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 \$\({[^}]*}\|[0-9][0-9]+\)
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
c show before collect, after collect and after call
e show expansion
f say current input file name
i show changes in input files
l say current input line number
p show results of path searches
q quote values as necessary, with a or e flag
t trace for all macro calls, not only traceon’ed
x add a unique macro call id, useful with c flag
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@gnu.org GNU M4 home page:
<http://www.gnu.org/software/m4/> General help using GNU software:
<http://www.gnu.org/gethelp/>
COPYRIGHT
Copyright © 2010 Free Software Foundation, Inc. License GPLv3+: GNU
GPL version 3 or later <http://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.