comparing char values

[FoodDude]

I'm a bit stumpted on this one. First off, I'm writing this to be ported to C, so I'm using char and NOT using string stuff.

Here is the problem. The code compiles but doesn't run correctly. At the if pch = line, I see that both pch and stringtofind are defined as char * fields. However, when both contain the phrase "get" the code doesn't fall into the if code but jumps down to the else if line.

Why, if two fields are defined as char * and both have the same value ("get") , aren't they evaulated as the same? My only thought it that it has something to do with pointers.

const char * get_domain(char * cBuffer, char * strtofind)
{
	//pull the URL from the header packet
	//where header is build like
	//...get /stuff/index.html ...

	int flag = 0;
	char * pch;
	//break packet out by spaces as a delimiter
	pch = strtok (cBuffer," ");
	while (pch != NULL)
	{
		//review each bucket and look for the phrase "get"
		if (pch == strtofind)
		{
			//indicates get is found
			//flag to grab the next bucket of data which will contain the page location
			//which could be something like /stuff/index.html 
			flag = 1;
		}
		else if (flag == 1)
		{
			return pch;
		}
		pch = strtok (NULL, " ");
	}
	return "[NONE]";
}

[ZuK]

Your code is comparing pointers. Use strcmp() instead.
Kurt

[FoodDude]

Thanks.

[FoodDude]

One more interesteing point, if I call the function again, it doesn't perform properly. I have just read the MSDN info that:

"Each of these functions uses a static variable for parsing the string into tokens. If multiple or simultaneous calls are made to the same function, a high potential for data corruption and inaccurate results exists. Therefore, do not attempt to call the same function simultaneously for different strings and be aware of calling one of these function from within a loop where another routine may be called that uses the same function. However, calling this function simultaneously from multiple threads does not have undesirable effects."

But if I can't call the function more than once within the same thread??? I think I've read about this problem, here.

[edit] Ok, I found that subsequent calls would just have NULL sent as the field pointer. Anything else I should know?

[Ancient Dragon]

you can call strtok() as many times as you want in the same thread. That warning means you can only use strtok() on only one string at a time -- calls can't be nested. This example is WRONG

char *p1 = strtok("once upon a time", " ");
while(p1 != NULL)
{
   char* p2 = strtok("there lived three little pigs"," ");
   // blabla
   p1 = strtok(NULL," "); // p1 will now point somewhere inside the string passed to p2
}

[dwks]

Okay, so what is right?

[edit]See the FAQ.[/edit]

[Ancient Dragon]

Okay, so what is right?

see the op's original post on this thread (and the FAQ you cited) -- it's correct use of strtok().