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.
--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 e$e({[^}]*}e|[0-9][0-9]+e)
-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
-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]
-F, --freeze-state=FILE produce a frozen state on FILE at end
-R, --reload-state=FILE reload a frozen state from FILE at start
-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
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.
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 © 2013 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.
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.