[cups.general] shell script as filter -> core dump

[Willi Burmeister]

Hi,

I'm on my way to migrate our old LPRng installation to CUPS. The setup
was easy as all of our printers are network enabled postscript printers.

Now I'm trying to substitute 'texttops' with a filter of my own, as I
want all ASCII files send through 'mp'. For this I wrote a small 
shell script:

----------------------------------------------------------------------
#!/bin/sh

PRINTER=$0
JOB=$1
USER=$2
TITLE=$3
COPIES=$4
OPTIONS=$5
FILENAME=$6

/usr/local/bin/mp -text -landscape -a4 -alias "$USER" \
        -subject " $USER:$TITLE" $FILENAME

exit 0
----------------------------------------------------------------------

and changed the 'text/plain' line in 'mime.convs' to

----------------------------------------------------------------------
text/plain         application/postscript  33      mp_filter
----------------------------------------------------------------------

The script works without problems when called by itself, but does not 
work with cups. Even worse 'cupsd' stopped running after a SIGSEGV.

I searched the net for any information about writing filter for cups,
but could not found anything about shell scripts. Is there something
special to keep in mind? Does anybody have a working shell filter for
cups?

Any help is appreciated.

Thanks

Willi