problems with a C script, exiting with signal 10

[Jordi Moles Blanco]

Hi,

I've got this home-made script, written in C, on a  Freebsd 7.0 server 
with different versions of postfix: 2.3,2,4 and 2.5

The problem is that, while most of the time it works like a charm, 
sometimes it crashes and bounces the message. It's not really a big 
deal, cause the sender gets notified that their mail wasn't delivered 
and hopefully, they will resend it. However, the problem is that I've 
tried to debug my script but found nothing wrong at all, cause it only 
fails from time to time, let's say... once for each 2000 messages that 
postfix receives, and it appears to do so in a random way.

As i said... postfix can fail to deliver a message to one particular 
mailbox, but if then you resend the very same message to the very same 
mailbox, it will be delivered.

The error is reported in both "maillog" and "messages", like this:


******/var/log/maillog********
Aug  7 01:55:19 mail01 postfix/pipe[27534]: 3E1A0143709: 
to=<EMAIL_ACCOUNT>, relay=quota_postfix, delay=0.23, 
delays=0.11/0/0/0.11, dsn=5.3.0, status=bounced (Command died with 
signal 10: "/usr/local/etc/postfix/quota_postfix")


*****/var/log/messages*******
Aug  7 01:55:19 mail01 kernel: pid 29535 (quota_postfix), uid 125: 
exited on signal 10


Here you have some extra information about the script itself and the 
master.cf


*****/usr/local/etc/postfix/quota_postfix***

# ls -la /usr/local/etc/postfix/quota_postfix
-rwsr-xr-x  1 postfix  postfix  20048 Aug  4 10:18 
/usr/local/etc/postfix/quota_postfix

It's got de suid flag cause it performs a "du" command and other file 
operations which need permissions, although i've tried with other groups 
of permissions and it eventually crashes anyway with "signal 10"

******master.cf*********

.........

# spamfilter
spamfilter      unix    -       n       n       -       20      pipe
flags=R user=filter argv=/home/antispam.pl "localhost:10027" "antispam" 
"${sender}" "${recipient}" "/usr/local/bin/spamc"

# from spamfilter to smtpd:10026
localhost:10027 inet    n       -       n       -       100       smtpd 
-o content_filter=quota_postfix


# quota_postfix
quota_postfix      unix    -       n       n       -       20      pipe
flags=R user=filter argv=/usr/local/etc/postfix/quota_postfix 
"localhost" "10028" "${sender}" "${recipient}" "${domain}"

# from quota_postfix to smtpd:10028
localhost:10028 inet    n       -       n       -       100       smtpd 
-o content_filter=

................

So far, any program which crashed would leave a ".core" file in 
/usr/crash, but this one is not doing the same, so... i can't actually 
debug from the core file either.
Sysctl in my FreeBSD server is ok, but i guess that postfix, somehow is 
preventing this filter from generating a core file. Is that possible? Or 
am i completely wrong?

How could I, at least, generate the .core file?

Thanks.