NAME
m4 - macro processor
SYNOPSIS
m4 [OPTION]... [FILE]...
DESCRIPTION
Process macros in FILEs. If no FILE or if FILE is ’-’, standard input is read.
Mandatory or optional arguments to long options are mandatory or optional for short options too.
Operation modes:
|
--help |
display this help and exit |
--version
output version information and exit
-E, --fatal-warnings
once: warnings become errors, twice: stop execution at first error
-i, --interactive
unbuffer output, ignore interrupts
-P, --prefix-builtins
force a ’m4_’ prefix to all builtins
-Q, --quiet, --silent
suppress some warnings for builtins
--warn-macro-sequence[=REGEXP]
warn if macro definition matches REGEXP,
default \$\({[^}]*}\|[0-9][0-9]+\)
-W, --word-regexp=REGEXP
use REGEXP for macro name syntax
Preprocessor
features:
-D, --define=NAME[=VALUE]
define NAME as having VALUE, or empty
-I, --include=DIRECTORY
append DIRECTORY to include path
-s, --synclines
generate ’#line NUM "FILE"’ lines
-U, --undefine=NAME
undefine NAME
Limits
control:
-g, --gnu
override -G to re-enable GNU extensions
-G, --traditional
suppress all GNU extensions
-H, --hashsize=PRIME
set symbol lookup hash table size [509]
-L, --nesting-limit=NUMBER
change nesting limit, 0 for unlimited [0]
Frozen state
files:
-F, --freeze-state=FILE
produce a frozen state on FILE at end
-R, --reload-state=FILE
reload a frozen state from FILE at start
Debugging:
-d, --debug[=FLAGS]
set debug level (no FLAGS implies ’aeq’)
--debugfile[=FILE]
redirect debug and trace output to FILE (default stderr, discard if empty string)
-l, --arglength=NUM
restrict macro tracing size
-t, --trace=NAME
trace NAME when it is defined
FLAGS is any of:
|
a |
show actual arguments |
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|
c |
show before collect, after collect and after call |
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|
e |
show expansion |
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|
f |
say current input file name |
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|
i |
show changes in input files |
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|
l |
say current input line number |
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|
p |
show results of path searches |
|||
|
q |
quote values as necessary, with a or e flag |
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|
t |
trace for all macro calls, not only traceon’ed |
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|
x |
add a unique macro call id, useful with c flag |
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|
V |
shorthand for all of the above flags |
If defined, the environment variable ’M4PATH’ is a colon-separated list of directories included after any specified by ’-I’.
Exit status is 0 for success, 1 for failure, 63 for frozen file version mismatch, or whatever value was passed to the m4exit macro.
AUTHOR
Written by Rene’ Seindal.
REPORTING BUGS
Report bugs to:
bug-m4 [AT] gnu.org
GNU M4 home page: <https://www.gnu.org/software/m4/>;
General help using GNU software:
<https://www.gnu.org/gethelp/>;
COPYRIGHT
Copyright
© 2021 Free Software Foundation, Inc. License GPLv3+:
GNU GPL version 3 or later
<https://gnu.org/licenses/gpl.html>;.
This is free software: you are free to change and
redistribute it. There is NO WARRANTY, to the extent
permitted by law.
SEE ALSO
The full documentation for m4 is maintained as a Texinfo manual. If the info and m4 programs are properly installed at your site, the command
info m4
should give you access to the complete manual.