1.\" $NetBSD: make.1,v 1.272 2018/04/02 04:26:17 dholland 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 June 22, 2017 33.Dt MAKE 1 34.Os 35.Sh NAME 36.Nm make 37.Nd maintain program dependencies 38.Sh SYNOPSIS 39.Nm 40.Op Fl BeikNnqrstWwX 41.Op Fl C Ar directory 42.Op Fl D Ar variable 43.Op Fl d Ar flags 44.Op Fl f Ar makefile 45.Op Fl I Ar directory 46.Op Fl J Ar private 47.Op Fl j Ar max_jobs 48.Op Fl m Ar directory 49.Op Fl T Ar file 50.Op Fl V Ar variable 51.Op Fl v Ar variable 52.Op Ar variable=value 53.Op Ar target ... 54.Sh DESCRIPTION 55.Nm 56is a program designed to simplify the maintenance of other programs. 57Its input is a list of specifications as to the files upon which programs 58and other files depend. 59If no 60.Fl f Ar makefile 61makefile option is given, 62.Nm 63will try to open 64.Ql Pa makefile 65then 66.Ql Pa Makefile 67in order to find the specifications. 68If the file 69.Ql Pa .depend 70exists, it is read (see 71.Xr mkdep 1 ) . 72.Pp 73This manual page is intended as a reference document only. 74For a more thorough description of 75.Nm 76and makefiles, please refer to 77.%T "PMake \- A Tutorial" . 78.Pp 79.Nm 80will prepend the contents of the 81.Va MAKEFLAGS 82environment variable to the command line arguments before parsing them. 83.Pp 84The options are as follows: 85.Bl -tag -width Ds 86.It Fl B 87Try to be backwards compatible by executing a single shell per command and 88by executing the commands to make the sources of a dependency line in sequence. 89.It Fl C Ar directory 90Change to 91.Ar directory 92before reading the makefiles or doing anything else. 93If multiple 94.Fl C 95options are specified, each is interpreted relative to the previous one: 96.Fl C Pa / Fl C Pa etc 97is equivalent to 98.Fl C Pa /etc . 99.It Fl D Ar variable 100Define 101.Ar variable 102to be 1, in the global context. 103.It Fl d Ar [-]flags 104Turn on debugging, and specify which portions of 105.Nm 106are to print debugging information. 107Unless the flags are preceded by 108.Ql \- 109they are added to the 110.Va MAKEFLAGS 111environment variable and will be processed by any child make processes. 112By default, debugging information is printed to standard error, 113but this can be changed using the 114.Ar F 115debugging flag. 116The debugging output is always unbuffered; in addition, if debugging 117is enabled but debugging output is not directed to standard output, 118then the standard output is line buffered. 119.Ar Flags 120is one or more of the following: 121.Bl -tag -width Ds 122.It Ar A 123Print all possible debugging information; 124equivalent to specifying all of the debugging flags. 125.It Ar a 126Print debugging information about archive searching and caching. 127.It Ar C 128Print debugging information about current working directory. 129.It Ar c 130Print debugging information about conditional evaluation. 131.It Ar d 132Print debugging information about directory searching and caching. 133.It Ar e 134Print debugging information about failed commands and targets. 135.It Ar F Ns Oo Sy \&+ Oc Ns Ar filename 136Specify where debugging output is written. 137This must be the last flag, because it consumes the remainder of 138the argument. 139If the character immediately after the 140.Ql F 141flag is 142.Ql \&+ , 143then the file will be opened in append mode; 144otherwise the file will be overwritten. 145If the file name is 146.Ql stdout 147or 148.Ql stderr 149then debugging output will be written to the 150standard output or standard error output file descriptors respectively 151(and the 152.Ql \&+ 153option has no effect). 154Otherwise, the output will be written to the named file. 155If the file name ends 156.Ql .%d 157then the 158.Ql %d 159is replaced by the pid. 160.It Ar f 161Print debugging information about loop evaluation. 162.It Ar "g1" 163Print the input graph before making anything. 164.It Ar "g2" 165Print the input graph after making everything, or before exiting 166on error. 167.It Ar "g3" 168Print the input graph before exiting on error. 169.It Ar j 170Print debugging information about running multiple shells. 171.It Ar l 172Print commands in Makefiles regardless of whether or not they are prefixed by 173.Ql @ 174or other "quiet" flags. 175Also known as "loud" behavior. 176.It Ar M 177Print debugging information about "meta" mode decisions about targets. 178.It Ar m 179Print debugging information about making targets, including modification 180dates. 181.It Ar n 182Don't delete the temporary command scripts created when running commands. 183These temporary scripts are created in the directory 184referred to by the 185.Ev TMPDIR 186environment variable, or in 187.Pa /tmp 188if 189.Ev TMPDIR 190is unset or set to the empty string. 191The temporary scripts are created by 192.Xr mkstemp 3 , 193and have names of the form 194.Pa makeXXXXXX . 195.Em NOTE : 196This can create many files in 197.Ev TMPDIR 198or 199.Pa /tmp , 200so use with care. 201.It Ar p 202Print debugging information about makefile parsing. 203.It Ar s 204Print debugging information about suffix-transformation rules. 205.It Ar t 206Print debugging information about target list maintenance. 207.It Ar V 208Force the 209.Fl V 210option to print raw values of variables, overriding the default behavior 211set via 212.Va .MAKE.EXPAND_VARIABLES . 213.It Ar v 214Print debugging information about variable assignment. 215.It Ar x 216Run shell commands with 217.Fl x 218so the actual commands are printed as they are executed. 219.El 220.It Fl e 221Specify that environment variables override macro assignments within 222makefiles. 223.It Fl f Ar makefile 224Specify a makefile to read instead of the default 225.Ql Pa makefile . 226If 227.Ar makefile 228is 229.Ql Fl , 230standard input is read. 231Multiple makefiles may be specified, and are read in the order specified. 232.It Fl I Ar directory 233Specify a directory in which to search for makefiles and included makefiles. 234The system makefile directory (or directories, see the 235.Fl m 236option) is automatically included as part of this list. 237.It Fl i 238Ignore non-zero exit of shell commands in the makefile. 239Equivalent to specifying 240.Ql Fl 241before each command line in the makefile. 242.It Fl J Ar private 243This option should 244.Em not 245be specified by the user. 246.Pp 247When the 248.Ar j 249option is in use in a recursive build, this option is passed by a make 250to child makes to allow all the make processes in the build to 251cooperate to avoid overloading the system. 252.It Fl j Ar max_jobs 253Specify the maximum number of jobs that 254.Nm 255may have running at any one time. 256The value is saved in 257.Va .MAKE.JOBS . 258Turns compatibility mode off, unless the 259.Ar B 260flag is also specified. 261When compatibility mode is off, all commands associated with a 262target are executed in a single shell invocation as opposed to the 263traditional one shell invocation per line. 264This can break traditional scripts which change directories on each 265command invocation and then expect to start with a fresh environment 266on the next line. 267It is more efficient to correct the scripts rather than turn backwards 268compatibility on. 269.It Fl k 270Continue processing after errors are encountered, but only on those targets 271that do not depend on the target whose creation caused the error. 272.It Fl m Ar directory 273Specify a directory in which to search for sys.mk and makefiles included 274via the 275.Ao Ar file Ac Ns -style 276include statement. 277The 278.Fl m 279option can be used multiple times to form a search path. 280This path will override the default system include path: /usr/share/mk. 281Furthermore the system include path will be appended to the search path used 282for 283.Qo Ar file Qc Ns -style 284include statements (see the 285.Fl I 286option). 287.Pp 288If a file or directory name in the 289.Fl m 290argument (or the 291.Ev MAKESYSPATH 292environment variable) starts with the string 293.Qq \&.../ 294then 295.Nm 296will search for the specified file or directory named in the remaining part 297of the argument string. 298The search starts with the current directory of 299the Makefile and then works upward towards the root of the file system. 300If the search is successful, then the resulting directory replaces the 301.Qq \&.../ 302specification in the 303.Fl m 304argument. 305If used, this feature allows 306.Nm 307to easily search in the current source tree for customized sys.mk files 308(e.g., by using 309.Qq \&.../mk/sys.mk 310as an argument). 311.It Fl n 312Display the commands that would have been executed, but do not 313actually execute them unless the target depends on the .MAKE special 314source (see below). 315.It Fl N 316Display the commands which would have been executed, but do not 317actually execute any of them; useful for debugging top-level makefiles 318without descending into subdirectories. 319.It Fl q 320Do not execute any commands, but exit 0 if the specified targets are 321up-to-date and 1, otherwise. 322.It Fl r 323Do not use the built-in rules specified in the system makefile. 324.It Fl s 325Do not echo any commands as they are executed. 326Equivalent to specifying 327.Ql Ic @ 328before each command line in the makefile. 329.It Fl T Ar tracefile 330When used with the 331.Fl j 332flag, 333append a trace record to 334.Ar tracefile 335for each job started and completed. 336.It Fl t 337Rather than re-building a target as specified in the makefile, create it 338or update its modification time to make it appear up-to-date. 339.It Fl V Ar variable 340Print the value of 341.Ar variable . 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. 346The value printed is extracted from the global context after all 347makefiles have been read. 348By default, the raw variable contents (which may 349include additional unexpanded variable references) are shown. 350If 351.Ar variable 352contains a 353.Ql \&$ 354then the value will be recursively expanded to its complete resultant 355text before printing. 356The expanded value will also be printed if 357.Va .MAKE.EXPAND_VARIABLES 358is set to true and 359the 360.Fl dV 361option has not been used to override it. 362Note that loop-local and target-local variables, as well as values 363taken temporarily by global variables during makefile processing, are 364not accessible via this option. 365The 366.Fl dv 367debug mode can be used to see these at the cost of generating 368substantial extraneous output. 369.It Fl v Ar variable 370Like 371.Fl V 372but the variable is always expanded to its complete value. 373.It Fl W 374Treat any warnings during makefile parsing as errors. 375.It Fl w 376Print entering and leaving directory messages, pre and post processing. 377.It Fl X 378Don't export variables passed on the command line to the environment 379individually. 380Variables passed on the command line are still exported 381via the 382.Va MAKEFLAGS 383environment variable. 384This option may be useful on systems which have a small limit on the 385size of command arguments. 386.It Ar variable=value 387Set the value of the variable 388.Ar variable 389to 390.Ar value . 391Normally, all values passed on the command line are also exported to 392sub-makes in the environment. 393The 394.Fl X 395flag disables this behavior. 396Variable assignments should follow options for POSIX compatibility 397but no ordering is enforced. 398.El 399.Pp 400There are seven different types of lines in a makefile: file dependency 401specifications, shell commands, variable assignments, include statements, 402conditional directives, for loops, and comments. 403.Pp 404In general, lines may be continued from one line to the next by ending 405them with a backslash 406.Pq Ql \e . 407The trailing newline character and initial whitespace on the following 408line are compressed into a single space. 409.Sh FILE DEPENDENCY SPECIFICATIONS 410Dependency lines consist of one or more targets, an operator, and zero 411or more sources. 412This creates a relationship where the targets 413.Dq depend 414on the sources 415and are usually created from them. 416The exact relationship between the target and the source is determined 417by the operator that separates them. 418The three operators are as follows: 419.Bl -tag -width flag 420.It Ic \&: 421A target is considered out-of-date if its modification time is less than 422those of any of its sources. 423Sources for a target accumulate over dependency lines when this operator 424is used. 425The target is removed if 426.Nm 427is interrupted. 428.It Ic \&! 429Targets are always re-created, but not until all sources have been 430examined and re-created as necessary. 431Sources for a target accumulate over dependency lines when this operator 432is used. 433The target is removed if 434.Nm 435is interrupted. 436.It Ic \&:: 437If no sources are specified, the target is always re-created. 438Otherwise, a target is considered out-of-date if any of its sources has 439been modified more recently than the target. 440Sources for a target do not accumulate over dependency lines when this 441operator is used. 442The target will not be removed if 443.Nm 444is interrupted. 445.El 446.Pp 447Targets and sources may contain the shell wildcard values 448.Ql \&? , 449.Ql * , 450.Ql [] , 451and 452.Ql {} . 453The values 454.Ql \&? , 455.Ql * , 456and 457.Ql [] 458may only be used as part of the final 459component of the target or source, and must be used to describe existing 460files. 461The value 462.Ql {} 463need not necessarily be used to describe existing files. 464Expansion is in directory order, not alphabetically as done in the shell. 465.Sh SHELL COMMANDS 466Each target may have associated with it one or more lines of shell 467commands, normally 468used to create the target. 469Each of the lines in this script 470.Em must 471be preceded by a tab. 472(For historical reasons, spaces are not accepted.) 473While targets can appear in many dependency lines if desired, by 474default only one of these rules may be followed by a creation 475script. 476If the 477.Ql Ic \&:: 478operator is used, however, all rules may include scripts and the 479scripts are executed in the order found. 480.Pp 481Each line is treated as a separate shell command, unless the end of 482line is escaped with a backslash 483.Pq Ql \e 484in which case that line and the next are combined. 485.\" The escaped newline is retained and passed to the shell, which 486.\" normally ignores it. 487.\" However, the tab at the beginning of the following line is removed. 488If the first characters of the command are any combination of 489.Ql Ic @ , 490.Ql Ic + , 491or 492.Ql Ic \- , 493the command is treated specially. 494A 495.Ql Ic @ 496causes the command not to be echoed before it is executed. 497A 498.Ql Ic + 499causes the command to be executed even when 500.Fl n 501is given. 502This is similar to the effect of the .MAKE special source, 503except that the effect can be limited to a single line of a script. 504A 505.Ql Ic \- 506in compatibility mode 507causes any non-zero exit status of the command line to be ignored. 508.Pp 509When 510.Nm 511is run in jobs mode with 512.Fl j Ar max_jobs , 513the entire script for the target is fed to a 514single instance of the shell. 515In compatibility (non-jobs) mode, each command is run in a separate process. 516If the command contains any shell meta characters 517.Pq Ql #=|^(){};&<>*?[]:$`\e\en 518it will be passed to the shell; otherwise 519.Nm 520will attempt direct execution. 521If a line starts with 522.Ql Ic \- 523and the shell has ErrCtl enabled then failure of the command line 524will be ignored as in compatibility mode. 525Otherwise 526.Ql Ic \- 527affects the entire job; 528the script will stop at the first command line that fails, 529but the target will not be deemed to have failed. 530.Pp 531Makefiles should be written so that the mode of 532.Nm 533operation does not change their behavior. 534For example, any command which needs to use 535.Dq cd 536or 537.Dq chdir 538without potentially changing the directory for subsequent commands 539should be put in parentheses so it executes in a subshell. 540To force the use of one shell, escape the line breaks so as to make 541the whole script one command. 542For example: 543.Bd -literal -offset indent 544avoid-chdir-side-effects: 545 @echo Building $@ in `pwd` 546 @(cd ${.CURDIR} && ${MAKE} $@) 547 @echo Back in `pwd` 548 549ensure-one-shell-regardless-of-mode: 550 @echo Building $@ in `pwd`; \e 551 (cd ${.CURDIR} && ${MAKE} $@); \e 552 echo Back in `pwd` 553.Ed 554.Pp 555Since 556.Nm 557will 558.Xr chdir 2 559to 560.Ql Va .OBJDIR 561before executing any targets, each child process 562starts with that as its current working directory. 563.Sh VARIABLE ASSIGNMENTS 564Variables in make are much like variables in the shell, and, by tradition, 565consist of all upper-case letters. 566.Ss Variable assignment modifiers 567The five operators that can be used to assign values to variables are as 568follows: 569.Bl -tag -width Ds 570.It Ic \&= 571Assign the value to the variable. 572Any previous value is overridden. 573.It Ic \&+= 574Append the value to the current value of the variable. 575.It Ic \&?= 576Assign the value to the variable if it is not already defined. 577.It Ic \&:= 578Assign with expansion, i.e. expand the value before assigning it 579to the variable. 580Normally, expansion is not done until the variable is referenced. 581.Em NOTE : 582References to undefined variables are 583.Em not 584expanded. 585This can cause problems when variable modifiers are used. 586.It Ic \&!= 587Expand the value and pass it to the shell for execution and assign 588the result to the variable. 589Any newlines in the result are replaced with spaces. 590.El 591.Pp 592Any white-space before the assigned 593.Ar value 594is removed; if the value is being appended, a single space is inserted 595between the previous contents of the variable and the appended value. 596.Pp 597Variables are expanded by surrounding the variable name with either 598curly braces 599.Pq Ql {} 600or parentheses 601.Pq Ql () 602and preceding it with 603a dollar sign 604.Pq Ql \&$ . 605If the variable name contains only a single letter, the surrounding 606braces or parentheses are not required. 607This shorter form is not recommended. 608.Pp 609If the variable name contains a dollar, then the name itself is expanded first. 610This allows almost arbitrary variable names, however names containing dollar, 611braces, parenthesis, or whitespace are really best avoided! 612.Pp 613If the result of expanding a variable contains a dollar sign 614.Pq Ql \&$ 615the string is expanded again. 616.Pp 617Variable substitution occurs at three distinct times, depending on where 618the variable is being used. 619.Bl -enum 620.It 621Variables in dependency lines are expanded as the line is read. 622.It 623Variables in shell commands are expanded when the shell command is 624executed. 625.It 626.Dq .for 627loop index variables are expanded on each loop iteration. 628Note that other variables are not expanded inside loops so 629the following example code: 630.Bd -literal -offset indent 631 632.Dv .for i in 1 2 3 633a+= ${i} 634j= ${i} 635b+= ${j} 636.Dv .endfor 637 638all: 639 @echo ${a} 640 @echo ${b} 641 642.Ed 643will print: 644.Bd -literal -offset indent 6451 2 3 6463 3 3 647 648.Ed 649Because while ${a} contains 650.Dq 1 2 3 651after the loop is executed, ${b} 652contains 653.Dq ${j} ${j} ${j} 654which expands to 655.Dq 3 3 3 656since after the loop completes ${j} contains 657.Dq 3 . 658.El 659.Ss Variable classes 660The four different classes of variables (in order of increasing precedence) 661are: 662.Bl -tag -width Ds 663.It Environment variables 664Variables defined as part of 665.Nm Ns 's 666environment. 667.It Global variables 668Variables defined in the makefile or in included makefiles. 669.It Command line variables 670Variables defined as part of the command line. 671.It Local variables 672Variables that are defined specific to a certain target. 673.El 674.Pp 675Local variables are all built in and their values vary magically from 676target to target. 677It is not currently possible to define new local variables. 678The seven local variables are as follows: 679.Bl -tag -width ".ARCHIVE" -offset indent 680.It Va .ALLSRC 681The list of all sources for this target; also known as 682.Ql Va \&> . 683.It Va .ARCHIVE 684The name of the archive file; also known as 685.Ql Va \&! . 686.It Va .IMPSRC 687In suffix-transformation rules, the name/path of the source from which the 688target is to be transformed (the 689.Dq implied 690source); also known as 691.Ql Va \&< . 692It is not defined in explicit rules. 693.It Va .MEMBER 694The name of the archive member; also known as 695.Ql Va % . 696.It Va .OODATE 697The list of sources for this target that were deemed out-of-date; also 698known as 699.Ql Va \&? . 700.It Va .PREFIX 701The file prefix of the target, containing only the file portion, no suffix 702or preceding directory components; also known as 703.Ql Va * . 704The suffix must be one of the known suffixes declared with 705.Ic .SUFFIXES 706or it will not be recognized. 707.It Va .TARGET 708The name of the target; also known as 709.Ql Va @ . 710For compatibility with other makes this is an alias for 711.Ic .ARCHIVE 712in archive member rules. 713.El 714.Pp 715The shorter forms 716.Ql ( Va > , 717.Ql Va \&! , 718.Ql Va < , 719.Ql Va % , 720.Ql Va \&? , 721.Ql Va * , 722and 723.Ql Va @ ) 724are permitted for backward 725compatibility with historical makefiles and legacy POSIX make and are 726not recommended. 727.Pp 728Variants of these variables with the punctuation followed immediately by 729.Ql D 730or 731.Ql F , 732e.g. 733.Ql Va $(@D) , 734are legacy forms equivalent to using the 735.Ql :H 736and 737.Ql :T 738modifiers. 739These forms are accepted for compatibility with 740.At V 741makefiles and POSIX but are not recommended. 742.Pp 743Four of the local variables may be used in sources on dependency lines 744because they expand to the proper value for each target on the line. 745These variables are 746.Ql Va .TARGET , 747.Ql Va .PREFIX , 748.Ql Va .ARCHIVE , 749and 750.Ql Va .MEMBER . 751.Ss Additional built-in variables 752In addition, 753.Nm 754sets or knows about the following variables: 755.Bl -tag -width .MAKEOVERRIDES 756.It Va \&$ 757A single dollar sign 758.Ql \&$ , 759i.e. 760.Ql \&$$ 761expands to a single dollar 762sign. 763.It Va .ALLTARGETS 764The list of all targets encountered in the Makefile. 765If evaluated during 766Makefile parsing, lists only those targets encountered thus far. 767.It Va .CURDIR 768A path to the directory where 769.Nm 770was executed. 771Refer to the description of 772.Ql Ev PWD 773for more details. 774.It Va .INCLUDEDFROMDIR 775The directory of the file this Makefile was included from. 776.It Va .INCLUDEDFROMFILE 777The filename of the file this Makefile was included from. 778.It Ev MAKE 779The name that 780.Nm 781was executed with 782.Pq Va argv[0] . 783For compatibility 784.Nm 785also sets 786.Va .MAKE 787with the same value. 788The preferred variable to use is the environment variable 789.Ev MAKE 790because it is more compatible with other versions of 791.Nm 792and cannot be confused with the special target with the same name. 793.It Va .MAKE.DEPENDFILE 794Names the makefile (default 795.Ql Pa .depend ) 796from which generated dependencies are read. 797.It Va .MAKE.EXPAND_VARIABLES 798A boolean that controls the default behavior of the 799.Fl V 800option. 801If true, variable values printed with 802.Fl V 803are fully expanded; if false, the raw variable contents (which may 804include additional unexpanded variable references) are shown. 805.It Va .MAKE.EXPORTED 806The list of variables exported by 807.Nm . 808.It Va .MAKE.JOBS 809The argument to the 810.Fl j 811option. 812.It Va .MAKE.JOB.PREFIX 813If 814.Nm 815is run with 816.Ar j 817then output for each target is prefixed with a token 818.Ql --- target --- 819the first part of which can be controlled via 820.Va .MAKE.JOB.PREFIX . 821If 822.Va .MAKE.JOB.PREFIX 823is empty, no token is printed. 824.br 825For example: 826.Li .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}] 827would produce tokens like 828.Ql ---make[1234] target --- 829making it easier to track the degree of parallelism being achieved. 830.It Ev MAKEFLAGS 831The environment variable 832.Ql Ev MAKEFLAGS 833may contain anything that 834may be specified on 835.Nm Ns 's 836command line. 837Anything specified on 838.Nm Ns 's 839command line is appended to the 840.Ql Ev MAKEFLAGS 841variable which is then 842entered into the environment for all programs which 843.Nm 844executes. 845.It Va .MAKE.LEVEL 846The recursion depth of 847.Nm . 848The initial instance of 849.Nm 850will be 0, and an incremented value is put into the environment 851to be seen by the next generation. 852This allows tests like: 853.Li .if ${.MAKE.LEVEL} == 0 854to protect things which should only be evaluated in the initial instance of 855.Nm . 856.It Va .MAKE.MAKEFILE_PREFERENCE 857The ordered list of makefile names 858(default 859.Ql Pa makefile , 860.Ql Pa Makefile ) 861that 862.Nm 863will look for. 864.It Va .MAKE.MAKEFILES 865The list of makefiles read by 866.Nm , 867which is useful for tracking dependencies. 868Each makefile is recorded only once, regardless of the number of times read. 869.It Va .MAKE.MODE 870Processed after reading all makefiles. 871Can affect the mode that 872.Nm 873runs in. 874It can contain a number of keywords: 875.Bl -hang -width missing-filemon=bf. 876.It Pa compat 877Like 878.Fl B , 879puts 880.Nm 881into "compat" mode. 882.It Pa meta 883Puts 884.Nm 885into "meta" mode, where meta files are created for each target 886to capture the command run, the output generated and if 887.Xr filemon 4 888is available, the system calls which are of interest to 889.Nm . 890The captured output can be very useful when diagnosing errors. 891.It Pa curdirOk= Ar bf 892Normally 893.Nm 894will not create .meta files in 895.Ql Va .CURDIR . 896This can be overridden by setting 897.Va bf 898to a value which represents True. 899.It Pa missing-meta= Ar bf 900If 901.Va bf 902is True, then a missing .meta file makes the target out-of-date. 903.It Pa missing-filemon= Ar bf 904If 905.Va bf 906is True, then missing filemon data makes the target out-of-date. 907.It Pa nofilemon 908Do not use 909.Xr filemon 4 . 910.It Pa env 911For debugging, it can be useful to include the environment 912in the .meta file. 913.It Pa verbose 914If in "meta" mode, print a clue about the target being built. 915This is useful if the build is otherwise running silently. 916The message printed the value of: 917.Va .MAKE.META.PREFIX . 918.It Pa ignore-cmd 919Some makefiles have commands which are simply not stable. 920This keyword causes them to be ignored for 921determining whether a target is out of date in "meta" mode. 922See also 923.Ic .NOMETA_CMP . 924.It Pa silent= Ar bf 925If 926.Va bf 927is True, when a .meta file is created, mark the target 928.Ic .SILENT . 929.El 930.It Va .MAKE.META.BAILIWICK 931In "meta" mode, provides a list of prefixes which 932match the directories controlled by 933.Nm . 934If a file that was generated outside of 935.Va .OBJDIR 936but within said bailiwick is missing, 937the current target is considered out-of-date. 938.It Va .MAKE.META.CREATED 939In "meta" mode, this variable contains a list of all the meta files 940updated. 941If not empty, it can be used to trigger processing of 942.Va .MAKE.META.FILES . 943.It Va .MAKE.META.FILES 944In "meta" mode, this variable contains a list of all the meta files 945used (updated or not). 946This list can be used to process the meta files to extract dependency 947information. 948.It Va .MAKE.META.IGNORE_PATHS 949Provides a list of path prefixes that should be ignored; 950because the contents are expected to change over time. 951The default list includes: 952.Ql Pa /dev /etc /proc /tmp /var/run /var/tmp 953.It Va .MAKE.META.IGNORE_PATTERNS 954Provides a list of patterns to match against pathnames. 955Ignore any that match. 956.It Va .MAKE.META.IGNORE_FILTER 957Provides a list of variable modifiers to apply to each pathname. 958Ignore if the expansion is an empty string. 959.It Va .MAKE.META.PREFIX 960Defines the message printed for each meta file updated in "meta verbose" mode. 961The default value is: 962.Dl Building ${.TARGET:H:tA}/${.TARGET:T} 963.It Va .MAKEOVERRIDES 964This variable is used to record the names of variables assigned to 965on the command line, so that they may be exported as part of 966.Ql Ev MAKEFLAGS . 967This behavior can be disabled by assigning an empty value to 968.Ql Va .MAKEOVERRIDES 969within a makefile. 970Extra variables can be exported from a makefile 971by appending their names to 972.Ql Va .MAKEOVERRIDES . 973.Ql Ev MAKEFLAGS 974is re-exported whenever 975.Ql Va .MAKEOVERRIDES 976is modified. 977.It Va .MAKE.PATH_FILEMON 978If 979.Nm 980was built with 981.Xr filemon 4 982support, this is set to the path of the device node. 983This allows makefiles to test for this support. 984.It Va .MAKE.PID 985The process-id of 986.Nm . 987.It Va .MAKE.PPID 988The parent process-id of 989.Nm . 990.It Va .MAKE.SAVE_DOLLARS 991value should be a boolean that controls whether 992.Ql $$ 993are preserved when doing 994.Ql := 995assignments. 996The default is true, for compatibility with other makes. 997If set to false, 998.Ql $$ 999becomes 1000.Ql $ 1001per normal evaluation rules. 1002.It Va MAKE_PRINT_VAR_ON_ERROR 1003When 1004.Nm 1005stops due to an error, it sets 1006.Ql Va .ERROR_TARGET 1007to the name of the target that failed, 1008.Ql Va .ERROR_CMD 1009to the commands of the failed target, 1010and in "meta" mode, it also sets 1011.Ql Va .ERROR_CWD 1012to the 1013.Xr getcwd 3 , 1014and 1015.Ql Va .ERROR_META_FILE 1016to the path of the meta file (if any) describing the failed target. 1017It then prints its name and the value of 1018.Ql Va .CURDIR 1019as well as the value of any variables named in 1020.Ql Va MAKE_PRINT_VAR_ON_ERROR . 1021.It Va .newline 1022This variable is simply assigned a newline character as its value. 1023This allows expansions using the 1024.Cm \&:@ 1025modifier to put a newline between 1026iterations of the loop rather than a space. 1027For example, the printing of 1028.Ql Va MAKE_PRINT_VAR_ON_ERROR 1029could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}. 1030.It Va .OBJDIR 1031A path to the directory where the targets are built. 1032Its value is determined by trying to 1033.Xr chdir 2 1034to the following directories in order and using the first match: 1035.Bl -enum 1036.It 1037.Ev ${MAKEOBJDIRPREFIX}${.CURDIR} 1038.Pp 1039(Only if 1040.Ql Ev MAKEOBJDIRPREFIX 1041is set in the environment or on the command line.) 1042.It 1043.Ev ${MAKEOBJDIR} 1044.Pp 1045(Only if 1046.Ql Ev MAKEOBJDIR 1047is set in the environment or on the command line.) 1048.It 1049.Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE} 1050.It 1051.Ev ${.CURDIR} Ns Pa /obj 1052.It 1053.Pa /usr/obj/ Ns Ev ${.CURDIR} 1054.It 1055.Ev ${.CURDIR} 1056.El 1057.Pp 1058Variable expansion is performed on the value before it's used, 1059so expressions such as 1060.Dl ${.CURDIR:S,^/usr/src,/var/obj,} 1061may be used. 1062This is especially useful with 1063.Ql Ev MAKEOBJDIR . 1064.Pp 1065.Ql Va .OBJDIR 1066may be modified in the makefile via the special target 1067.Ql Ic .OBJDIR . 1068In all cases, 1069.Nm 1070will 1071.Xr chdir 2 1072to the specified directory if it exists, and set 1073.Ql Va .OBJDIR 1074and 1075.Ql Ev PWD 1076to that directory before executing any targets. 1077. 1078.It Va .PARSEDIR 1079A path to the directory of the current 1080.Ql Pa Makefile 1081being parsed. 1082.It Va .PARSEFILE 1083The basename of the current 1084.Ql Pa Makefile 1085being parsed. 1086This variable and 1087.Ql Va .PARSEDIR 1088are both set only while the 1089.Ql Pa Makefiles 1090are being parsed. 1091If you want to retain their current values, assign them to a variable 1092using assignment with expansion: 1093.Pq Ql Cm \&:= . 1094.It Va .PATH 1095A variable that represents the list of directories that 1096.Nm 1097will search for files. 1098The search list should be updated using the target 1099.Ql Va .PATH 1100rather than the variable. 1101.It Ev PWD 1102Alternate path to the current directory. 1103.Nm 1104normally sets 1105.Ql Va .CURDIR 1106to the canonical path given by 1107.Xr getcwd 3 . 1108However, if the environment variable 1109.Ql Ev PWD 1110is set and gives a path to the current directory, then 1111.Nm 1112sets 1113.Ql Va .CURDIR 1114to the value of 1115.Ql Ev PWD 1116instead. 1117This behavior is disabled if 1118.Ql Ev MAKEOBJDIRPREFIX 1119is set or 1120.Ql Ev MAKEOBJDIR 1121contains a variable transform. 1122.Ql Ev PWD 1123is set to the value of 1124.Ql Va .OBJDIR 1125for all programs which 1126.Nm 1127executes. 1128.It Ev .TARGETS 1129The list of targets explicitly specified on the command line, if any. 1130.It Ev VPATH 1131Colon-separated 1132.Pq Dq \&: 1133lists of directories that 1134.Nm 1135will search for files. 1136The variable is supported for compatibility with old make programs only, 1137use 1138.Ql Va .PATH 1139instead. 1140.El 1141.Ss Variable modifiers 1142Variable expansion may be modified to select or modify each word of the 1143variable (where a 1144.Dq word 1145is white-space delimited sequence of characters). 1146The general format of a variable expansion is as follows: 1147.Pp 1148.Dl ${variable[:modifier[:...]]} 1149.Pp 1150Each modifier begins with a colon, 1151which may be escaped with a backslash 1152.Pq Ql \e . 1153.Pp 1154A set of modifiers can be specified via a variable, as follows: 1155.Pp 1156.Dl modifier_variable=modifier[:...] 1157.Dl ${variable:${modifier_variable}[:...]} 1158.Pp 1159In this case the first modifier in the modifier_variable does not 1160start with a colon, since that must appear in the referencing 1161variable. 1162If any of the modifiers in the modifier_variable contain a dollar sign 1163.Pq Ql $ , 1164these must be doubled to avoid early expansion. 1165.Pp 1166The supported modifiers are: 1167.Bl -tag -width EEE 1168.It Cm \&:E 1169Replaces each word in the variable with its suffix. 1170.It Cm \&:H 1171Replaces each word in the variable with everything but the last component. 1172.It Cm \&:M Ns Ar pattern 1173Select only those words that match 1174.Ar pattern . 1175The standard shell wildcard characters 1176.Pf ( Ql * , 1177.Ql \&? , 1178and 1179.Ql Oo Oc ) 1180may 1181be used. 1182The wildcard characters may be escaped with a backslash 1183.Pq Ql \e . 1184As a consequence of the way values are split into words, matched, 1185and then joined, a construct like 1186.Dl ${VAR:M*} 1187will normalize the inter-word spacing, removing all leading and 1188trailing space, and converting multiple consecutive spaces 1189to single spaces. 1190. 1191.It Cm \&:N Ns Ar pattern 1192This is identical to 1193.Ql Cm \&:M , 1194but selects all words which do not match 1195.Ar pattern . 1196.It Cm \&:O 1197Order every word in variable alphabetically. 1198To sort words in 1199reverse order use the 1200.Ql Cm \&:O:[-1..1] 1201combination of modifiers. 1202.It Cm \&:Ox 1203Randomize words in variable. 1204The results will be different each time you are referring to the 1205modified variable; use the assignment with expansion 1206.Pq Ql Cm \&:= 1207to prevent such behavior. 1208For example, 1209.Bd -literal -offset indent 1210LIST= uno due tre quattro 1211RANDOM_LIST= ${LIST:Ox} 1212STATIC_RANDOM_LIST:= ${LIST:Ox} 1213 1214all: 1215 @echo "${RANDOM_LIST}" 1216 @echo "${RANDOM_LIST}" 1217 @echo "${STATIC_RANDOM_LIST}" 1218 @echo "${STATIC_RANDOM_LIST}" 1219.Ed 1220may produce output similar to: 1221.Bd -literal -offset indent 1222quattro due tre uno 1223tre due quattro uno 1224due uno quattro tre 1225due uno quattro tre 1226.Ed 1227.It Cm \&:Q 1228Quotes every shell meta-character in the variable, so that it can be passed 1229safely through recursive invocations of 1230.Nm . 1231.It Cm \&:R 1232Replaces each word in the variable with everything but its suffix. 1233.It Cm \&:range[=count] 1234The value is an integer sequence representing the words of the original 1235value, or the supplied 1236.Va count . 1237.It Cm \&:gmtime[=utc] 1238The value is a format string for 1239.Xr strftime 3 , 1240using 1241.Xr gmtime 3 . 1242If a 1243.Va utc 1244value is not provided or is 0, the current time is used. 1245.It Cm \&:hash 1246Compute a 32-bit hash of the value and encode it as hex digits. 1247.It Cm \&:localtime[=utc] 1248The value is a format string for 1249.Xr strftime 3 , 1250using 1251.Xr localtime 3 . 1252If a 1253.Va utc 1254value is not provided or is 0, the current time is used. 1255.It Cm \&:tA 1256Attempt to convert variable to an absolute path using 1257.Xr realpath 3 , 1258if that fails, the value is unchanged. 1259.It Cm \&:tl 1260Converts variable to lower-case letters. 1261.It Cm \&:ts Ns Ar c 1262Words in the variable are normally separated by a space on expansion. 1263This modifier sets the separator to the character 1264.Ar c . 1265If 1266.Ar c 1267is omitted, then no separator is used. 1268The common escapes (including octal numeric codes), work as expected. 1269.It Cm \&:tu 1270Converts variable to upper-case letters. 1271.It Cm \&:tW 1272Causes the value to be treated as a single word 1273(possibly containing embedded white space). 1274See also 1275.Ql Cm \&:[*] . 1276.It Cm \&:tw 1277Causes the value to be treated as a sequence of 1278words delimited by white space. 1279See also 1280.Ql Cm \&:[@] . 1281.Sm off 1282.It Cm \&:S No \&/ Ar old_string No \&/ Ar new_string No \&/ Op Cm 1gW 1283.Sm on 1284Modify the first occurrence of 1285.Ar old_string 1286in the variable's value, replacing it with 1287.Ar new_string . 1288If a 1289.Ql g 1290is appended to the last slash of the pattern, all occurrences 1291in each word are replaced. 1292If a 1293.Ql 1 1294is appended to the last slash of the pattern, only the first word 1295is affected. 1296If a 1297.Ql W 1298is appended to the last slash of the pattern, 1299then the value is treated as a single word 1300(possibly containing embedded white space). 1301If 1302.Ar old_string 1303begins with a caret 1304.Pq Ql ^ , 1305.Ar old_string 1306is anchored at the beginning of each word. 1307If 1308.Ar old_string 1309ends with a dollar sign 1310.Pq Ql \&$ , 1311it is anchored at the end of each word. 1312Inside 1313.Ar new_string , 1314an ampersand 1315.Pq Ql & 1316is replaced by 1317.Ar old_string 1318(without any 1319.Ql ^ 1320or 1321.Ql \&$ ) . 1322Any character may be used as a delimiter for the parts of the modifier 1323string. 1324The anchoring, ampersand and delimiter characters may be escaped with a 1325backslash 1326.Pq Ql \e . 1327.Pp 1328Variable expansion occurs in the normal fashion inside both 1329.Ar old_string 1330and 1331.Ar new_string 1332with the single exception that a backslash is used to prevent the expansion 1333of a dollar sign 1334.Pq Ql \&$ , 1335not a preceding dollar sign as is usual. 1336.Sm off 1337.It Cm \&:C No \&/ Ar pattern No \&/ Ar replacement No \&/ Op Cm 1gW 1338.Sm on 1339The 1340.Cm \&:C 1341modifier is just like the 1342.Cm \&:S 1343modifier except that the old and new strings, instead of being 1344simple strings, are an extended regular expression (see 1345.Xr regex 3 ) 1346string 1347.Ar pattern 1348and an 1349.Xr ed 1 Ns \-style 1350string 1351.Ar replacement . 1352Normally, the first occurrence of the pattern 1353.Ar pattern 1354in each word of the value is substituted with 1355.Ar replacement . 1356The 1357.Ql 1 1358modifier causes the substitution to apply to at most one word; the 1359.Ql g 1360modifier causes the substitution to apply to as many instances of the 1361search pattern 1362.Ar pattern 1363as occur in the word or words it is found in; the 1364.Ql W 1365modifier causes the value to be treated as a single word 1366(possibly containing embedded white space). 1367Note that 1368.Ql 1 1369and 1370.Ql g 1371are orthogonal; the former specifies whether multiple words are 1372potentially affected, the latter whether multiple substitutions can 1373potentially occur within each affected word. 1374.Pp 1375As for the 1376.Cm \&:S 1377modifier, the 1378.Ar pattern 1379and 1380.Ar replacement 1381are subjected to variable expansion before being parsed as 1382regular expressions. 1383.It Cm \&:T 1384Replaces each word in the variable with its last component. 1385.It Cm \&:u 1386Remove adjacent duplicate words (like 1387.Xr uniq 1 ) . 1388.Sm off 1389.It Cm \&:\&? Ar true_string Cm \&: Ar false_string 1390.Sm on 1391If the variable name (not its value), when parsed as a .if conditional 1392expression, evaluates to true, return as its value the 1393.Ar true_string , 1394otherwise return the 1395.Ar false_string . 1396Since the variable name is used as the expression, \&:\&? must be the 1397first modifier after the variable name itself - which will, of course, 1398usually contain variable expansions. 1399A common error is trying to use expressions like 1400.Dl ${NUMBERS:M42:?match:no} 1401which actually tests defined(NUMBERS), 1402to determine is any words match "42" you need to use something like: 1403.Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} . 1404.It Ar :old_string=new_string 1405This is the 1406.At V 1407style variable substitution. 1408It must be the last modifier specified. 1409If 1410.Ar old_string 1411or 1412.Ar new_string 1413do not contain the pattern matching character 1414.Ar % 1415then it is assumed that they are 1416anchored at the end of each word, so only suffixes or entire 1417words may be replaced. 1418Otherwise 1419.Ar % 1420is the substring of 1421.Ar old_string 1422to be replaced in 1423.Ar new_string . 1424.Pp 1425Variable expansion occurs in the normal fashion inside both 1426.Ar old_string 1427and 1428.Ar new_string 1429with the single exception that a backslash is used to prevent the 1430expansion of a dollar sign 1431.Pq Ql \&$ , 1432not a preceding dollar sign as is usual. 1433.Sm off 1434.It Cm \&:@ Ar temp Cm @ Ar string Cm @ 1435.Sm on 1436This is the loop expansion mechanism from the OSF Development 1437Environment (ODE) make. 1438Unlike 1439.Cm \&.for 1440loops expansion occurs at the time of 1441reference. 1442Assign 1443.Ar temp 1444to each word in the variable and evaluate 1445.Ar string . 1446The ODE convention is that 1447.Ar temp 1448should start and end with a period. 1449For example. 1450.Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@} 1451.Pp 1452However a single character variable is often more readable: 1453.Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@} 1454.It Cm \&:_[=var] 1455Save the current variable value in 1456.Ql $_ 1457or the named 1458.Va var 1459for later reference. 1460Example usage: 1461.Bd -literal -offset indent 1462M_cmpv.units = 1 1000 1000000 1463M_cmpv = S,., ,g:_:range:@i@+ $${_:[-$$i]} \&\\ 1464\\* $${M_cmpv.units:[$$i]}@:S,^,expr 0 ,1:sh 1465 1466.Dv .if ${VERSION:${M_cmpv}} < ${3.1.12:L:${M_cmpv}} 1467 1468.Ed 1469Here 1470.Ql $_ 1471is used to save the result of the 1472.Ql :S 1473modifier which is later referenced using the index values from 1474.Ql :range . 1475.It Cm \&:U Ns Ar newval 1476If the variable is undefined 1477.Ar newval 1478is the value. 1479If the variable is defined, the existing value is returned. 1480This is another ODE make feature. 1481It is handy for setting per-target CFLAGS for instance: 1482.Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}} 1483If a value is only required if the variable is undefined, use: 1484.Dl ${VAR:D:Unewval} 1485.It Cm \&:D Ns Ar newval 1486If the variable is defined 1487.Ar newval 1488is the value. 1489.It Cm \&:L 1490The name of the variable is the value. 1491.It Cm \&:P 1492The path of the node which has the same name as the variable 1493is the value. 1494If no such node exists or its path is null, then the 1495name of the variable is used. 1496In order for this modifier to work, the name (node) must at least have 1497appeared on the rhs of a dependency. 1498.Sm off 1499.It Cm \&:\&! Ar cmd Cm \&! 1500.Sm on 1501The output of running 1502.Ar cmd 1503is the value. 1504.It Cm \&:sh 1505If the variable is non-empty it is run as a command and the output 1506becomes the new value. 1507.It Cm \&::= Ns Ar str 1508The variable is assigned the value 1509.Ar str 1510after substitution. 1511This modifier and its variations are useful in 1512obscure situations such as wanting to set a variable when shell commands 1513are being parsed. 1514These assignment modifiers always expand to 1515nothing, so if appearing in a rule line by themselves should be 1516preceded with something to keep 1517.Nm 1518happy. 1519.Pp 1520The 1521.Ql Cm \&:: 1522helps avoid false matches with the 1523.At V 1524style 1525.Cm \&:= 1526modifier and since substitution always occurs the 1527.Cm \&::= 1528form is vaguely appropriate. 1529.It Cm \&::?= Ns Ar str 1530As for 1531.Cm \&::= 1532but only if the variable does not already have a value. 1533.It Cm \&::+= Ns Ar str 1534Append 1535.Ar str 1536to the variable. 1537.It Cm \&::!= Ns Ar cmd 1538Assign the output of 1539.Ar cmd 1540to the variable. 1541.It Cm \&:\&[ Ns Ar range Ns Cm \&] 1542Selects one or more words from the value, 1543or performs other operations related to the way in which the 1544value is divided into words. 1545.Pp 1546Ordinarily, a value is treated as a sequence of words 1547delimited by white space. 1548Some modifiers suppress this behavior, 1549causing a value to be treated as a single word 1550(possibly containing embedded white space). 1551An empty value, or a value that consists entirely of white-space, 1552is treated as a single word. 1553For the purposes of the 1554.Ql Cm \&:[] 1555modifier, the words are indexed both forwards using positive integers 1556(where index 1 represents the first word), 1557and backwards using negative integers 1558(where index \-1 represents the last word). 1559.Pp 1560The 1561.Ar range 1562is subjected to variable expansion, and the expanded result is 1563then interpreted as follows: 1564.Bl -tag -width index 1565.\" :[n] 1566.It Ar index 1567Selects a single word from the value. 1568.\" :[start..end] 1569.It Ar start Ns Cm \&.. Ns Ar end 1570Selects all words from 1571.Ar start 1572to 1573.Ar end , 1574inclusive. 1575For example, 1576.Ql Cm \&:[2..-1] 1577selects all words from the second word to the last word. 1578If 1579.Ar start 1580is greater than 1581.Ar end , 1582then the words are output in reverse order. 1583For example, 1584.Ql Cm \&:[-1..1] 1585selects all the words from last to first. 1586.\" :[*] 1587.It Cm \&* 1588Causes subsequent modifiers to treat the value as a single word 1589(possibly containing embedded white space). 1590Analogous to the effect of 1591\&"$*\&" 1592in Bourne shell. 1593.\" :[0] 1594.It 0 1595Means the same as 1596.Ql Cm \&:[*] . 1597.\" :[*] 1598.It Cm \&@ 1599Causes subsequent modifiers to treat the value as a sequence of words 1600delimited by white space. 1601Analogous to the effect of 1602\&"$@\&" 1603in Bourne shell. 1604.\" :[#] 1605.It Cm \&# 1606Returns the number of words in the value. 1607.El \" :[range] 1608.El 1609.Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS 1610Makefile inclusion, conditional structures and for loops reminiscent 1611of the C programming language are provided in 1612.Nm . 1613All such structures are identified by a line beginning with a single 1614dot 1615.Pq Ql \&. 1616character. 1617Files are included with either 1618.Cm \&.include Aq Ar file 1619or 1620.Cm \&.include Pf \*q Ar file Ns \*q . 1621Variables between the angle brackets or double quotes are expanded 1622to form the file name. 1623If angle brackets are used, the included makefile is expected to be in 1624the system makefile directory. 1625If double quotes are used, the including makefile's directory and any 1626directories specified using the 1627.Fl I 1628option are searched before the system 1629makefile directory. 1630For compatibility with other versions of 1631.Nm 1632.Ql include file ... 1633is also accepted. 1634.Pp 1635If the include statement is written as 1636.Cm .-include 1637or as 1638.Cm .sinclude 1639then errors locating and/or opening include files are ignored. 1640.Pp 1641If the include statement is written as 1642.Cm .dinclude 1643not only are errors locating and/or opening include files ignored, 1644but stale dependencies within the included file will be ignored 1645just like 1646.Va .MAKE.DEPENDFILE . 1647.Pp 1648Conditional expressions are also preceded by a single dot as the first 1649character of a line. 1650The possible conditionals are as follows: 1651.Bl -tag -width Ds 1652.It Ic .error Ar message 1653The message is printed along with the name of the makefile and line number, 1654then 1655.Nm 1656will exit. 1657.It Ic .export Ar variable ... 1658Export the specified global variable. 1659If no variable list is provided, all globals are exported 1660except for internal variables (those that start with 1661.Ql \&. ) . 1662This is not affected by the 1663.Fl X 1664flag, so should be used with caution. 1665For compatibility with other 1666.Nm 1667programs 1668.Ql export variable=value 1669is also accepted. 1670.Pp 1671Appending a variable name to 1672.Va .MAKE.EXPORTED 1673is equivalent to exporting a variable. 1674.It Ic .export-env Ar variable ... 1675The same as 1676.Ql .export , 1677except that the variable is not appended to 1678.Va .MAKE.EXPORTED . 1679This allows exporting a value to the environment which is different from that 1680used by 1681.Nm 1682internally. 1683.It Ic .export-literal Ar variable ... 1684The same as 1685.Ql .export-env , 1686except that variables in the value are not expanded. 1687.It Ic .info Ar message 1688The message is printed along with the name of the makefile and line number. 1689.It Ic .undef Ar variable 1690Un-define the specified global variable. 1691Only global variables may be un-defined. 1692.It Ic .unexport Ar variable ... 1693The opposite of 1694.Ql .export . 1695The specified global 1696.Va variable 1697will be removed from 1698.Va .MAKE.EXPORTED . 1699If no variable list is provided, all globals are unexported, 1700and 1701.Va .MAKE.EXPORTED 1702deleted. 1703.It Ic .unexport-env 1704Unexport all globals previously exported and 1705clear the environment inherited from the parent. 1706This operation will cause a memory leak of the original environment, 1707so should be used sparingly. 1708Testing for 1709.Va .MAKE.LEVEL 1710being 0, would make sense. 1711Also note that any variables which originated in the parent environment 1712should be explicitly preserved if desired. 1713For example: 1714.Bd -literal -offset indent 1715.Li .if ${.MAKE.LEVEL} == 0 1716PATH := ${PATH} 1717.Li .unexport-env 1718.Li .export PATH 1719.Li .endif 1720.Pp 1721.Ed 1722Would result in an environment containing only 1723.Ql Ev PATH , 1724which is the minimal useful environment. 1725Actually 1726.Ql Ev .MAKE.LEVEL 1727will also be pushed into the new environment. 1728.It Ic .warning Ar message 1729The message prefixed by 1730.Ql Pa warning: 1731is printed along with the name of the makefile and line number. 1732.It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ... 1733Test the value of an expression. 1734.It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1735Test the value of a variable. 1736.It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1737Test the value of a variable. 1738.It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1739Test the target being built. 1740.It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ... 1741Test the target being built. 1742.It Ic .else 1743Reverse the sense of the last conditional. 1744.It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ... 1745A combination of 1746.Ql Ic .else 1747followed by 1748.Ql Ic .if . 1749.It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1750A combination of 1751.Ql Ic .else 1752followed by 1753.Ql Ic .ifdef . 1754.It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ... 1755A combination of 1756.Ql Ic .else 1757followed by 1758.Ql Ic .ifndef . 1759.It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1760A combination of 1761.Ql Ic .else 1762followed by 1763.Ql Ic .ifmake . 1764.It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ... 1765A combination of 1766.Ql Ic .else 1767followed by 1768.Ql Ic .ifnmake . 1769.It Ic .endif 1770End the body of the conditional. 1771.El 1772.Pp 1773The 1774.Ar operator 1775may be any one of the following: 1776.Bl -tag -width "Cm XX" 1777.It Cm \&|\&| 1778Logical OR. 1779.It Cm \&&& 1780Logical 1781.Tn AND ; 1782of higher precedence than 1783.Dq \&|\&| . 1784.El 1785.Pp 1786As in C, 1787.Nm 1788will only evaluate a conditional as far as is necessary to determine 1789its value. 1790Parentheses may be used to change the order of evaluation. 1791The boolean operator 1792.Ql Ic \&! 1793may be used to logically negate an entire 1794conditional. 1795It is of higher precedence than 1796.Ql Ic \&&& . 1797.Pp 1798The value of 1799.Ar expression 1800may be any of the following: 1801.Bl -tag -width defined 1802.It Ic defined 1803Takes a variable name as an argument and evaluates to true if the variable 1804has been defined. 1805.It Ic make 1806Takes a target name as an argument and evaluates to true if the target 1807was specified as part of 1808.Nm Ns 's 1809command line or was declared the default target (either implicitly or 1810explicitly, see 1811.Va .MAIN ) 1812before the line containing the conditional. 1813.It Ic empty 1814Takes a variable, with possible modifiers, and evaluates to true if 1815the expansion of the variable would result in an empty string. 1816.It Ic exists 1817Takes a file name as an argument and evaluates to true if the file exists. 1818The file is searched for on the system search path (see 1819.Va .PATH ) . 1820.It Ic target 1821Takes a target name as an argument and evaluates to true if the target 1822has been defined. 1823.It Ic commands 1824Takes a target name as an argument and evaluates to true if the target 1825has been defined and has commands associated with it. 1826.El 1827.Pp 1828.Ar Expression 1829may also be an arithmetic or string comparison. 1830Variable expansion is 1831performed on both sides of the comparison, after which the integral 1832values are compared. 1833A value is interpreted as hexadecimal if it is 1834preceded by 0x, otherwise it is decimal; octal numbers are not supported. 1835The standard C relational operators are all supported. 1836If after 1837variable expansion, either the left or right hand side of a 1838.Ql Ic == 1839or 1840.Ql Ic "!=" 1841operator is not an integral value, then 1842string comparison is performed between the expanded 1843variables. 1844If no relational operator is given, it is assumed that the expanded 1845variable is being compared against 0 or an empty string in the case 1846of a string comparison. 1847.Pp 1848When 1849.Nm 1850is evaluating one of these conditional expressions, and it encounters 1851a (white-space separated) word it doesn't recognize, either the 1852.Dq make 1853or 1854.Dq defined 1855expression is applied to it, depending on the form of the conditional. 1856If the form is 1857.Ql Ic .ifdef , 1858.Ql Ic .ifndef , 1859or 1860.Ql Ic .if 1861the 1862.Dq defined 1863expression is applied. 1864Similarly, if the form is 1865.Ql Ic .ifmake 1866or 1867.Ql Ic .ifnmake , 1868the 1869.Dq make 1870expression is applied. 1871.Pp 1872If the conditional evaluates to true the parsing of the makefile continues 1873as before. 1874If it evaluates to false, the following lines are skipped. 1875In both cases this continues until a 1876.Ql Ic .else 1877or 1878.Ql Ic .endif 1879is found. 1880.Pp 1881For loops are typically used to apply a set of rules to a list of files. 1882The syntax of a for loop is: 1883.Pp 1884.Bl -tag -compact -width Ds 1885.It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression 1886.It Aq make-rules 1887.It Ic \&.endfor 1888.El 1889.Pp 1890After the for 1891.Ic expression 1892is evaluated, it is split into words. 1893On each iteration of the loop, one word is taken and assigned to each 1894.Ic variable , 1895in order, and these 1896.Ic variables 1897are substituted into the 1898.Ic make-rules 1899inside the body of the for loop. 1900The number of words must come out even; that is, if there are three 1901iteration variables, the number of words provided must be a multiple 1902of three. 1903.Sh COMMENTS 1904Comments begin with a hash 1905.Pq Ql \&# 1906character, anywhere but in a shell 1907command line, and continue to the end of an unescaped new line. 1908.Sh SPECIAL SOURCES (ATTRIBUTES) 1909.Bl -tag -width .IGNOREx 1910.It Ic .EXEC 1911Target is never out of date, but always execute commands anyway. 1912.It Ic .IGNORE 1913Ignore any errors from the commands associated with this target, exactly 1914as if they all were preceded by a dash 1915.Pq Ql \- . 1916.\" .It Ic .INVISIBLE 1917.\" XXX 1918.\" .It Ic .JOIN 1919.\" XXX 1920.It Ic .MADE 1921Mark all sources of this target as being up-to-date. 1922.It Ic .MAKE 1923Execute the commands associated with this target even if the 1924.Fl n 1925or 1926.Fl t 1927options were specified. 1928Normally used to mark recursive 1929.Nm Ns s . 1930.It Ic .META 1931Create a meta file for the target, even if it is flagged as 1932.Ic .PHONY , 1933.Ic .MAKE , 1934or 1935.Ic .SPECIAL . 1936Usage in conjunction with 1937.Ic .MAKE 1938is the most likely case. 1939In "meta" mode, the target is out-of-date if the meta file is missing. 1940.It Ic .NOMETA 1941Do not create a meta file for the target. 1942Meta files are also not created for 1943.Ic .PHONY , 1944.Ic .MAKE , 1945or 1946.Ic .SPECIAL 1947targets. 1948.It Ic .NOMETA_CMP 1949Ignore differences in commands when deciding if target is out of date. 1950This is useful if the command contains a value which always changes. 1951If the number of commands change, though, the target will still be out of date. 1952The same effect applies to any command line that uses the variable 1953.Va .OODATE , 1954which can be used for that purpose even when not otherwise needed or desired: 1955.Bd -literal -offset indent 1956 1957skip-compare-for-some: 1958 @echo this will be compared 1959 @echo this will not ${.OODATE:M.NOMETA_CMP} 1960 @echo this will also be compared 1961 1962.Ed 1963The 1964.Cm \&:M 1965pattern suppresses any expansion of the unwanted variable. 1966.It Ic .NOPATH 1967Do not search for the target in the directories specified by 1968.Ic .PATH . 1969.It Ic .NOTMAIN 1970Normally 1971.Nm 1972selects the first target it encounters as the default target to be built 1973if no target was specified. 1974This source prevents this target from being selected. 1975.It Ic .OPTIONAL 1976If a target is marked with this attribute and 1977.Nm 1978can't figure out how to create it, it will ignore this fact and assume 1979the file isn't needed or already exists. 1980.It Ic .PHONY 1981The target does not 1982correspond to an actual file; it is always considered to be out of date, 1983and will not be created with the 1984.Fl t 1985option. 1986Suffix-transformation rules are not applied to 1987.Ic .PHONY 1988targets. 1989.It Ic .PRECIOUS 1990When 1991.Nm 1992is interrupted, it normally removes any partially made targets. 1993This source prevents the target from being removed. 1994.It Ic .RECURSIVE 1995Synonym for 1996.Ic .MAKE . 1997.It Ic .SILENT 1998Do not echo any of the commands associated with this target, exactly 1999as if they all were preceded by an at sign 2000.Pq Ql @ . 2001.It Ic .USE 2002Turn the target into 2003.Nm Ns 's 2004version of a macro. 2005When the target is used as a source for another target, the other target 2006acquires the commands, sources, and attributes (except for 2007.Ic .USE ) 2008of the 2009source. 2010If the target already has commands, the 2011.Ic .USE 2012target's commands are appended 2013to them. 2014.It Ic .USEBEFORE 2015Exactly like 2016.Ic .USE , 2017but prepend the 2018.Ic .USEBEFORE 2019target commands to the target. 2020.It Ic .WAIT 2021If 2022.Ic .WAIT 2023appears in a dependency line, the sources that precede it are 2024made before the sources that succeed it in the line. 2025Since the dependents of files are not made until the file itself 2026could be made, this also stops the dependents being built unless they 2027are needed for another branch of the dependency tree. 2028So given: 2029.Bd -literal 2030x: a .WAIT b 2031 echo x 2032a: 2033 echo a 2034b: b1 2035 echo b 2036b1: 2037 echo b1 2038 2039.Ed 2040the output is always 2041.Ql a , 2042.Ql b1 , 2043.Ql b , 2044.Ql x . 2045.br 2046The ordering imposed by 2047.Ic .WAIT 2048is only relevant for parallel makes. 2049.El 2050.Sh SPECIAL TARGETS 2051Special targets may not be included with other targets, i.e. they must be 2052the only target specified. 2053.Bl -tag -width .BEGINx 2054.It Ic .BEGIN 2055Any command lines attached to this target are executed before anything 2056else is done. 2057.It Ic .DEFAULT 2058This is sort of a 2059.Ic .USE 2060rule for any target (that was used only as a 2061source) that 2062.Nm 2063can't figure out any other way to create. 2064Only the shell script is used. 2065The 2066.Ic .IMPSRC 2067variable of a target that inherits 2068.Ic .DEFAULT Ns 's 2069commands is set 2070to the target's own name. 2071.It Ic .DELETE_ON_ERROR 2072If this target is present in the makefile, it globally causes make to 2073delete targets whose commands fail. 2074(By default, only targets whose commands are interrupted during 2075execution are deleted. 2076This is the historical behavior.) 2077This setting can be used to help prevent half-finished or malformed 2078targets from being left around and corrupting future rebuilds. 2079.It Ic .END 2080Any command lines attached to this target are executed after everything 2081else is done. 2082.It Ic .ERROR 2083Any command lines attached to this target are executed when another target fails. 2084The 2085.Ic .ERROR_TARGET 2086variable is set to the target that failed. 2087See also 2088.Ic MAKE_PRINT_VAR_ON_ERROR . 2089.It Ic .IGNORE 2090Mark each of the sources with the 2091.Ic .IGNORE 2092attribute. 2093If no sources are specified, this is the equivalent of specifying the 2094.Fl i 2095option. 2096.It Ic .INTERRUPT 2097If 2098.Nm 2099is interrupted, the commands for this target will be executed. 2100.It Ic .MAIN 2101If no target is specified when 2102.Nm 2103is invoked, this target will be built. 2104.It Ic .MAKEFLAGS 2105This target provides a way to specify flags for 2106.Nm 2107when the makefile is used. 2108The flags are as if typed to the shell, though the 2109.Fl f 2110option will have 2111no effect. 2112.\" XXX: NOT YET!!!! 2113.\" .It Ic .NOTPARALLEL 2114.\" The named targets are executed in non parallel mode. 2115.\" If no targets are 2116.\" specified, then all targets are executed in non parallel mode. 2117.It Ic .NOPATH 2118Apply the 2119.Ic .NOPATH 2120attribute to any specified sources. 2121.It Ic .NOTPARALLEL 2122Disable parallel mode. 2123.It Ic .NO_PARALLEL 2124Synonym for 2125.Ic .NOTPARALLEL , 2126for compatibility with other pmake variants. 2127.It Ic .OBJDIR 2128The source is a new value for 2129.Ql Va .OBJDIR . 2130If it exists, 2131.Nm 2132will 2133.Xr chdir 2 2134to it and update the value of 2135.Ql Va .OBJDIR . 2136.It Ic .ORDER 2137The named targets are made in sequence. 2138This ordering does not add targets to the list of targets to be made. 2139Since the dependents of a target do not get built until the target itself 2140could be built, unless 2141.Ql a 2142is built by another part of the dependency graph, 2143the following is a dependency loop: 2144.Bd -literal 2145\&.ORDER: b a 2146b: a 2147.Ed 2148.Pp 2149The ordering imposed by 2150.Ic .ORDER 2151is only relevant for parallel makes. 2152.\" XXX: NOT YET!!!! 2153.\" .It Ic .PARALLEL 2154.\" The named targets are executed in parallel mode. 2155.\" If no targets are 2156.\" specified, then all targets are executed in parallel mode. 2157.It Ic .PATH 2158The sources are directories which are to be searched for files not 2159found in the current directory. 2160If no sources are specified, any previously specified directories are 2161deleted. 2162If the source is the special 2163.Ic .DOTLAST 2164target, then the current working 2165directory is searched last. 2166.It Ic .PATH. Ns Va suffix 2167Like 2168.Ic .PATH 2169but applies only to files with a particular suffix. 2170The suffix must have been previously declared with 2171.Ic .SUFFIXES . 2172.It Ic .PHONY 2173Apply the 2174.Ic .PHONY 2175attribute to any specified sources. 2176.It Ic .PRECIOUS 2177Apply the 2178.Ic .PRECIOUS 2179attribute to any specified sources. 2180If no sources are specified, the 2181.Ic .PRECIOUS 2182attribute is applied to every 2183target in the file. 2184.It Ic .SHELL 2185Sets the shell that 2186.Nm 2187will use to execute commands. 2188The sources are a set of 2189.Ar field=value 2190pairs. 2191.Bl -tag -width hasErrCtls 2192.It Ar name 2193This is the minimal specification, used to select one of the built-in 2194shell specs; 2195.Ar sh , 2196.Ar ksh , 2197and 2198.Ar csh . 2199.It Ar path 2200Specifies the path to the shell. 2201.It Ar hasErrCtl 2202Indicates whether the shell supports exit on error. 2203.It Ar check 2204The command to turn on error checking. 2205.It Ar ignore 2206The command to disable error checking. 2207.It Ar echo 2208The command to turn on echoing of commands executed. 2209.It Ar quiet 2210The command to turn off echoing of commands executed. 2211.It Ar filter 2212The output to filter after issuing the 2213.Ar quiet 2214command. 2215It is typically identical to 2216.Ar quiet . 2217.It Ar errFlag 2218The flag to pass the shell to enable error checking. 2219.It Ar echoFlag 2220The flag to pass the shell to enable command echoing. 2221.It Ar newline 2222The string literal to pass the shell that results in a single newline 2223character when used outside of any quoting characters. 2224.El 2225Example: 2226.Bd -literal 2227\&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e 2228 check="set \-e" ignore="set +e" \e 2229 echo="set \-v" quiet="set +v" filter="set +v" \e 2230 echoFlag=v errFlag=e newline="'\en'" 2231.Ed 2232.It Ic .SILENT 2233Apply the 2234.Ic .SILENT 2235attribute to any specified sources. 2236If no sources are specified, the 2237.Ic .SILENT 2238attribute is applied to every 2239command in the file. 2240.It Ic .STALE 2241This target gets run when a dependency file contains stale entries, having 2242.Va .ALLSRC 2243set to the name of that dependency file. 2244.It Ic .SUFFIXES 2245Each source specifies a suffix to 2246.Nm . 2247If no sources are specified, any previously specified suffixes are deleted. 2248It allows the creation of suffix-transformation rules. 2249.Pp 2250Example: 2251.Bd -literal 2252\&.SUFFIXES: .o 2253\&.c.o: 2254 cc \-o ${.TARGET} \-c ${.IMPSRC} 2255.Ed 2256.El 2257.Sh ENVIRONMENT 2258.Nm 2259uses the following environment variables, if they exist: 2260.Ev MACHINE , 2261.Ev MACHINE_ARCH , 2262.Ev MAKE , 2263.Ev MAKEFLAGS , 2264.Ev MAKEOBJDIR , 2265.Ev MAKEOBJDIRPREFIX , 2266.Ev MAKESYSPATH , 2267.Ev PWD , 2268and 2269.Ev TMPDIR . 2270.Pp 2271.Ev MAKEOBJDIRPREFIX 2272and 2273.Ev MAKEOBJDIR 2274may only be set in the environment or on the command line to 2275.Nm 2276and not as makefile variables; 2277see the description of 2278.Ql Va .OBJDIR 2279for more details. 2280.Sh FILES 2281.Bl -tag -width /usr/share/mk -compact 2282.It .depend 2283list of dependencies 2284.It Makefile 2285list of dependencies 2286.It makefile 2287list of dependencies 2288.It sys.mk 2289system makefile 2290.It /usr/share/mk 2291system makefile directory 2292.El 2293.Sh COMPATIBILITY 2294The basic make syntax is compatible between different versions of make; 2295however the special variables, variable modifiers and conditionals are not. 2296.Ss Older versions 2297An incomplete list of changes in older versions of 2298.Nm : 2299.Pp 2300The way that .for loop variables are substituted changed after 2301.Nx 5.0 2302so that they still appear to be variable expansions. 2303In particular this stops them being treated as syntax, and removes some 2304obscure problems using them in .if statements. 2305.Pp 2306The way that parallel makes are scheduled changed in 2307.Nx 4.0 2308so that .ORDER and .WAIT apply recursively to the dependent nodes. 2309The algorithms used may change again in the future. 2310.Ss Other make dialects 2311Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not 2312support most of the features of 2313.Nm 2314as described in this manual. 2315Most notably: 2316.Bl -bullet -offset indent 2317.It 2318The 2319.Ic .WAIT 2320and 2321.Ic .ORDER 2322declarations and most functionality pertaining to parallelization. 2323(GNU make supports parallelization but lacks these features needed to 2324control it effectively.) 2325.It 2326Directives, including for loops and conditionals and most of the 2327forms of include files. 2328(GNU make has its own incompatible and less powerful syntax for 2329conditionals.) 2330.It 2331All built-in variables that begin with a dot. 2332.It 2333Most of the special sources and targets that begin with a dot, 2334with the notable exception of 2335.Ic .PHONY , 2336.Ic .PRECIOUS , 2337and 2338.Ic .SUFFIXES . 2339.It 2340Variable modifiers, except for the 2341.Dl :old=new 2342string substitution, which does not portably support globbing with 2343.Ql % 2344and historically only works on declared suffixes. 2345.It 2346The 2347.Ic $> 2348variable even in its short form; most makes support this functionality 2349but its name varies. 2350.El 2351.Pp 2352Some features are somewhat more portable, such as assignment with 2353.Ic += , 2354.Ic ?= , 2355and 2356.Ic != . 2357The 2358.Ic .PATH 2359functionality is based on an older feature 2360.Ic VPATH 2361found in GNU make and many versions of SVR4 make; however, 2362historically its behavior is too ill-defined (and too buggy) to rely 2363upon. 2364.Pp 2365The 2366.Ic $@ 2367and 2368.Ic $< 2369variables are more or less universally portable, as is the 2370.Ic $(MAKE) 2371variable. 2372Basic use of suffix rules (for files only in the current directory, 2373not trying to chain transformations together, etc.) is also reasonably 2374portable. 2375.Sh SEE ALSO 2376.Xr mkdep 1 2377.Sh HISTORY 2378A 2379.Nm 2380command appeared in 2381.At v7 . 2382This 2383.Nm 2384implementation is based on Adam De Boor's pmake program which was written 2385for Sprite at Berkeley. 2386It was designed to be a parallel distributed make running jobs on different 2387machines using a daemon called 2388.Dq customs . 2389.Pp 2390Historically the target/dependency 2391.Dq FRC 2392has been used to FoRCe rebuilding (since the target/dependency 2393does not exist... unless someone creates an 2394.Dq FRC 2395file). 2396.Sh BUGS 2397The 2398.Nm 2399syntax is difficult to parse without actually acting of the data. 2400For instance finding the end of a variable use should involve scanning each 2401the modifiers using the correct terminator for each field. 2402In many places 2403.Nm 2404just counts {} and () in order to find the end of a variable expansion. 2405.Pp 2406There is no way of escaping a space character in a filename. 2407