Make archive errors non-fatal, causing make to just skip the remainder or all of the archive and continue after printing a message.
-B
Try to be backwards compatible by executing a single shell per command and by executing the commands to make the sources of a dependency line in sequence. This is turned on by default unless -j is used.
-C directory
Change to directory before reading the makefiles or doing anything else. If multiple -C options are specified, each is interpreted relative to the previous one: -C /-C etc is equivalent to -C /etc.
-D variable
Define variable to be 1, in the global context.
-d flags
Turn on debugging, and specify which portions of make are to print debugging information. Argument flags is one or more of the following:
A
Print all possible debugging information; equivalent to specifying all of the debugging flags.
a
Print debugging information about archive searching and caching.
c
Print debugging information about conditional evaluation.
d
Print debugging information about directory searching and caching.
f
Print debugging information about the execution of for loops.
"g1"
Print the input graph before making anything.
"g2"
Print the input graph after making everything, or before exiting on error.
j
Print debugging information about running multiple shells.
l
Print commands in Makefiles regardless of whether or not they are prefixed by @ or other "quiet" flags. Also known as "loud" behavior.
m
Print debugging information about making targets, including modification dates.
s
Print debugging information about suffix-transformation rules.
t
Print debugging information about target list maintenance.
v
Print debugging information about variable assignment.
-E variable
Specify a variable whose environment value (if any) will override macro assignments within makefiles.
-e
Specify that environment values override macro assignments within makefiles for all variables.
-f makefile
Specify a makefile to read instead of the default makefile and Makefile. If makefile is '', standard input is read. Multiple makefiles may be specified, and are read in the order specified.
-I directory
Specify a directory in which to search for makefiles and included makefiles. The system makefile directory (or directories, see the -m option) is automatically included as part of this list.
-i
Ignore non-zero exit of shell commands in the makefile. Equivalent to specifying '-' before each command line in the makefile.
-j max_jobs
Specify the maximum number of jobs that make may have running at any one time. Turns compatibility mode off, unless the B flag is also specified.
-k
Continue processing after errors are encountered, but only on those targets that do not depend on the target whose creation caused the error.
-m directory
Specify a directory in which to search for sys.mk and makefiles included via the <...> style. Multiple directories can be added to form a search path. This path will override the default system include path: /usr/share/mk. Furthermore, the system include path will be appended to the search path used for "..."-style inclusions (see the -I option).
-n
Display the commands that would have been executed, but do not actually execute them.
-P
Collate the output of a given job and display it only when the job finishes, instead of mixing the output of parallel jobs together. This option has no effect unless -j is used too.
-q
Do not execute any commands, but exit 0 if the specified targets are up-to-date and 1, otherwise.
-r
Do not use the built-in rules specified in the system makefile.
-S
Stop processing when an error is encountered. Default behaviour. This is needed to negate the -k option during recursive builds.
-s
Do not echo any commands as they are executed. Equivalent to specifying '@' before each command line in the makefile.
-t
Rather than re-building a target as specified in the makefile, create it or update its modification time to make it appear up-to-date.
-V variable
Print ’s idea of the value of variable, in the global context. Do not build any targets. Multiple instances of this option may be specified; the variables will be printed one per line, with a blank line for each null or undefined variable.
-v
Be extra verbose. For multi-job makes, this will cause file banners to be generated.
-X
When using the -V option to print the values of variables, do not recursively expand the values.
variable = value
Set the value of the variable variable to value.
-x warning_options
Specify extended warning options. This option may be specified several times. A warning_option can be prefixed with "no" in which case the warning is switched off. The currently available options are:
dirsyntax
Warn if anything except blanks and comments follows an .endif or .else directive.
See also the .WARN special target.
There are seven different types of lines in a makefile: file dependency specifications, shell commands, variable assignments, include statements, conditional directives, for loops, and comments.
In general, lines may be continued from one line to the next by ending them with a backslash (‘\’). The trailing newline character and initial whitespace on the following line are compressed into a single space.
A target is considered out-of-date if its modification time is less than those of any of its sources. Sources for a target accumulate over dependency lines when this operator is used. The target is removed if make is interrupted.
!
Targets are always re-created, but not until all sources have been examined and re-created as necessary. Sources for a target accumulate over dependency lines when this operator is used. The target is removed if make is interrupted.
::
If no sources are specified, the target is always re-created. Otherwise, a target is considered out-of-date if any of its sources has been modified more recently than the target. Sources for a target do not accumulate over dependency lines when this operator is used. The target will not be removed if make is interrupted.
Targets and sources may contain the shell wildcard expressions ‘?’, ‘*’, ‘[]’ and ‘{}’. The expressions ‘?’, ‘*’ and ‘[]’ may only be used as part of the final component of the target or source, and must be used to describe existing files. The expression ‘{}’ need not necessarily be used to describe existing files. Expansion is in directory order, not alphabetically as done in the shell.
Assign the value to the variable. Any previous value is overridden.
+=
Append the value to the current value of the variable.
?=
Assign the value to the variable if it is not already defined.
:=
Assign with expansion, i.e., expand the value before assigning it to the variable. Normally, expansion is not done until the variable is referenced.
!=
Expand the value and pass it to the shell for execution and assign the result to the variable. Any newlines in the result are replaced with spaces.
Any whitespace before the assigned value is removed; if the value is being appended, a single space is inserted between the previous contents of the variable and the appended value.
Variables are expanded by surrounding the variable name with either curly braces (‘{}’) or parentheses (‘()’) and preceding it with a dollar sign (‘$’). If the variable name contains only a single letter, the surrounding braces or parentheses are not required. This shorter form is not recommended.
Variable substitution occurs at two distinct times, depending on where the variable is being used. Variables in dependency lines are expanded as the line is read. Variables in shell commands are expanded when the shell command is executed.
The four different classes of variables (in order of increasing precedence) are:
Environment variables
Variables defined as part of ’s environment.
Global variables
Variables defined in the makefile or in included makefiles.
Command line variables
Variables defined as part of the command line and variables obtained from the MAKEFLAGS environment variable or the .MAKEFLAGS target.
Local variables
Variables that are defined specific to a certain target. The seven local variables are as follows:
.ALLSRC
The list of all sources for this target; also known as '>'.
.ARCHIVE
The name of the archive file; also known as '!'.
.IMPSRC
The name/path of the source from which the target is to be transformed (the "implied" source); also known as '<'.
.MEMBER
The name of the archive member; also known as '%'.
.OODATE
The list of sources for this target that were deemed out-of-date; also known as '?'.
.PREFIX
The file prefix of the file, containing only the file portion, no suffix or preceding directory components; also known as '*'.
.TARGET
The name of the target; also known as '@'.
The shorter forms '@', '!', '<', '%', '?', '>', and '*' are permitted for backward compatibility and are not recommended. The six variables '@F', '@D', '<F', '<D', '*F', and '*D' are permitted for compatibility with AT&T V makefiles and are not recommended.
Four of the local variables may be used in sources on dependency lines because they expand to the proper value for each target on the line. These variables are .TARGET, .PREFIX, .ARCHIVE, and .MEMBER.
In addition, make sets or knows about the following internal variables or environment variables:
$
A single dollar sign ‘$’, i.e. ‘$$’ expands to a single dollar sign.
MAKE
The name that make was executed with (argv [0]).
.CURDIR
A path to the directory where make was executed. The make utility sets .CURDIR to the canonical path given by getcwd(3).
.OBJDIR
A path to the directory where the targets are built. At startup, make searches for an alternate directory to place target files. It will attempt to change into this special directory and will search this directory for makefiles not found in the current directory. The following directories are tried in order:
${MAKEOBJDIRPREFIX}/‘pwd‘
${MAKEOBJDIR}
obj.${MACHINE}
obj
/usr/obj/‘pwd‘
The first directory that make successfully changes into is used. If either MAKEOBJDIRPREFIX or MAKEOBJDIR is set in the environment but make is unable to change into the corresponding directory, then the current directory is used without checking the remainder of the list. If they are undefined and make is unable to change into any of the remaining three directories, then the current directory is used. Note, that MAKEOBJDIRPREFIX and MAKEOBJDIR must be environment variables and should not be set on ’s command line.
The make utility sets .OBJDIR to the canonical path given by getcwd(3).
.MAKEFILE_LIST
As make reads various makefiles, including the default files and any obtained from the command line and .include directives, their names will be automatically appended to the .MAKEFILE_LIST variable. They are added right before make begins to parse them, so that the name of the current makefile is the last word in this variable.
.MAKEFLAGS
The environment variable MAKEFLAGS may contain anything that may be specified on ’s command line. Its contents are stored in ’s .MAKEFLAGS variable. All options and variable assignments specified on ’s command line are appended to the .MAKEFLAGS variable which is then entered into the environment as MAKEFLAGS for all programs which make executes. By modifying the contents of the .MAKEFLAGS variable, makefile can alter the contents of the MAKEFLAGS environment variable made available for all programs which make executes; compare with the .MAKEFLAGS special target below.
When passing macro definitions and flag arguments in the MAKEFLAGS environment variable, space and tab characters are quoted by preceding them with a backslash. When reading the MAKEFLAGS variable from the environment, all sequences of a backslash and one of space or tab are replaced just with their second character without causing a word break. Any other occurrences of a backslash are retained. Groups of unquoted space, tab and newline characters cause word breaking.
MFLAGS
This variable is provided for backward compatibility and contains all the options from the MAKEFLAGS environment variable plus any options specified on ’s command line.
.TARGETS
List of targets make is currently building.
.INCLUDES
See .INCLUDES special target.
.LIBS
See .LIBS special target.
MACHINE
Name of the machine architecture make is running on, obtained from the MACHINE environment variable, or through uname(3) if not defined.
MACHINE_ARCH
Name of the machine architecture make was compiled for, defined at compilation time.
VPATH
Makefiles may assign a colon-delimited list of directories to VPATH. These directories will be searched for source files by make after it has finished parsing all input makefiles.
Variable expansion may be modified to select or modify each word of the variable (where a "word" is whitespace-delimited sequence of characters). The general format of a variable expansion is as follows:
{variable[:modifier[:...]]}
Each modifier begins with a colon and one of the following special characters. The colon may be escaped with a backslash (‘\’). .Sm off
C / pattern Xo
/ replacement / [1g]
.Sm on Modify each word of the value, substituting every match of the extended regular expression pattern (see re_format(7)) with the ed 1 -style replacement string. Normally, the first occurrence of the pattern in each word of the value is changed. The ‘1’ modifier causes the substitution to apply to at most one word; the ‘g’ modifier causes the substitution to apply to as many instances of the search pattern as occur in the word or words it is found in. Note that ‘1’ and ‘g’ are orthogonal; the former specifies whether multiple words are potentially affected, the latter whether multiple substitutions can potentially occur within each affected word.
E
Replaces each word in the variable with its suffix.
H
Replaces each word in the variable with everything but the last component.
L
Converts variable to lower-case letters.
M pattern
Select only those words that match the rest of the modifier. The standard shell wildcard characters (‘*’, ‘?’, and ‘[]’) may be used. The wildcard characters may be escaped with a backslash (‘\’).
N pattern
This is identical to M, but selects all words which do not match the rest of the modifier.
O
Order every word in the variable alphabetically.
Q
Quotes every shell meta-character in the variable, so that it can be passed safely through recursive invocations of make.
R
Replaces each word in the variable with everything but its suffix. .Sm off
S / old_string Xo
/ new_string / [g]
.Sm on Modify the first occurrence of old_string in each word of the variable’s value, replacing it with new_string. If a ‘g’ is appended to the last slash of the pattern, all occurrences in each word are replaced. If old_string begins with a caret (‘^’), old_string is anchored at the beginning of each word. If old_string ends with a dollar sign (‘$’), it is anchored at the end of each word. Inside new_string, an ampersand (‘&’) is replaced by old_string. Any character may be used as a delimiter for the parts of the modifier string. The anchoring, ampersand, and delimiter characters may be escaped with a backslash (‘\’).
Variable expansion occurs in the normal fashion inside both old_string and new_string with the single exception that a backslash is used to prevent the expansion of a dollar sign (‘$’), not a preceding dollar sign as is usual.
old_string=new_string
This is the AT&T V style variable substitution. It must be the last modifier specified. If old_string or new_string do not contain the pattern matching character % then it is assumed that they are anchored at the end of each word, so only suffixes or entire words may be replaced. Otherwise % is the substring of old_string to be replaced in new_string
T
Replaces each word in the variable with its last component.
Include the specified makefile. Variables between the angle brackets or double quotes are expanded to form the file name. If angle brackets are used, the included makefile is expected to be in the system makefile directory. If double quotes are used, the including makefile’s directory and any directories specified using the -I option are searched before the system makefile directory.
.undef variable
Un-define the specified global variable. Only global variables may be un-defined.
.error message
Terminate processing of the makefile immediately. The filename of the makefile, the line on which the error was encountered and the specified message are printed to the standard error output and make terminates with exit code 1. Variables in the message are expanded.
.warning message
Emit a warning message. The filename of the makefile, the line on which the warning was encountered, and the specified message are printed to the standard error output. Variables in the message are expanded.
Conditionals are used to determine which parts of the Makefile to process. They are used similarly to the conditionals supported by the C pre-processor. The following conditionals are supported:
.if [!expression] [operator expression ...]
Test the value of an expression.
.ifdef [!variable] [operator variable ...]
Test the value of a variable.
.ifndef [!variable] [operator variable ...]
Test the value of a variable.
.ifmake [!target] [operator target ...]
Test the target being built.
.ifnmake [!target] [operator target ...]
Test the target being built.
.else
Reverse the sense of the last conditional.
.elif [!expression] [operator expression ...]
A combination of .else followed by .if.
.elifdef [!variable] [operator variable ...]
A combination of .else followed by .ifdef.
.elifndef [!variable] [operator variable ...]
A combination of .else followed by .ifndef.
.elifmake [!target] [operator target ...]
A combination of .else followed by .ifmake.
.elifnmake [!target] [operator target ...]
A combination of .else followed by .ifnmake.
.endif
End the body of the conditional.
The operator may be any one of the following:
||
logical OR
&&
Logical AND; of higher precedence than '||'.
As in C, make will only evaluate a conditional as far as is necessary to determine its value. Parentheses may be used to change the order of evaluation. The boolean operator '!' may be used to logically negate an entire conditional. It is of higher precedence than '&&'.
The value of expression may be any of the following:
defined
Takes a variable name as an argument and evaluates to true if the variable has been defined.
make
Takes a target name as an argument and evaluates to true if the target was specified as part of ’s command line or was declared the default target (either implicitly or explicitly, see .MAIN) before the line containing the conditional.
empty
Takes a variable, with possible modifiers, and evaluates to true if the expansion of the variable would result in an empty string.
exists
Takes a file name as an argument and evaluates to true if the file exists. The file is searched for on the system search path (see .PATH).
target
Takes a target name as an argument and evaluates to true if the target has been defined.
An expression may also be an arithmetic or string comparison, with the left-hand side being a variable expansion. Variable expansion is performed on both sides of the comparison, after which the integral values are compared. A value is interpreted as hexadecimal if it is preceded by 0x, otherwise it is decimal; octal numbers are not supported. The standard C relational operators are all supported. If after variable expansion, either the left or right hand side of a '==' or '!=' operator is not an integral value, then string comparison is performed between the expanded variables. If no relational operator is given, it is assumed that the expanded variable is being compared against 0.
When make is evaluating one of these conditional expressions, and it encounters a word it does not recognize, either the "make" or "defined" expression is applied to it, depending on the form of the conditional. If the form is .if, .ifdef or .ifndef, the "defined" expression is applied. Similarly, if the form is .ifmake or .ifnmake, the "make" expression is applied.
If the conditional evaluates to true the parsing of the makefile continues as before. If it evaluates to false, the following lines are skipped. In both cases this continues until a .else or .endif is found.
For loops are typically used to apply a set of rules to a list of files. The syntax of a for loop is:
.for variable in expression <make-rules> .endfor
After the for expression is evaluated, it is split into words. The iteration variable is successively set to each word, and substituted in the make-rules inside the body of the for loop.
Ignore any errors from the commands associated with this target, exactly as if they all were preceded by a dash (‘-’).
.MAKE
Execute the commands associated with this target even if the -n or -t options were specified. Normally used to mark recursive ’s.
.NOTMAIN
Normally make selects the first target it encounters as the default target to be built if no target was specified. This source prevents this target from being selected.
.OPTIONAL
If a target is marked with this attribute and make cannot figure out how to create it, it will ignore this fact and assume the file is not needed or already exists.
.PRECIOUS
When make is interrupted, it removes any partially made targets. This source prevents the target from being removed.
.SILENT
Do not echo any of the commands associated with this target, exactly as if they all were preceded by an at sign (‘@’).
.USE
Turn the target into ’s version of a macro. When the target is used as a source for another target, the other target acquires the commands, sources, and attributes (except for .USE) of the source. If the target already has commands, the .USE target’s commands are appended to them.
.WAIT
If special .WAIT source is appears in a dependency line, the sources that precede it are made before the sources that succeed it in the line. Loops are not being detected and targets that form loops will be silently ignored.
Any command lines attached to this target are executed before anything else is done.
.DEFAULT
This is sort of a .USE rule for any target (that was used only as a source) that make cannot figure out any other way to create. Only the shell script is used. The .IMPSRC variable of a target that inherits .DEFAULT ’s commands is set to the target’s own name.
.END
Any command lines attached to this target are executed after everything else is done.
.IGNORE
Mark each of the sources with the .IGNORE attribute. If no sources are specified, this is the equivalent of specifying the -i option.
.INCLUDES
A list of suffixes that indicate files that can be included in a source file. The suffix must have already been declared with .SUFFIXES; any suffix so declared will have the directories on its search path (see .PATH) placed in the .INCLUDES special variable, each preceded by a -I flag.
.INTERRUPT
If make is interrupted, the commands for this target will be executed.
.LIBS
This does for libraries what .INCLUDES does for include files, except that the flag used is -L .
.MAIN
If no target is specified when make is invoked, this target will be built. This is always set, either explicitly, or implicitly when make selects the default target, to give the user a way to refer to the default target on the command line.
.MAKEFLAGS
This target provides a way to specify flags for make when the makefile is used. The flags are as if typed to the shell, though the -f option will have no effect. Flags (except for -f ) and variable assignments specified as the source for this target are also appended to the .MAKEFLAGS internal variable. Please note the difference between this target and the .MAKEFLAGS internal variable: specifying an option or variable assignment as the source for this target will affect both the current makefile and all processes that make executes.
.MFLAGS
Same as above, for backward compatibility.
.NOTPARALLEL
Disable parallel mode.
.NO_PARALLEL
Same as above, for compatibility with other pmake variants.
.ORDER
The named targets are made in sequence.
.PATH
The sources are directories which are to be searched for files not found in the current directory. If no sources are specified, any previously specified directories are deleted. Where possible, use of .PATH is preferred over use of the VPATH variable.
.PATHsuffix
The sources are directories which are to be searched for suffixed files not found in the current directory. The make utility first searches the suffixed search path, before reverting to the default path if the file is not found there. This form is required for .LIBS and .INCLUDES to work.
.PHONY
Apply the .PHONY attribute to any specified sources. Targets with this attribute are always considered to be out of date.
.PRECIOUS
Apply the .PRECIOUS attribute to any specified sources. If no sources are specified, the .PRECIOUS attribute is applied to every target in the file.
.SHELL
Select another shell. The sources of this target have the format key = value. The key is one of:
path
Specify the path to the new shell.
name
Specify the name of the new shell. This may be either one of the three builtin shells (see below) or any other name.
quiet
Specify the shell command to turn echoing off.
echo
Specify the shell command to turn echoing on.
filter
Usually shells print the echo off command before turning echoing off. This is the exact string that will be printed by the shell and is used to filter the shell output to remove the echo off command.
echoFlag
The shell option that turns echoing on.
errFlag
The shell option to turn on error checking. If error checking is on, the shell should exit if a command returns a non-zero status.
hasErrCtl
True if the shell has error control.
check
If hasErrCtl is true then this is the shell command to turn error checking on. If hasErrCtl is false then this is a command template to echo commands for which error checking is disabled. The template must contain a ‘%s’.
ignore
If hasErrCtl is true, this is the shell command to turn error checking off. If hasErrCtl is false, this is a command template to execute a command so that errors are ignored. The template must contain a ‘%s’.
meta
This is a string of meta characters of the shell.
builtins
This is a string holding all the shell’s builtin commands separated by blanks. The meta and builtins strings are used in compat mode. When a command line contains neither a meta character nor starts with a shell builtin, it is executed directly without invoking a shell. When one of these strings (or both) is empty all commands are executed through a shell.
unsetenv
If true, remove the ENV environment variable before executing any command. This is useful for the Korn-shell (ksh).
Values that are strings must be surrounded by double quotes. Boolean values are specified as ‘T’ or ‘Y’ (in either case) to mean true. Any other value is taken to mean false.
There are several uses of the .SHELL target:
Selecting one of the builtin shells. This is done by just specifying the name of the shell with the name keyword. It is also possible to modify the parameters of the builtin shell by just specifying other keywords (except for path).
Using another executable for one of the builtin shells. This is done by specifying the path to the executable with the path keyword. If the last component is the same as the name of the builtin shell, no name needs to be specified; if it is different, the name must be given:
.SHELL: path="/usr/local/bin/sh"
selects the builtin shell "sh" but will execute it from /usr/local/bin/sh. Like in the previous case, it is possible to modify parameters of the builtin shell by just specifying them.
Using an entirely different shell. This is done by specifying all keywords.
The builtin shells are "sh", "csh" and "ksh". Because .Fx has no ksh in /bin, it is unwise to specify name ="ksh" without also specifying a path.
.SILENT
Apply the .SILENT attribute to any specified sources. If no sources are specified, the .SILENT attribute is applied to every command in the file.
.SUFFIXES
Each source specifies a suffix to make. If no sources are specified, any previous specified suffices are deleted.
.WARN
Each source specifies a warning flag as previously described for the -x command line option. Warning flags specified on the command line take precedence over flags specified in the makefile. Also, command line warning flags are pushed to sub-makes through the MAKEFLAGS environment variables so that a warning flag specified on the command line will influence all sub-makes. Several flags can be specified on a single .WARN target by seperating them with blanks.
