported. 1793If after 1794variable expansion, either the left or right hand side of a 1795.Ql Ic == 1796or 1797.Ql Ic "!=" 1798operator is not an integral value, then 1799string comparison is performed between the expanded 1800variables. 1801If no relational operator is given, it is assumed that the expanded 1802variable is being compared against 0 or an empty string in the case 1803of a string comparison. 1804.Pp 1805When 1806.Nm 1807is evaluating one of these conditional expressions, and it encounters 1808a (white-space separated) word it doesn't recognize, either the 1809.Dq make 1810or 1811.Dq defined 1812expression is applied to it, depending on the form of the conditional. 1813If the form is 1814.Ql Ic .ifdef , 1815.Ql Ic .ifndef , 1816or 1817.Ql Ic .if 1818the 1819.Dq defined 1820expression is applied. 1821Similarly, if the form is 1822.Ql Ic .ifmake 1823or 1824.Ql Ic .ifnmake , the 1825.Dq make 1826expression is applied. 1827.Pp 1828If the conditional evaluates to true the parsing of the makefile continues 1829as before. 1830If it evaluates to false, the following lines are skipped. 1831In both cases this continues until a 1832.Ql Ic .else 1833or 1834.Ql Ic .endif 1835is found. 1836.Pp 1837For loops are typically used to apply a set of rules to a list of files. 1838The syntax of a for loop is: 1839.Pp 1840.Bl -tag -compact -width Ds 1841.It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression 1842.It Aq make-rules 1843.It Ic \&.endfor 1844.El 1845.Pp 1846After the for 1847.Ic expression 1848is evaluated, it is split into words. 1849On each iteration of the loop, one word is taken and assigned to each 1850.Ic variable , 1851in order, and these 1852.Ic variables 1853are substituted into the 1854.Ic make-rules 1855inside the body of the for loop. 1856The number of words must come out even; that is, if there are three 1857iteration variables, the number of words provided must be a multiple 1858of three. 1859.Sh COMMENTS 1860Comments begin with a hash 1861.Pq Ql \&# 1862character, anywhere but in a shell 1863command line, and continue to the end of an unescaped new line. 1864.Sh SPECIAL SOURCES (ATTRIBUTES) 1865.Bl -tag -width .IGNOREx 1866.It Ic .EXEC 1867Target is never out of date, but always execute commands anyway. 1868.It Ic .IGNORE 1869Ignore any errors from the commands associated with this target, exactly 1870as if they all were preceded by a dash 1871.Pq Ql \- . 1872.\" .It Ic .INVISIBLE 1873.\" XXX 1874.\" .It Ic .JOIN 1875.\" XXX 1876.It Ic .MADE 1877Mark all sources of this target as being up-to-date. 1878.It Ic .MAKE 1879Execute the commands associated with this target even if the 1880.Fl n 1881or 1882.Fl t 1883options were specified. 1884Normally used to mark recursive 1885.Nm Ns s . 1886.It Ic .META 1887Create a meta file for the target, even if it is flagged as 1888.Ic .PHONY , 1889.Ic .MAKE , 1890or 1891.Ic .SPECIAL . 1892Usage in conjunction with 1893.Ic .MAKE 1894is the most likely case. 1895In "meta" mode, the target is out-of-date if the meta file is missing. 1896.It Ic .NOMETA 1897Do not create a meta file for the target. 1898Meta files are also not created for 1899.Ic .PHONY , 1900.Ic .MAKE , 1901or 1902.Ic .SPECIAL 1903targets. 1904.It Ic .NOMETA_CMP 1905Ignore differences in commands when deciding if target is out of date. 1906This is useful if the command contains a value which always changes. 1907If the number of commands change, though, the target will still be out of date. 1908The same effect applies to any command line that uses the variable 1909.Va .OODATE , 1910which can be used for that purpose even when not otherwise needed or desired: 1911.Bd -literal -offset indent 1912 1913skip-compare-for-some: 1914 @echo this will be compared 1915 @echo this will not ${.OODATE:M.NOMETA_CMP} 1916 @echo this will also be compared 1917 1918.Ed 1919The 1920.Cm \&:M 1921pattern suppresses any expansion of the unwanted variable. 1922.It Ic .NOPATH 1923Do not search for the target in the directories specified by 1924.Ic .PATH . 1925.It Ic .NOTMAIN 1926Normally 1927.Nm 1928selects the first target it encounters as the default target to be built 1929if no target was specified. 1930This source prevents this target from being selected. 1931.It Ic .OPTIONAL 1932If a target is marked with this attribute and 1933.Nm 1934can't figure out how to create it, it will ignore this fact and assume 1935the file isn't needed or already exists. 1936.It Ic .PHONY 1937The target does not 1938correspond to an actual file; it is always considered to be out of date, 1939and will not be created with the 1940.Fl t 1941option. 1942Suffix-transformation rules are not applied to 1943.Ic .PHONY 1944targets. 1945.It Ic .PRECIOUS 1946When 1947.Nm 1948is interrupted, it normally removes any partially made targets. 1949This source prevents the target from being removed. 1950.It Ic .RECURSIVE 1951Synonym for 1952.Ic .MAKE . 1953.It Ic .SILENT 1954Do not echo any of the commands associated with this target, exactly 1955as if they all were preceded by an at sign 1956.Pq Ql @ . 1957.It Ic .USE 1958Turn the target into 1959.Nm Ns 's 1960version of a macro. 1961When the target is used as a source for another target, the other target 1962acquires the commands, sources, and attributes (except for 1963.Ic .USE ) 1964of the 1965source. 1966If the target already has commands, the 1967.Ic .USE 1968target's commands are appended 1969to them. 1970.It Ic .USEBEFORE 1971Exactly like 1972.Ic .USE , 1973but prepend the 1974.Ic .USEBEFORE 1975target commands to the target. 1976.It Ic .WAIT 1977If 1978.Ic .WAIT 1979appears in a dependency line, the sources that precede it are 1980made before the sources that succeed it in the line. 1981Since the dependents of files are not made until the file itself 1982could be made, this also stops the dependents being built unless they 1983are needed for another branch of the dependency tree. 1984So given: 1985.Bd -literal 1986x: a .WAIT b 1987 echo x 1988a: 1989 echo a 1990b: b1 1991 echo b 1992b1: 1993 echo b1 1994 1995.Ed 1996the output is always 1997.Ql a , 1998.Ql b1 , 1999.Ql b , 2000.Ql x . 2001.br 2002The ordering imposed by 2003.Ic .WAIT 2004is only relevant for parallel makes. 2005.El 2006.Sh SPECIAL TARGETS 2007Special targets may not be included with other targets, i.e. they must be 2008the only target specified. 2009.Bl -tag -width .BEGINx 2010.It Ic .BEGIN 2011Any command lines attached to this target are executed before anything 2012else is done. 2013.It Ic .DEFAULT 2014This is sort of a 2015.Ic .USE 2016rule for any target (that was used only as a 2017source) that 2018.Nm 2019can't figure out any other way to create. 2020Only the shell script is used. 2021The 2022.Ic .IMPSRC 2023variable of a target that inherits 2024.Ic .DEFAULT Ns 's 2025commands is set 2026to the target's own name. 2027.It Ic .END 2028Any command lines attached to this target are executed after everything 2029else is done. 2030.It Ic .ERROR 2031Any command lines attached to this target are executed when another target fails. 2032The 2033.Ic .ERROR_TARGET 2034variable is set to the target that failed. 2035See also 2036.Ic MAKE_PRINT_VAR_ON_ERROR . 2037.It Ic .IGNORE 2038Mark each of the sources with the 2039.Ic .IGNORE 2040attribute. 2041If no sources are specified, this is the equivalent of specifying the 2042.Fl i 2043option. 2044.It Ic .INTERRUPT 2045If 2046.Nm 2047is interrupted, the commands for this target will be executed. 2048.It Ic .MAIN 2049If no target is specified when 2050.Nm 2051is invoked, this target will be built. 2052.It Ic .MAKEFLAGS 2053This target provides a way to specify flags for 2054.Nm 2055when the makefile is used. 2056The flags are as if typed to the shell, though the 2057.Fl f 2058option will have 2059no effect. 2060.\" XXX: NOT YET!!!! 2061.\" .It Ic .NOTPARALLEL 2062.\" The named targets are executed in non parallel mode. 2063.\" If no targets are 2064.\" specified, then all targets are executed in non parallel mode. 2065.It Ic .NOPATH 2066Apply the 2067.Ic .NOPATH 2068attribute to any specified sources. 2069.It Ic .NOTPARALLEL 2070Disable parallel mode. 2071.It Ic .NO_PARALLEL 2072Synonym for 2073.Ic .NOTPARALLEL , 2074for compatibility with other pmake variants. 2075.It Ic .OBJDIR 2076The source is a new value for 2077.Ql Va .OBJDIR . 2078If it exists, 2079.Nm 2080will 2081.Xr chdir 2 2082to it and update the value of 2083.Ql Va .OBJDIR . 2084.It Ic .ORDER 2085The named targets are made in sequence. 2086This ordering does not add targets to the list of targets to be made. 2087Since the dependents of a target do not get built until the target itself 2088could be built, unless 2089.Ql a 2090is built by another part of the dependency graph, 2091the following is a dependency loop: 2092.Bd -literal 2093\&.ORDER: b a 2094b: a 2095.Ed 2096.Pp 2097The ordering imposed by 2098.Ic .ORDER 2099is only relevant for parallel makes. 2100.\" XXX: NOT YET!!!! 2101.\" .It Ic .PARALLEL 2102.\" The named targets are executed in parallel mode. 2103.\" If no targets are 2104.\" specified, then all targets are executed in parallel mode. 2105.It Ic .PATH 2106The sources are directories which are to be searched for files not 2107found in the current directory. 2108If no sources are specified, any previously specified directories are 2109deleted. 2110If the source is the special 2111.Ic .DOTLAST 2112target, then the current working 2113directory is searched last. 2114.It Ic .PATH. Ns Va suffix 2115Like 2116.Ic .PATH 2117but applies only to files with a particular suffix. 2118The suffix must have been previously declared with 2119.Ic .SUFFIXES . 2120.It Ic .PHONY 2121Apply the 2122.Ic .PHONY 2123attribute to any specified sources. 2124.It Ic .PRECIOUS 2125Apply the 2126.Ic .PRECIOUS 2127attribute to any specified sources. 2128If no sources are specified, the 2129.Ic .PRECIOUS 2130attribute is applied to every 2131target in the file. 2132.It Ic .SHELL 2133Sets the shell that 2134.Nm 2135will use to execute commands. 2136The sources are a set of 2137.Ar field=value 2138pairs. 2139.Bl -tag -width hasErrCtls 2140.It Ar name 2141This is the minimal specification, used to select one of the built-in 2142shell specs; 2143.Ar sh , 2144.Ar ksh , 2145and 2146.Ar csh . 2147.It Ar path 2148Specifies the path to the shell. 2149.It Ar hasErrCtl 2150Indicates whether the shell supports exit on error. 2151.It Ar check 2152The command to turn on error checking. 2153.It Ar ignore 2154The command to disable error checking. 2155.It Ar echo 2156The command to turn on echoing of commands executed. 2157.It Ar quiet 2158The command to turn off echoing of commands executed. 2159.It Ar filter 2160The output to filter after issuing the 2161.Ar quiet 2162command. 2163It is typically identical to 2164.Ar quiet . 2165.It Ar errFlag 2166The flag to pass the shell to enable error checking. 2167.It Ar echoFlag 2168The flag to pass the shell to enable command echoing. 2169.It Ar newline 2170The string literal to pass the shell that results in a single newline 2171character when used outside of any quoting characters. 2172.El 2173Example: 2174.Bd -literal 2175\&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e 2176 check="set \-e" ignore="set +e" \e 2177 echo="set \-v" quiet="set +v" filter="set +v" \e 2178 echoFlag=v errFlag=e newline="'\en'" 2179.Ed 2180.It Ic .SILENT 2181Apply the 2182.Ic .SILENT 2183attribute to any specified sources. 2184If no sources are specified, the 2185.Ic .SILENT 2186attribute is applied to every 2187command in the file. 2188.It Ic .STALE 2189This target gets run when a dependency file contains stale entries, having 2190.Va .ALLSRC 2191set to the name of that dependency file. 2192.It Ic .SUFFIXES 2193Each source specifies a suffix to 2194.Nm . 2195If no sources are specified, any previously specified suffixes are deleted. 2196It allows the creation of suffix-transformation rules. 2197.Pp 2198Example: 2199.Bd -literal 2200\&.SUFFIXES: .o 2201\&.c.o: 2202 cc \-o ${.TARGET} \-c ${.IMPSRC} 2203.Ed 2204.El 2205.Sh ENVIRONMENT 2206.Nm 2207uses the following environment variables, if they exist: 2208.Ev MACHINE , 2209.Ev MACHINE_ARCH , 2210.Ev MAKE , 2211.Ev MAKEFLAGS , 2212.Ev MAKEOBJDIR , 2213.Ev MAKEOBJDIRPREFIX , 2214.Ev MAKESYSPATH , 2215.Ev PWD , 2216and 2217.Ev TMPDIR . 2218.Pp 2219.Ev MAKEOBJDIRPREFIX 2220and 2221.Ev MAKEOBJDIR 2222may only be set in the environment or on the command line to 2223.Nm 2224and not as makefile variables; 2225see the description of 2226.Ql Va .OBJDIR 2227for more details. 2228.Sh FILES 2229.Bl -tag -width /usr/share/mk -compact 2230.It .depend 2231list of dependencies 2232.It Makefile 2233list of dependencies 2234.It makefile 2235list of dependencies 2236.It sys.mk 2237system makefile 2238.It /usr/share/mk 2239system makefile directory 2240.El 2241.Sh COMPATIBILITY 2242The basic make syntax is compatible between different versions of make; 2243however the special variables, variable modifiers and conditionals are not. 2244.Ss Older versions 2245An incomplete list of changes in older versions of 2246.Nm : 2247.Pp 2248The way that .for loop variables are substituted changed after 2249NetBSD 5.0 2250so that they still appear to be variable expansions. 2251In particular this stops them being treated as syntax, and removes some 2252obscure problems using them in .if statements. 2253.Pp 2254The way that parallel makes are scheduled changed in 2255NetBSD 4.0 2256so that .ORDER and .WAIT apply recursively to the dependent nodes. 2257The algorithms used may change again in the future. 2258.Ss Other make dialects 2259Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not 2260support most of the features of 2261.Nm 2262as described in this manual. 2263Most notably: 2264.Bl -bullet -offset indent 2265.It 2266The 2267.Ic .WAIT 2268and 2269.Ic .ORDER 2270declarations and most functionality pertaining to parallelization. 2271(GNU make supports parallelization but lacks these features needed to 2272control it effectively.) 2273.It 2274Directives, including for loops and conditionals and most of the 2275forms of include files. 2276(GNU make has its own incompatible and less powerful syntax for 2277conditionals.) 2278.It 2279All built-in variables that begin with a dot. 2280.It 2281Most of the special sources and targets that begin with a dot, 2282with the notable exception of 2283.Ic .PHONY , 2284.Ic .PRECIOUS , 2285and 2286.Ic .SUFFIXES . 2287.It 2288Variable modifiers, except for the 2289.Dl :old=new 2290string substitution, which does not portably support globbing with 2291.Ql % 2292and historically only works on declared suffixes. 2293.It 2294The 2295.Ic $> 2296variable even in its short form; most makes support this functionality 2297but its name varies. 2298.El 2299.Pp 2300Some features are somewhat more portable, such as assignment with 2301.Ic += , 2302.Ic ?= , 2303and 2304.Ic != . 2305The 2306.Ic .PATH 2307functionality is based on an older feature 2308.Ic VPATH 2309found in GNU make and many versions of SVR4 make; however, 2310historically its behavior is too ill-defined (and too buggy) to rely 2311upon. 2312.Pp 2313The 2314.Ic $@ 2315and 2316.Ic $< 2317variables are more or less universally portable, as is the 2318.Ic $(MAKE) 2319variable. 2320Basic use of suffix rules (for files only in the current directory, 2321not trying to chain transformations together, etc.) is also reasonably 2322portable. 2323.Sh SEE ALSO 2324.Xr mkdep 1 2325.Sh HISTORY 2326.Nm 2327is derived from NetBSD 2328.Xr make 1 . 2329It uses autoconf to facilitate portability to other platforms. 2330.Pp 2331A 2332make 2333command appeared in 2334.At v7 . 2335This 2336make 2337implementation is based on Adam De Boor's pmake program which was written 2338for Sprite at Berkeley. 2339It was designed to be a parallel distributed make running jobs on different 2340machines using a daemon called 2341.Dq customs . 2342.Pp 2343Historically the target/dependency 2344.Dq FRC 2345has been used to FoRCe rebuilding (since the target/dependency 2346does not exist... unless someone creates an 2347.Dq FRC 2348file). 2349.Sh BUGS 2350The 2351make 2352syntax is difficult to parse without actually acting of the data. 2353For instance finding the end of a variable use should involve scanning each 2354the modifiers using the correct terminator for each field. 2355In many places 2356make 2357just counts {} and () in order to find the end of a variable expansion. 2358.Pp 2359There is no way of escaping a space character in a filename. 2360