Re: NULL strings cause "segmenation fault"

Mark Eichin (eichin@cygnus.com)
24 Sep 1996 04:40:19 -0400

> It seems that if s or t are NULL pointers (as they are when first
> allocated) then I get the fault. According to the MAN page on strcmp, if
> s or t are NULL then they are treated as if they point to NULL-terminated
> string. So I shouldn't have to check for this in my program.

1) char *s; doesn't *initialize* s to anything -- it just makes it use
some space... which may have a random value in it. That alone would
crash strcmp.

2) I've never seen a strcmp which was actually documented as treeting
NULL pointers specially. In particular, no linux version is
documented this way.

> I tried updating the compiler from GCC 2.6.3 to 2.7.2 - no help. I tried

Time to update your C programming textbook :-)