BMAKE
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NAME
bmake
- maintain program dependencies
SYNOPSIS
bmake
[-BeikNnqrstWwX
]
[-C directory
]
[-D variable
]
[-d flags
]
[-f makefile
]
[-I directory
]
[-J private
]
[-j max_jobs
]
[-m directory
]
[-T file
]
[-V variable
]
[-v variable
]
[variable=value
]
[target ...
]
DESCRIPTION
bmake
is a program designed to simplify the maintenance of other programs.
Its input is a list of specifications as to the files upon which programs
and other files depend.
If no
-f makefile
makefile option is given,
bmake
will try to open
`makefile
'
then
`Makefile
'
in order to find the specifications.
If the file
`.depend
'
exists, it is read (see
mkdep(1)).
This manual page is intended as a reference document only.
For a more thorough description of
bmake
and makefiles, please refer to
"PMake - A Tutorial" .
bmake
will prepend the contents of the
MAKEFLAGS
environment variable to the command line arguments before parsing them.
The options are as follows:
- -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.
- -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
bmake
are to print debugging information.
Unless the flags are preceded by
`-'
they are added to the
MAKEFLAGS
environment variable and will be processed by any child make processes.
By default, debugging information is printed to standard error,
but this can be changed using the
F
debugging flag.
The debugging output is always unbuffered; in addition, if debugging
is enabled but debugging output is not directed to standard output,
then the standard output is line buffered.
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 current working directory.
- c
-
Print debugging information about conditional evaluation.
- d
-
Print debugging information about directory searching and caching.
- e
-
Print debugging information about failed commands and targets.
- F [+ filename
]
-
Specify where debugging output is written.
This must be the last flag, because it consumes the remainder of
the argument.
If the character immediately after the
`F'
flag is
`+'
,
then the file will be opened in append mode;
otherwise the file will be overwritten.
If the file name is
`stdout'
or
`stderr'
then debugging output will be written to the
standard output or standard error output file descriptors respectively
(and the
`+'
option has no effect).
Otherwise, the output will be written to the named file.
If the file name ends
`.%d'
then the
`%d'
is replaced by the pid.
- f
-
Print debugging information about loop evaluation.
- g1
-
Print the input graph before making anything.
- g2
-
Print the input graph after making everything, or before exiting
on error.
- g3
-
Print the input graph 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 "meta" mode decisions about targets.
- m
-
Print debugging information about making targets, including modification
dates.
- n
-
Don't delete the temporary command scripts created when running commands.
These temporary scripts are created in the directory
referred to by the
TMPDIR
environment variable, or in
/tmp
if
TMPDIR
is unset or set to the empty string.
The temporary scripts are created by
mkstemp(3),
and have names of the form
makeXXXXXX
NOTE
This can create many files in
TMPDIR
or
/tmp
so use with care.
- p
-
Print debugging information about makefile parsing.
- s
-
Print debugging information about suffix-transformation rules.
- t
-
Print debugging information about target list maintenance.
- V
-
Force the
-V
option to print raw values of variables, overriding the default behavior
set via
.MAKE.EXPAND_VARIABLES
- v
-
Print debugging information about variable assignment.
- x
-
Run shell commands with
-x
so the actual commands are printed as they are executed.
- -e
-
Specify that environment variables override macro assignments within
makefiles.
- -f makefile
-
Specify a makefile to read instead of the default
`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 private
-
This option should
not
be specified by the user.
When the
j
option is in use in a recursive build, this option is passed by a make
to child makes to allow all the make processes in the build to
cooperate to avoid overloading the system.
- -j max_jobs
-
Specify the maximum number of jobs that
bmake
may have running at any one time.
The value is saved in
.MAKE.JOBS
Turns compatibility mode off, unless the
B
flag is also specified.
When compatibility mode is off, all commands associated with a
target are executed in a single shell invocation as opposed to the
traditional one shell invocation per line.
This can break traditional scripts which change directories on each
command invocation and then expect to start with a fresh environment
on the next line.
It is more efficient to correct the scripts rather than turn backwards
compatibility on.
- -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
< file > -style
include statement.
The
-m
option can be used multiple times 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
" file " -style
include statements (see the
-I
option).
If a file or directory name in the
-m
argument (or the
MAKESYSPATH
environment variable) starts with the string
Qq .../
then
bmake
will search for the specified file or directory named in the remaining part
of the argument string.
The search starts with the current directory of
the Makefile and then works upward towards the root of the file system.
If the search is successful, then the resulting directory replaces the
Qq .../
specification in the
-m
argument.
If used, this feature allows
bmake
to easily search in the current source tree for customized sys.mk files
(e.g., by using
Qq .../mk/sys.mk
as an argument).
- -n
-
Display the commands that would have been executed, but do not
actually execute them unless the target depends on the .MAKE special
source (see below).
- -N
-
Display the commands which would have been executed, but do not
actually execute any of them; useful for debugging top-level makefiles
without descending into subdirectories.
- -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
-
Do not echo any commands as they are executed.
Equivalent to specifying
`@
'
before each command line in the makefile.
- -T tracefile
-
When used with the
-j
flag,
append a trace record to
tracefile
for each job started and completed.
- -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 the value of
variable
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.
The value printed is extracted from the global context after all
makefiles have been read.
By default, the raw variable contents (which may
include additional unexpanded variable references) are shown.
If
variable
contains a
`$'
then the value will be recursively expanded to its complete resultant
text before printing.
The expanded value will also be printed if
.MAKE.EXPAND_VARIABLES
is set to true and
the
-dV
option has not been used to override it.
Note that loop-local and target-local variables, as well as values
taken temporarily by global variables during makefile processing, are
not accessible via this option.
The
-dv
debug mode can be used to see these at the cost of generating
substantial extraneous output.
- -v variable
-
Like
-V
but the variable is always expanded to its complete value.
- -W
-
Treat any warnings during makefile parsing as errors.
- -w
-
Print entering and leaving directory messages, pre and post processing.
- -X
-
Don't export variables passed on the command line to the environment
individually.
Variables passed on the command line are still exported
via the
MAKEFLAGS
environment variable.
This option may be useful on systems which have a small limit on the
size of command arguments.
- variable=value
-
Set the value of the variable
variable
to
value
Normally, all values passed on the command line are also exported to
sub-makes in the environment.
The
-X
flag disables this behavior.
Variable assignments should follow options for POSIX compatibility
but no ordering is enforced.
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.
FILE DEPENDENCY SPECIFICATIONS
Dependency lines consist of one or more targets, an operator, and zero
or more sources.
This creates a relationship where the targets
``depend''
on the sources
and are usually created from them.
The exact relationship between the target and the source is determined
by the operator that separates them.
The three operators are as follows:
- :
-
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
bmake
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
bmake
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
bmake
is interrupted.
Targets and sources may contain the shell wildcard values
`?'
,
`*'
,
`[]'
,
and
`{}'
The values
`?'
,
`*'
,
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 value
`{}'
need not necessarily be used to describe existing files.
Expansion is in directory order, not alphabetically as done in the shell.
SHELL COMMANDS
Each target may have associated with it one or more lines of shell
commands, normally
used to create the target.
Each of the lines in this script
must
be preceded by a tab.
(For historical reasons, spaces are not accepted.)
While targets can appear in many dependency lines if desired, by
default only one of these rules may be followed by a creation
script.
If the
`::
'
operator is used, however, all rules may include scripts and the
scripts are executed in the order found.
Each line is treated as a separate shell command, unless the end of
line is escaped with a backslash
(`\'
)
in which case that line and the next are combined.
If the first characters of the command are any combination of
`@
'
,
`+
'
,
or
`-
'
,
the command is treated specially.
A
`@
'
causes the command not to be echoed before it is executed.
A
`+
'
causes the command to be executed even when
-n
is given.
This is similar to the effect of the .MAKE special source,
except that the effect can be limited to a single line of a script.
A
`-
'
in compatibility mode
causes any non-zero exit status of the command line to be ignored.
When
bmake
is run in jobs mode with
-j max_jobs
the entire script for the target is fed to a
single instance of the shell.
In compatibility (non-jobs) mode, each command is run in a separate process.
If the command contains any shell meta characters
(`#=|^(){};&<>*?[]:$`\\n'
)
it will be passed to the shell; otherwise
bmake
will attempt direct execution.
If a line starts with
`-
'
and the shell has ErrCtl enabled then failure of the command line
will be ignored as in compatibility mode.
Otherwise
`-
'
affects the entire job;
the script will stop at the first command line that fails,
but the target will not be deemed to have failed.
Makefiles should be written so that the mode of
bmake
operation does not change their behavior.
For example, any command which needs to use
``cd''
or
``chdir''
without potentially changing the directory for subsequent commands
should be put in parentheses so it executes in a subshell.
To force the use of one shell, escape the line breaks so as to make
the whole script one command.
For example:
avoid-chdir-side-effects:
@echo Building $@ in `pwd`
@(cd ${.CURDIR} && ${MAKE} $@)
@echo Back in `pwd`
ensure-one-shell-regardless-of-mode:
@echo Building $@ in `pwd`; \
(cd ${.CURDIR} && ${MAKE} $@); \
echo Back in `pwd`
Since
bmake
will
chdir(2)
to
`.OBJDIR
'
before executing any targets, each child process
starts with that as its current working directory.
VARIABLE ASSIGNMENTS
Variables in make are much like variables in the shell, and, by tradition,
consist of all upper-case letters.
Variable assignment modifiers
The five operators that can be used to assign values to variables are as
follows:
- =
-
Assign the value to the variable.
Any previous value is overridden.
- +=
-
Append the value to the current value of the variable.
- ?=
-
Assign the value to the variable if it is not already defined.
- :=
-
Assign with expansion, i.e. expand the value before assigning it
to the variable.
Normally, expansion is not done until the variable is referenced.
NOTE
References to undefined variables are
not
expanded.
This can cause problems when variable modifiers are used.
- !=
-
Expand the value and pass it to the shell for execution and assign
the result to the variable.
Any newlines in the result are replaced with spaces.
Any white-space before the assigned
value
is removed; if the value is being appended, a single space is inserted
between the previous contents of the variable and the appended value.
Variables are expanded by surrounding the variable name with either
curly braces
(`{}'
)
or parentheses
(`()'
)
and preceding it with
a dollar sign
(`$'
)
If the variable name contains only a single letter, the surrounding
braces or parentheses are not required.
This shorter form is not recommended.
If the variable name contains a dollar, then the name itself is expanded first.
This allows almost arbitrary variable names, however names containing dollar,
braces, parenthesis, or whitespace are really best avoided!
If the result of expanding a variable contains a dollar sign
(`$'
)
the string is expanded again.
Variable substitution occurs at three 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.
-
``.for''
loop index variables are expanded on each loop iteration.
Note that other variables are not expanded inside loops so
the following example code:
.for i in 1 2 3
a+= ${i}
j= ${i}
b+= ${j}
.endfor
all:
@echo ${a}
@echo ${b}
will print:
1 2 3
3 3 3
Because while ${a} contains
``1 2 3''
after the loop is executed, ${b}
contains
``${j} ${j} ${j}''
which expands to
``3 3 3''
since after the loop completes ${j} contains
``3''
Variable classes
The four different classes of variables (in order of increasing precedence)
are:
- Environment variables
-
Variables defined as part of
's
environment.
- Global variables
-
Variables defined in the makefile or in included makefiles.
- Command line variables
-
Variables defined as part of the command line.
- Local variables
-
Variables that are defined specific to a certain target.
Local variables are all built in and their values vary magically from
target to target.
It is not currently possible to define new local variables.
The seven local variables are as follows:
- .ALLSRC
-
The list of all sources for this target; also known as
`>
'
- .ARCHIVE
-
The name of the archive file; also known as
`!
'
- .IMPSRC
-
In suffix-transformation rules, the name/path of the source from which the
target is to be transformed (the
``implied''
source); also known as
`<
'
It is not defined in explicit rules.
- .MEMBER
-
The name of the archive member; also known as
`%
'
- .OODATE
-
The list of sources for this target that were deemed out-of-date; also
known as
`?
'
- .PREFIX
-
The file prefix of the target, containing only the file portion, no suffix
or preceding directory components; also known as
`*
'
The suffix must be one of the known suffixes declared with
.SUFFIXES
or it will not be recognized.
- .TARGET
-
The name of the target; also known as
`@
'
For compatibility with other makes this is an alias for
.ARCHIVE
in archive member rules.
The shorter forms
`('
Va > ,
`!
'
,
`<
'
,
`%
'
,
`?
'
,
`*
'
,
and
`@
'
)
are permitted for backward
compatibility with historical makefiles and legacy POSIX make and are
not recommended.
Variants of these variables with the punctuation followed immediately by
`D'
or
`F'
,
e.g.
`$(@D)
'
,
are legacy forms equivalent to using the
`:H'
and
`:T'
modifiers.
These forms are accepted for compatibility with
AT&T System
V
makefiles and POSIX but 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
'
Additional built-in variables
In addition,
bmake
sets or knows about the following variables:
- $
-
A single dollar sign
`$'
,
i.e.
`$$'
expands to a single dollar
sign.
- .ALLTARGETS
-
The list of all targets encountered in the Makefile.
If evaluated during
Makefile parsing, lists only those targets encountered thus far.
- .CURDIR
-
A path to the directory where
bmake
was executed.
Refer to the description of
`PWD
'
for more details.
- .INCLUDEDFROMDIR
-
The directory of the file this Makefile was included from.
- .INCLUDEDFROMFILE
-
The filename of the file this Makefile was included from.
- MAKE
-
The name that
bmake
was executed with
(argv[0]
)
For compatibility
bmake
also sets
.MAKE
with the same value.
The preferred variable to use is the environment variable
MAKE
because it is more compatible with other versions of
bmake
and cannot be confused with the special target with the same name.
- .MAKE.DEPENDFILE
-
Names the makefile (default
`.depend
'
)
from which generated dependencies are read.
- .MAKE.EXPAND_VARIABLES
-
A boolean that controls the default behavior of the
-V
option.
If true, variable values printed with
-V
are fully expanded; if false, the raw variable contents (which may
include additional unexpanded variable references) are shown.
- .MAKE.EXPORTED
-
The list of variables exported by
bmake.
- .MAKE.JOBS
-
The argument to the
-j
option.
- .MAKE.JOB.PREFIX
-
If
bmake
is run with
j
then output for each target is prefixed with a token
`---'
target ---
the first part of which can be controlled via
.MAKE.JOB.PREFIX
If
.MAKE.JOB.PREFIX
is empty, no token is printed.
For example:
.MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}]
would produce tokens like
`---make[1234]'
target ---
making it easier to track the degree of parallelism being achieved.
- MAKEFLAGS
-
The environment variable
`MAKEFLAGS
'
may contain anything that
may be specified on
's
command line.
Anything specified on
's
command line is appended to the
`MAKEFLAGS
'
variable which is then
entered into the environment for all programs which
bmake
executes.
- .MAKE.LEVEL
-
The recursion depth of
bmake.
The initial instance of
bmake
will be 0, and an incremented value is put into the environment
to be seen by the next generation.
This allows tests like:
.if ${.MAKE.LEVEL} == 0
to protect things which should only be evaluated in the initial instance of
bmake.
- .MAKE.MAKEFILE_PREFERENCE
-
The ordered list of makefile names
(default
`makefile
'
,
`Makefile
'
)
that
bmake
will look for.
- .MAKE.MAKEFILES
-
The list of makefiles read by
bmake,
which is useful for tracking dependencies.
Each makefile is recorded only once, regardless of the number of times read.
- .MAKE.MODE
-
Processed after reading all makefiles.
Can affect the mode that
bmake
runs in.
It can contain a number of keywords:
- compat
-
Like
-B
puts
bmake
into "compat" mode.
- meta
-
Puts
bmake
into "meta" mode, where meta files are created for each target
to capture the command run, the output generated and if
filemon(4)
is available, the system calls which are of interest to
bmake.
The captured output can be very useful when diagnosing errors.
- curdirOk= bf
-
Normally
bmake
will not create .meta files in
`.CURDIR
'
This can be overridden by setting
bf
to a value which represents True.
- missing-meta= bf
-
If
bf
is True, then a missing .meta file makes the target out-of-date.
- missing-filemon= bf
-
If
bf
is True, then missing filemon data makes the target out-of-date.
- nofilemon
-
Do not use
filemon(4).
- env
-
For debugging, it can be useful to include the environment
in the .meta file.
- verbose
-
If in "meta" mode, print a clue about the target being built.
This is useful if the build is otherwise running silently.
The message printed the value of:
.MAKE.META.PREFIX
- ignore-cmd
-
Some makefiles have commands which are simply not stable.
This keyword causes them to be ignored for
determining whether a target is out of date in "meta" mode.
See also
.NOMETA_CMP
- silent= bf
-
If
bf
is True, when a .meta file is created, mark the target
.SILENT
- .MAKE.META.BAILIWICK
-
In "meta" mode, provides a list of prefixes which
match the directories controlled by
bmake.
If a file that was generated outside of
.OBJDIR
but within said bailiwick is missing,
the current target is considered out-of-date.
- .MAKE.META.CREATED
-
In "meta" mode, this variable contains a list of all the meta files
updated.
If not empty, it can be used to trigger processing of
.MAKE.META.FILES
- .MAKE.META.FILES
-
In "meta" mode, this variable contains a list of all the meta files
used (updated or not).
This list can be used to process the meta files to extract dependency
information.
- .MAKE.META.IGNORE_PATHS
-
Provides a list of path prefixes that should be ignored;
because the contents are expected to change over time.
The default list includes:
`/dev
'
/etc /proc /tmp /var/run /var/tmp
- .MAKE.META.IGNORE_PATTERNS
-
Provides a list of patterns to match against pathnames.
Ignore any that match.
- .MAKE.META.IGNORE_FILTER
-
Provides a list of variable modifiers to apply to each pathname.
Ignore if the expansion is an empty string.
- .MAKE.META.PREFIX
-
Defines the message printed for each meta file updated in "meta verbose" mode.
The default value is:
Building ${.TARGET:H:tA}/${.TARGET:T}
- .MAKEOVERRIDES
-
This variable is used to record the names of variables assigned to
on the command line, so that they may be exported as part of
`MAKEFLAGS
'
This behavior can be disabled by assigning an empty value to
`.MAKEOVERRIDES
'
within a makefile.
Extra variables can be exported from a makefile
by appending their names to
`.MAKEOVERRIDES
'
`MAKEFLAGS
'
is re-exported whenever
`.MAKEOVERRIDES
'
is modified.
- .MAKE.PATH_FILEMON
-
If
bmake
was built with
filemon(4)
support, this is set to the path of the device node.
This allows makefiles to test for this support.
- .MAKE.PID
-
The process-id of
bmake.
- .MAKE.PPID
-
The parent process-id of
bmake.
- .MAKE.SAVE_DOLLARS
-
value should be a boolean that controls whether
`$$'
are preserved when doing
`:='
assignments.
The default is false, for backwards compatibility.
Set to true for compatability with other makes.
If set to false,
`$$'
becomes
`$'
per normal evaluation rules.
- MAKE_PRINT_VAR_ON_ERROR
-
When
bmake
stops due to an error, it sets
`.ERROR_TARGET
'
to the name of the target that failed,
`.ERROR_CMD
'
to the commands of the failed target,
and in "meta" mode, it also sets
`.ERROR_CWD
'
to the
getcwd(3),
and
`.ERROR_META_FILE
'
to the path of the meta file (if any) describing the failed target.
It then prints its name and the value of
`.CURDIR
'
as well as the value of any variables named in
`MAKE_PRINT_VAR_ON_ERROR
'
- .newline
-
This variable is simply assigned a newline character as its value.
This allows expansions using the
:@
modifier to put a newline between
iterations of the loop rather than a space.
For example, the printing of
`MAKE_PRINT_VAR_ON_ERROR
'
could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}.
- .OBJDIR
-
A path to the directory where the targets are built.
Its value is determined by trying to
chdir(2)
to the following directories in order and using the first match:
-
${MAKEOBJDIRPREFIX}${.CURDIR}
(Only if
`MAKEOBJDIRPREFIX
'
is set in the environment or on the command line.)
-
${MAKEOBJDIR}
(Only if
`MAKEOBJDIR
'
is set in the environment or on the command line.)
-
${.CURDIR} /obj. ${MACHINE}
-
${.CURDIR} /obj
-
/usr/obj/ ${.CURDIR}
-
${.CURDIR}
Variable expansion is performed on the value before it's used,
so expressions such as
${.CURDIR:S,^/usr/src,/var/obj,}
may be used.
This is especially useful with
`MAKEOBJDIR
'
`.OBJDIR
'
may be modified in the makefile via the special target
`.OBJDIR
'
In all cases,
bmake
will
chdir(2)
to the specified directory if it exists, and set
`.OBJDIR
'
and
`PWD
'
to that directory before executing any targets.
- .PARSEDIR
-
A path to the directory of the current
`Makefile
'
being parsed.
- .PARSEFILE
-
The basename of the current
`Makefile
'
being parsed.
This variable and
`.PARSEDIR
'
are both set only while the
`Makefiles
'
are being parsed.
If you want to retain their current values, assign them to a variable
using assignment with expansion:
(`:=
'
)
- .PATH
-
A variable that represents the list of directories that
bmake
will search for files.
The search list should be updated using the target
`.PATH
'
rather than the variable.
- PWD
-
Alternate path to the current directory.
bmake
normally sets
`.CURDIR
'
to the canonical path given by
getcwd(3).
However, if the environment variable
`PWD
'
is set and gives a path to the current directory, then
bmake
sets
`.CURDIR
'
to the value of
`PWD
'
instead.
This behavior is disabled if
`MAKEOBJDIRPREFIX
'
is set or
`MAKEOBJDIR
'
contains a variable transform.
`PWD
'
is set to the value of
`.OBJDIR
'
for all programs which
bmake
executes.
- .TARGETS
-
The list of targets explicitly specified on the command line, if any.
- VPATH
-
Colon-separated
(``:''
)
lists of directories that
bmake
will search for files.
The variable is supported for compatibility with old make programs only,
use
`.PATH
'
instead.
Variable modifiers
Variable expansion may be modified to select or modify each word of the
variable (where a
``word''
is white-space delimited sequence of characters).
The general format of a variable expansion is as follows:
${variable[:modifier[:...]]}
Each modifier begins with a colon,
which may be escaped with a backslash
(`\'
)
A set of modifiers can be specified via a variable, as follows:
modifier_variable=modifier[:...]
${variable:${modifier_variable}[:...]}
In this case the first modifier in the modifier_variable does not
start with a colon, since that must appear in the referencing
variable.
If any of the modifiers in the modifier_variable contain a dollar sign
(`$'
)
these must be doubled to avoid early expansion.
The supported modifiers are:
- :E
-
Replaces each word in the variable with its suffix.
- :H
-
Replaces each word in the variable with everything but the last component.
- :M pattern
-
Select only those words that match
pattern
The standard shell wildcard characters
( `*'
`?'
,
and
`[]
'
may
be used.
The wildcard characters may be escaped with a backslash
(`\'
)
As a consequence of the way values are split into words, matched,
and then joined, a construct like
${VAR:M*}
will normalize the inter-word spacing, removing all leading and
trailing space, and converting multiple consecutive spaces
to single spaces.
- :N pattern
-
This is identical to
`:M
'
,
but selects all words which do not match
pattern
- :O
-
Order every word in variable alphabetically.
- :Order every word in variable in reverse alphabetical order.
-
- :Ox Randomize words in variable.
-
The results will be different each time you are referring to the
modified variable; use the assignment with expansion
(`:=
'
)
to prevent such behavior.
For example,
LIST= uno due tre quattro
RANDOM_LIST= ${LIST:Ox}
STATIC_RANDOM_LIST:= ${LIST:Ox}
all:
@echo "${RANDOM_LIST}"
@echo "${RANDOM_LIST}"
@echo "${STATIC_RANDOM_LIST}"
@echo "${STATIC_RANDOM_LIST}"
may produce output similar to:
quattro due tre uno
tre due quattro uno
due uno quattro tre
due uno quattro tre
- :Q
-
Quotes every shell meta-character in the variable, so that it can be passed
safely to the shell.
- :q
-
Quotes every shell meta-character in the variable, and also doubles
`$'
characters so that it can be passed
safely through recursive invocations of
bmake.
This is equivalent to:
`:S/\$/&&/g:Q'
- :R
-
Replaces each word in the variable with everything but its suffix.
- :range[=count]
-
The value is an integer sequence representing the words of the original
value, or the supplied
count
- :gmtime[=utc]
-
The value is a format string for
strftime(3),
using
gmtime(3).
If a
utc
value is not provided or is 0, the current time is used.
- :hash
-
Compute a 32-bit hash of the value and encode it as hex digits.
- :localtime[=utc]
-
The value is a format string for
strftime(3),
using
localtime(3).
If a
utc
value is not provided or is 0, the current time is used.
- :tA
-
Attempt to convert variable to an absolute path using
realpath(3),
if that fails, the value is unchanged.
- :tl
-
Converts variable to lower-case letters.
- :ts c
-
Words in the variable are normally separated by a space on expansion.
This modifier sets the separator to the character
c
If
c
is omitted, then no separator is used.
The common escapes (including octal numeric codes), work as expected.
- :tu
-
Converts variable to upper-case letters.
- :tW
-
Causes the value to be treated as a single word
(possibly containing embedded white space).
See also
`:[*]
'
- :tw
-
Causes the value to be treated as a sequence of
words delimited by white space.
See also
`:[@]
'
- :S / old_string / new_string / [1gW
]
-
Modify the first occurrence of
old_string
in 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 a
`1'
is appended to the last slash of the pattern, only the first word
is affected.
If a
`W'
is appended to the last slash of the pattern,
then the value is treated as a single word
(possibly containing embedded white space).
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
(without any
`^'
or
`$'
) .
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.
- :C / pattern / replacement / [1gW
]
-
The
:C
modifier is just like the
:S
modifier except that the old and new strings, instead of being
simple strings, are an extended regular expression (see
regex(3))
string
pattern
and an
ed(1)Ns-style
string
replacement
Normally, the first occurrence of the pattern
pattern
in each word of the value is substituted with
replacement
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
pattern
as occur in the word or words it is found in; the
`W'
modifier causes the value to be treated as a single word
(possibly containing embedded white space).
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.
As for the
:S
modifier, the
pattern
and
replacement
are subjected to variable expansion before being parsed as
regular expressions.
- :T
-
Replaces each word in the variable with its last component.
- :u
-
Remove adjacent duplicate words (like
uniq(1)).
- :? true_string : false_string
-
If the variable name (not its value), when parsed as a .if conditional
expression, evaluates to true, return as its value the
true_string
otherwise return the
false_string
Since the variable name is used as the expression, :? must be the
first modifier after the variable name itself - which will, of course,
usually contain variable expansions.
A common error is trying to use expressions like
${NUMBERS:M42:?match:no}
which actually tests defined(NUMBERS),
to determine is any words match "42" you need to use something like:
${"${NUMBERS:M42}" != "":?match:no}
- :old_string=new_string
-
This is the
AT&T System
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
If only
old_string
contains the pattern matching character
%
and
old_string
matches, then the result is the
new_string
If only the
new_string
contains the pattern matching character
%
then it is not treated specially and it is printed as a literal
%
on match.
If there is more than one pattern matching character
( %
in either the
new_string
or
old_string
only the first instance is treated specially (as the pattern character);
all subsequent instances are treated as regular characters
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.
- :@ temp @ string @
-
This is the loop expansion mechanism from the OSF Development
Environment (ODE) make.
Unlike
.for
loops expansion occurs at the time of
reference.
Assign
temp
to each word in the variable and evaluate
string
The ODE convention is that
temp
should start and end with a period.
For example.
${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
However a single character variable is often more readable:
${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}
- :_[=var]
-
Save the current variable value in
`$_'
or the named
var
for later reference.
Example usage:
M_cmpv.units = 1 1000 1000000
M_cmpv = S,., ,g:_:range:@i@+ $${_:[-$$i]} \
\* $${M_cmpv.units:[$$i]}@:S,^,expr 0 ,1:sh
.if ${VERSION:${M_cmpv}} < ${3.1.12:L:${M_cmpv}}
Here
`$_'
is used to save the result of the
`:S'
modifier which is later referenced using the index values from
`:range'
- :U newval
-
If the variable is undefined
newval
is the value.
If the variable is defined, the existing value is returned.
This is another ODE make feature.
It is handy for setting per-target CFLAGS for instance:
${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
If a value is only required if the variable is undefined, use:
${VAR:D:Unewval}
- :D newval
-
If the variable is defined
newval
is the value.
- :L
-
The name of the variable is the value.
- :P
-
The path of the node which has the same name as the variable
is the value.
If no such node exists or its path is null, then the
name of the variable is used.
In order for this modifier to work, the name (node) must at least have
appeared on the rhs of a dependency.
- :! cmd !
-
The output of running
cmd
is the value.
- :sh
-
If the variable is non-empty it is run as a command and the output
becomes the new value.
- ::= str
-
The variable is assigned the value
str
after substitution.
This modifier and its variations are useful in
obscure situations such as wanting to set a variable when shell commands
are being parsed.
These assignment modifiers always expand to
nothing, so if appearing in a rule line by themselves should be
preceded with something to keep
bmake
happy.
The
`::
'
helps avoid false matches with the
AT&T System
V
style
:=
modifier and since substitution always occurs the
::=
form is vaguely appropriate.
- ::?= str
-
As for
::=
but only if the variable does not already have a value.
- ::+= str
-
Append
str
to the variable.
- ::!= cmd
-
Assign the output of
cmd
to the variable.
- :[ range ]
-
Selects one or more words from the value,
or performs other operations related to the way in which the
value is divided into words.
Ordinarily, a value is treated as a sequence of words
delimited by white space.
Some modifiers suppress this behavior,
causing a value to be treated as a single word
(possibly containing embedded white space).
An empty value, or a value that consists entirely of white-space,
is treated as a single word.
For the purposes of the
`:[]
'
modifier, the words are indexed both forwards using positive integers
(where index 1 represents the first word),
and backwards using negative integers
(where index -1 represents the last word).
The
range
is subjected to variable expansion, and the expanded result is
then interpreted as follows:
- index
-
Selects a single word from the value.
- start .. end
-
Selects all words from
start
to
end
inclusive.
For example,
`:[2..-1]
'
selects all words from the second word to the last word.
If
start
is greater than
end
then the words are output in reverse order.
For example,
`:[-1..1]
'
selects all the words from last to first.
If the list is already ordered, then this effectively reverses
the list, but it is more efficient to use
`:instead
'
of
`:O:[-1..1]
'
- *
-
Causes subsequent modifiers to treat the value as a single word
(possibly containing embedded white space).
Analogous to the effect of
"$*"
in Bourne shell.
- 0
-
Means the same as
`:[*]
'
- @
-
Causes subsequent modifiers to treat the value as a sequence of words
delimited by white space.
Analogous to the effect of
"$@"
in Bourne shell.
- #
-
Returns the number of words in the value.
INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS
Makefile inclusion, conditional structures and for loops reminiscent
of the C programming language are provided in
bmake.
All such structures are identified by a line beginning with a single
dot
(`.'
)
character.
Files are included with either
.include < file >
or
.include " file "
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.
For compatibility with other versions of
bmake
`include'
file ...
is also accepted.
If the include statement is written as
.-include
or as
.sinclude
then errors locating and/or opening include files are ignored.
If the include statement is written as
.dinclude
not only are errors locating and/or opening include files ignored,
but stale dependencies within the included file will be ignored
just like
.MAKE.DEPENDFILE
Conditional expressions are also preceded by a single dot as the first
character of a line.
The possible conditionals are as follows:
- .error message
-
The message is printed along with the name of the makefile and line number,
then
bmake
will exit.
- .export variable ...
-
Export the specified global variable.
If no variable list is provided, all globals are exported
except for internal variables (those that start with
`.'
) .
This is not affected by the
-X
flag, so should be used with caution.
For compatibility with other
bmake
programs
`export'
variable=value
is also accepted.
Appending a variable name to
.MAKE.EXPORTED
is equivalent to exporting a variable.
- .export-env variable ...
-
The same as
`.export'
,
except that the variable is not appended to
.MAKE.EXPORTED
This allows exporting a value to the environment which is different from that
used by
bmake
internally.
- .export-literal variable ...
-
The same as
`.export-env'
,
except that variables in the value are not expanded.
- .info message
-
The message is printed along with the name of the makefile and line number.
- .undef variable
-
Un-define the specified global variable.
Only global variables may be un-defined.
- .unexport variable ...
-
The opposite of
`.export'
The specified global
variable
will be removed from
.MAKE.EXPORTED
If no variable list is provided, all globals are unexported,
and
.MAKE.EXPORTED
deleted.
- .unexport-env
-
Unexport all globals previously exported and
clear the environment inherited from the parent.
This operation will cause a memory leak of the original environment,
so should be used sparingly.
Testing for
.MAKE.LEVEL
being 0, would make sense.
Also note that any variables which originated in the parent environment
should be explicitly preserved if desired.
For example:
.if ${.MAKE.LEVEL} == 0
PATH := ${PATH}
.unexport-env
.export PATH
.endif
Would result in an environment containing only
`PATH
'
,
which is the minimal useful environment.
Actually
`.MAKE.LEVEL
'
will also be pushed into the new environment.
- .warning message
-
The message prefixed by
`warning:
'
is printed along with the name of the makefile and line number.
- .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,
bmake
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.
- commands
-
Takes a target name as an argument and evaluates to true if the target
has been defined and has commands associated with it.
Expression
may also be an arithmetic or string comparison.
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 or an empty string in the case
of a string comparison.
When
bmake
is evaluating one of these conditional expressions, and it encounters
a (white-space separated) word it doesn't recognize, either the
``make''
or
``defined''
expression is applied to it, depending on the form of the conditional.
If the form is
`.ifdef
'
,
`.ifndef
'
,
or
`.if
'
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 [variable ... in expression
]
-
- Aq make-rules
-
- .endfor
-
After the for
expression
is evaluated, it is split into words.
On each iteration of the loop, one word is taken and assigned to each
variable
in order, and these
variables
are substituted into the
make-rules
inside the body of the for loop.
The number of words must come out even; that is, if there are three
iteration variables, the number of words provided must be a multiple
of three.
COMMENTS
Comments begin with a hash
(`#'
)
character, anywhere but in a shell
command line, and continue to the end of an unescaped new line.
SPECIAL SOURCES (ATTRIBUTES)
- .EXEC
-
Target is never out of date, but always execute commands anyway.
- .IGNORE
-
Ignore any errors from the commands associated with this target, exactly
as if they all were preceded by a dash
(`-'
)
- .MADE
-
Mark all sources of this target as being up-to-date.
- .MAKE
-
Execute the commands associated with this target even if the
-n
or
-t
options were specified.
Normally used to mark recursive
s
- .META
-
Create a meta file for the target, even if it is flagged as
.PHONY
.MAKE
or
.SPECIAL
Usage in conjunction with
.MAKE
is the most likely case.
In "meta" mode, the target is out-of-date if the meta file is missing.
- .NOMETA
-
Do not create a meta file for the target.
Meta files are also not created for
.PHONY
.MAKE
or
.SPECIAL
targets.
- .NOMETA_CMP
-
Ignore differences in commands when deciding if target is out of date.
This is useful if the command contains a value which always changes.
If the number of commands change, though, the target will still be out of date.
The same effect applies to any command line that uses the variable
.OODATE
which can be used for that purpose even when not otherwise needed or desired:
skip-compare-for-some:
@echo this will be compared
@echo this will not ${.OODATE:M.NOMETA_CMP}
@echo this will also be compared
The
:M
pattern suppresses any expansion of the unwanted variable.
- .NOPATH
-
Do not search for the target in the directories specified by
.PATH
- .NOTMAIN
-
Normally
bmake
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
bmake
can't figure out how to create it, it will ignore this fact and assume
the file isn't needed or already exists.
- .PHONY
-
The target does not
correspond to an actual file; it is always considered to be out of date,
and will not be created with the
-t
option.
Suffix-transformation rules are not applied to
.PHONY
targets.
- .PRECIOUS
-
When
bmake
is interrupted, it normally removes any partially made targets.
This source prevents the target from being removed.
- .RECURSIVE
-
Synonym for
.MAKE
- .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.
- .USEBEFORE
-
Exactly like
.USE
but prepend the
.USEBEFORE
target commands to the target.
- .WAIT
-
If
.WAIT
appears in a dependency line, the sources that precede it are
made before the sources that succeed it in the line.
Since the dependents of files are not made until the file itself
could be made, this also stops the dependents being built unless they
are needed for another branch of the dependency tree.
So given:
x: a .WAIT b
echo x
a:
echo a
b: b1
echo b
b1:
echo b1
the output is always
`a'
,
`b1'
,
`b'
,
`x'
The ordering imposed by
.WAIT
is only relevant for parallel makes.
SPECIAL TARGETS
Special targets may not be included with other targets, i.e. they must be
the only target specified.
- .BEGIN
-
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
bmake
can't 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.
- .DELETE_ON_ERROR
-
If this target is present in the makefile, it globally causes make to
delete targets whose commands fail.
(By default, only targets whose commands are interrupted during
execution are deleted.
This is the historical behavior.)
This setting can be used to help prevent half-finished or malformed
targets from being left around and corrupting future rebuilds.
- .END
-
Any command lines attached to this target are executed after everything
else is done.
- .ERROR
-
Any command lines attached to this target are executed when another target fails.
The
.ERROR_TARGET
variable is set to the target that failed.
See also
MAKE_PRINT_VAR_ON_ERROR
- .IGNORE
-
Mark each of the sources with the
.IGNORE
attribute.
If no sources are specified, this is the equivalent of specifying the
-i
option.
- .INTERRUPT
-
If
bmake
is interrupted, the commands for this target will be executed.
- .MAIN
-
If no target is specified when
bmake
is invoked, this target will be built.
- .MAKEFLAGS
-
This target provides a way to specify flags for
bmake
when the makefile is used.
The flags are as if typed to the shell, though the
-f
option will have
no effect.
- .NOPATH
-
Apply the
.NOPATH
attribute to any specified sources.
- .NOTPARALLEL
-
Disable parallel mode.
- .NO_PARALLEL
-
Synonym for
.NOTPARALLEL
for compatibility with other pmake variants.
- .OBJDIR
-
The source is a new value for
`.OBJDIR
'
If it exists,
bmake
will
chdir(2)
to it and update the value of
`.OBJDIR
'
- .ORDER
-
The named targets are made in sequence.
This ordering does not add targets to the list of targets to be made.
Since the dependents of a target do not get built until the target itself
could be built, unless
`a'
is built by another part of the dependency graph,
the following is a dependency loop:
.ORDER: b a
b: a
The ordering imposed by
.ORDER
is only relevant for parallel makes.
- .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.
If the source is the special
.DOTLAST
target, then the current working
directory is searched last.
- .PATH. suffix
-
Like
.PATH
but applies only to files with a particular suffix.
The suffix must have been previously declared with
.SUFFIXES
- .PHONY
-
Apply the
.PHONY
attribute to any specified sources.
- .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
-
Sets the shell that
bmake
will use to execute commands.
The sources are a set of
field=value
pairs.
- name
-
This is the minimal specification, used to select one of the built-in
shell specs;
sh
ksh
and
csh
- path
-
Specifies the path to the shell.
- hasErrCtl
-
Indicates whether the shell supports exit on error.
- check
-
The command to turn on error checking.
- ignore
-
The command to disable error checking.
- echo
-
The command to turn on echoing of commands executed.
- quiet
-
The command to turn off echoing of commands executed.
- filter
-
The output to filter after issuing the
quiet
command.
It is typically identical to
quiet
- errFlag
-
The flag to pass the shell to enable error checking.
- echoFlag
-
The flag to pass the shell to enable command echoing.
- newline
-
The string literal to pass the shell that results in a single newline
character when used outside of any quoting characters.
Example:
.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \
check="set -e" ignore="set +e" \
echo="set -v" quiet="set +v" filter="set +v" \
echoFlag=v errFlag=e newline="'\n'"
- .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.
- .STALE
-
This target gets run when a dependency file contains stale entries, having
.ALLSRC
set to the name of that dependency file.
- .SUFFIXES
-
Each source specifies a suffix to
bmake.
If no sources are specified, any previously specified suffixes are deleted.
It allows the creation of suffix-transformation rules.
Example:
.SUFFIXES: .o
.c.o:
cc -o ${.TARGET} -c ${.IMPSRC}
ENVIRONMENT
bmake
uses the following environment variables, if they exist:
MACHINE
MACHINE_ARCH
MACHINE_MULTIARCH
MAKE
MAKEFLAGS
MAKEOBJDIR
MAKEOBJDIRPREFIX
MAKESYSPATH
PWD
and
TMPDIR
MAKEOBJDIRPREFIX
and
MAKEOBJDIR
may only be set in the environment or on the command line to
bmake
and not as makefile variables;
see the description of
`.OBJDIR
'
for more details.
FILES
- .depend
-
list of dependencies
- Makefile
-
list of dependencies
- makefile
-
list of dependencies
- sys.mk
-
system makefile
- /usr/share/mk
-
system makefile directory
COMPATIBILITY
The basic make syntax is compatible between different versions of make;
however the special variables, variable modifiers and conditionals are not.
Older versions
An incomplete list of changes in older versions of
bmake:
The way that .for loop variables are substituted changed after
NetBSD 5.0
so that they still appear to be variable expansions.
In particular this stops them being treated as syntax, and removes some
obscure problems using them in .if statements.
The way that parallel makes are scheduled changed in
NetBSD 4.0
so that .ORDER and .WAIT apply recursively to the dependent nodes.
The algorithms used may change again in the future.
Other make dialects
Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not
support most of the features of
bmake
as described in this manual.
Most notably:
-
The
.WAIT
and
.ORDER
declarations and most functionality pertaining to parallelization.
(GNU make supports parallelization but lacks these features needed to
control it effectively.)
-
Directives, including for loops and conditionals and most of the
forms of include files.
(GNU make has its own incompatible and less powerful syntax for
conditionals.)
-
All built-in variables that begin with a dot.
-
Most of the special sources and targets that begin with a dot,
with the notable exception of
.PHONY
.PRECIOUS
and
.SUFFIXES
-
Variable modifiers, except for the
:old=new
string substitution, which does not portably support globbing with
`%'
and historically only works on declared suffixes.
-
The
$>
variable even in its short form; most makes support this functionality
but its name varies.
Some features are somewhat more portable, such as assignment with
+=
?=
and
!=
The
.PATH
functionality is based on an older feature
VPATH
found in GNU make and many versions of SVR4 make; however,
historically its behavior is too ill-defined (and too buggy) to rely
upon.
The
$@
and
$<
variables are more or less universally portable, as is the
$(MAKE)
variable.
Basic use of suffix rules (for files only in the current directory,
not trying to chain transformations together, etc.) is also reasonably
portable.
SEE ALSO
mkdep(1)
HISTORY
bmake
is derived from NetBSD
make(1).
It uses autoconf to facilitate portability to other platforms.
A
make
command appeared in
AT&T System
v7 .
This
make
implementation is based on Adam De Boor's pmake program which was written
for Sprite at Berkeley.
It was designed to be a parallel distributed make running jobs on different
machines using a daemon called
``customs''
Historically the target/dependency
``FRC''
has been used to FoRCe rebuilding (since the target/dependency
does not exist... unless someone creates an
``FRC''
file).
BUGS
The
make
syntax is difficult to parse without actually acting on the data.
For instance, finding the end of a variable's use should involve scanning
each of the modifiers, using the correct terminator for each field.
In many places
make
just counts {} and () in order to find the end of a variable expansion.
There is no way of escaping a space character in a filename.
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- FILE DEPENDENCY SPECIFICATIONS
-
- SHELL COMMANDS
-
- VARIABLE ASSIGNMENTS
-
- Variable assignment modifiers
-
- Variable classes
-
- Additional built-in variables
-
- Variable modifiers
-
- INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS
-
- COMMENTS
-
- SPECIAL SOURCES (ATTRIBUTES)
-
- SPECIAL TARGETS
-
- ENVIRONMENT
-
- FILES
-
- COMPATIBILITY
-
- Older versions
-
- Other make dialects
-
- SEE ALSO
-
- HISTORY
-
- BUGS
-
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Time: 14:34:53 GMT, April 28, 2024