Split string by a substring

Question

I have following string:

char str[] = \"A/USING=B)\";

I want to split to get separate A and B values with /

Answer 1

As others have pointed out, you can use strstr from to find the delimiter in your string. Then either copy the substrings or modify the input string to split it.

Here's an implementation that returns the second part of a split string. If the string can't be split, it returns NULL and the original string is unchanged. If you need to split the string into more substrings, you can call the function on the tail repeatedly. The first part will be the input string, possibly shortened.

#include 
#include 
#include 

char *split(char *str, const char *delim)
{
    char *p = strstr(str, delim);

    if (p == NULL) return NULL;     // delimiter not found

    *p = '\0';                      // terminate string after head
    return p + strlen(delim);       // return tail substring
}

int main(void)
{
    char str[] = "A/USING=B";
    char *tail;

    tail = split(str, "/USING=");

    if (tail) {
        printf("head: '%s'\n", str);
        printf("tail: '%s'\n", tail);
    }

    return 0;
}