.\" @(#)gpm.6 1.0 93/02/12 
.TH GPM 1 "12 Februari 1993"
.SH NAME
gpm \- general purpose macro filter
.SH SYNOPSIS
.B /vol/practica/m2/bin/gpm
[
.BI -S " stack-size"
]
[
.BI -s " 'specials'"
]
[
.BI -o " out-file"
]
.IR in-file ...

.B /vol/practica/m2/bin/gpmdb

.SH DESCRIPTION
.LP
.B gpm
is a general purpose filter that 
replaces 
.B "gpm macros"
in its input with their expansions.

.SH USAGE
gpm accepts
text from a pipeline, through a redirected file
or from the keyboard. Additionally, gpm can
be given a number of
.I in-files
which it will process in the order they are listed in.
.B gpm
sends its output to stdout, so it can be redirected.
Alternately, a file can be specified
with
.RI "-o" " out-file"
to which gpm will send its output.

.LP
.RS
.nf
.ft B
example% gpm < foo.c

example% cat foo.c | gpm > foo.gpm

example% cat *.c | gpm -o foo.gpm

example% gpm -o foo.gpm *.c
.ft P
.fi
.RE
.LP

.B gpm
works with an internal stack. It is possible that deeply nested macros
or lengthy recursion will cause the stack to overflow. In that
case
.B gpm
prints an error message and exits. The
.B -S
flag allows you to specify a specific stack size. The default
size is 50000.

.LP
.RS
.nf
.ft B
example% gpm -S 43000 ; echo Very big stack

example% gpm -S 100 ; echo Teeny-Tiny stack
.ft P
.fi
.RE
.LP


.B gpm 
understands a certain language  which is composed of 8
special characters. These default to 
.B {|<~>}`\\.
The characters can be changed with the
.B -s
flag. There must be exactly 8 characters in the string
after the
.B -s
flag. These then become the special characters for 
.B gpm.
Note that the special characters should be escaped for the shell.

.LP
.RS
.nf
.ft B
example% gpm -s \[\,\`\~\'\]\\\&

example% gpm -s abcdefgh
.ft P
.fi
.RE
.LP


.SH BUGS
The gpm code itself is ugly as sin.
If
.B you
can understand the error messages,
drop me a line.

.SH AUTHORS
You think anyone's gonna own
up to this one?
.B NOT!
C. Strachey designed and implemented the original
.B gpm,
this is a completely different implementation.

.SH SEE ALSO

gpm(5), gpmdb(5)

/vol/practica/m2/Public/gpm.dvi or gpm.ps