Re: [rdiff-backup-users] RDIFF-F!CKUP (Very frusttrated)

[Charles Duffy]

Golden Butler wrote:
> I'm still relatively a newbie to linux even though I've been using it 
> for almost two years, so excuse me for the ignorance.  What is "strace", 
> and how would I be able to use to track down this segfault problem?

strace shows a program's syscalls -- roughly, the requests it's made to 
the operating system. This will show you exactly what the program was 
trying to do (so long it was something that it had to ask the OS for 
help with -- like filesystem operations) at the point in time when it 
crashed.

Let me echo something that's already been expressed: Since rdiff-backup 
is written in Python, it itself is not going to segfault. What you're 
seeing is some lower-level component going boom -- and strace should 
show you what's going on.

If it isn't enlightening at first, consider telling it to follow forks 
and setting a decently large string buffer length. Tell it to output to 
file rather than screen -- the output is *long*, and just writing it all 
to screen will slow things down substantially. If you can't read the 
output, consider posting *the bits at the end, before the segfault* to 
the list or putting the full trace up, compressed with bzip2, on a 
website and posting the URL.