Here is a simple example showing the use of strtok. 

     #include <string.h>
     #include <stddef.h>
     
     ...
     
     const char string[] = "words separated by spaces -- and, punctuation!";
     const char delimiters[] = " .,;:!-";
     char *token, *cp;
     
     ...
     
     cp = strdupa (string);                /* Make writable copy.  */
     token = strtok (cp, delimiters);      /* token => "words" */
     token = strtok (NULL, delimiters);    /* token => "separated" */
     token = strtok (NULL, delimiters);    /* token => "by" */
     token = strtok (NULL, delimiters);    /* token => "spaces" */
     token = strtok (NULL, delimiters);    /* token => "and" */
     token = strtok (NULL, delimiters);    /* token => "punctuation" */
     token = strtok (NULL, delimiters);    /* token => NULL */