strtok_r

/* 
 * public domain strtok_r() by Charlie Gordon
 *
 *   from comp.lang.c  9/14/2007
 *
 *      http://groups.google.com/group/comp.lang.c/msg/2ab1ecbb86646684
 *
 *     (Declaration that it's public domain):
 *      http://groups.google.com/group/comp.lang.c/msg/7c7b39328fefab9c
 */
 
char* strtok_r(
    char *str, 
    const char *delim, 
    char **nextp)
{
    char *ret;
 
    if (str == NULL)
    {
        str = *nextp;
    }
 
    str += strspn(str, delim);
 
    if (*str == '\0')
    {
        return NULL;
    }
 
    ret = str;
 
    str += strcspn(str, delim);
 
    if (*str)
    {
        *str++ = '\0';
    }
 
    *nextp = str;
 
    return ret;
}