M4

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.