Re: strtok causes Segmentation fault

bofh1234@xxxxxxxxxxx wrote:
I understand strtok seg faulting if the FIRST call is with NULL, but
in my case the first call is not NULL. It is
tokenptr = strtok(list, ";"); //this line causes the seg fault WHY?
list is a varible passed to the function.
You are passing a string literal as the list parameter, which you then
send to strtok(). This causes undefined behavior.

So?? I tried strtok(*list, ";"); and it still seg faults. According
to my old C book strtok is supposed to take a string for the first
argument. I even tried changing createvarible to:
int createvarible(const int sock, char *varname, char *vartype, char
*initialvalue, char accesslist[64])
and I still get a seg fault. How can I get this thing to work.

Think:

char *strtok(char *s1, const char *s2);

The string [s1] passed to strtok() must be mutable, because it is a destructive function. Your appear to be passing the function a static buffer or literal string.

Slow down a bit and re-read all the comments posted so far.

Consider:

[...]
char *fnord = "Fnord Motor Company";
fnord[0] = 'f'; /* Undefined behaviour */
[...]

Can you legally modify fnord, even with a direct assignment? If not, what about a library function like strtok()?
.

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