Reproduceable bug - segfault when using -t as last option and an empty filter

[elof2 at sentor.se]

The segfault is reproduceable every time and occur both FreeBSD 7.4 i386 
and amd64.

ARGUS:   Argus Version 3.0.5.5
RA:      Ra Version 3.0.5.19


To generate a segfault, simply run a ra-command with a timerange (-t NN)
option as the last option, then add a trailing dash (-) to separate 
the commandline options from the bpf-like filter, but add no filter.


Three examples:

ra -Zb -nr argus.log -t 15:26:32
no error, I see lots of output.

ra -Zb -nr argus.log -t 15:26:32 -
Segmentation fault: 11 (core dumped)   <-----

ra -Zb -nr argus.log -t 15:26:32 - not ip
no error, I see lots of arp and llc packets.


My guess is that the trailing dash is interpreted as being part of the -t 
timerange and not as a delimiter/separator.

/Elof