Thread: Best way to find, extract, replace, etc in char strings?

I could never figure out an easy way to handle strings in C. I need to find and extract part of a string up to the last occurrence of a particular character, and probably find/replace. I assume everything I need is in string.h, but I'm not having an easy time finding examples of specific tasks. For example. strrchar() returns a pointer. How am I supposed to use that pointer to extract everything up to that character? strncpy() expects to be told the number of chars to extract, not a pointer to the last one.

Also, is there a simple way to trim BS characters from the start and end of a strings? VB6 had a Trim() function that filtered out whitespace and other special chars(\t,\n, etc) from the beginning and end of a string.

I'm currently working with my char strings declared "char stringname[maxlength];" I'm curious as to the difference between this and cString/LPSTR. I don't think I've ever seen a cString used in an example without having to malloc() the damn thing. I don't want to do that, since you always have to free the memory later. Or is cString like the MFC solution to Char*? I want to stay away from MFC.

If you have
char array[ ] = "hello.world";

And
char *p = strchr( array, '.' );

Then you can do
ptrdiff_t n = p - array;
n in this example would be 5.

You could then use that as a parameter to say strncpy.

uhhh "ptrdiff_t undeclared"

#include <stddef.h>

Define does not work.

strncpy(INIFile,INIFile,chrloc);
This line is also suspect.
Not only would it be undefined, but you're copying the same data into the buffer that's already in it.

Oh, parsing simple input is not difficult at all. But it's more difficult in C, than higher-level languages.

Originally Posted by Kudose

With a padded keyboard and desk.

That's when you move on to working with floats...

QuantumPete