strcspn

   NAME
    strcspn - scan a string until a character is found that matches
          any character in a second string.

   SYNOPSIS
    int len = strcspn(s, toks)
    const char *s;
    const char *toks;

   FUNCTION
    The string s is scanned until a character is found that matches any
    character in the string toks.  The number of characters skipped is
    returned.  If no character in s matches any character in toks then
    the length of the string s is returned.

    This function is normally used to search for whitespace within a
    string.  Note that in many cases strpbrk() is more useful than
    strcspn().

   EXAMPLE
    #include <stdio.h>
    #include <string.h>
    #include <assert.h>

    main()
    {
        int len;

        len = strcspn("hello this is a test", " tabcd");
        assert(len == 5);               /*  stopped at the first space  */

        len = strcspn("hello this is a test", " abl");
        assert(len == 2);               /*  stopped at the first 'l'    */

        len = strcspn("hello", "abcd");
        assert(len == 5);               /*  stopped at end of string 1  */

        return(0);
    }

   INPUTS
    char *s;    pointer to string to scan
    char *toks; pointer to string containing characters to compare against

   RESULTS
    int len;    # of characters skipped in s before a match was found

   SEE ALSO
    strpbrk, strspn