/* ------- file toksplit.c ----------*/
#include "toksplit.h"

/* copy over the next token from an input string, after
   skipping leading blanks (or other whitespace?).  The
   token is terminated by the first appearance of tokchar,
   or by the end of the source string.

   The caller must supply sufficient space in token to
   receive any token,  Otherwise tokens will be truncated.

   Returns: a pointer past the terminating tokchar.

   This will happily return an infinity of empty tokens if
   called with src pointing to the end of a string.  Tokens
   will never include a copy of tokchar.

   A better name would be "strtkn", except that is reserved
   for the system namespace.  Change to that at your risk.

   released to Public Domain, by C.B. Falconer.
   Published 2006-02-20.  Attribution appreciated.
   Revised   2006-06-13
*/

const char *toksplit(const char *src,      /* Source of tokens */
                     char tokchar,    /* token delimiting char */
                     char *token,  /* receiver of parsed token */
                     size_t lgh)   /* length token can receive */
                                   /* not including final '\0' */
{
   if (src) {
      while (' ' == *src) src++;

      while (*src && (tokchar != *src)) {
         if (lgh) {
            *token++ = *src;
            --lgh;
         }
         src++;
      }
      if (*src && (tokchar == *src)) src++;
   }
   *token = '\0';
   return src;

#define ABRsize 6 /* length of acceptable token abbreviations */

/* ---------------- */

static void showtoken(int i, char *tok)
{
   putchar(i + '1'); putchar(':');
   puts(tok);

int main(void)
{
   char teststring[] = "This is a test, ,,   abbrev, more";

   const char *t, *s = teststring;
   int         i;
   char        token[ABRsize + 1];

   puts(teststring);
   t = s;
   for (i = 0; i < 4; i++) {
      t = toksplit(t, ',', token, ABRsize);
      showtoken(i, token);
   }

   puts("\nHow to detect 'no more tokens' while truncating");
   t = s; i = 0;
   while (*t) {
      t = toksplit(t, ',', token, 3);
      showtoken(i, token);
      i++;
   }

   puts("\nUsing blanks as token delimiters");
   t = s; i = 0;
   while (*t) {
      t = toksplit(t, ' ', token, ABRsize);
      showtoken(i, token);
      i++;
   }
   return 0;

/* ------- file toksplit.h ----------*/
#ifndef H_toksplit_h
#  define H_toksplit_h

#  ifdef __cplusplus
      extern "C" {
#  endif

#include <stddef.h>

/* copy over the next token from an input string, after
   skipping leading blanks (or other whitespace?).  The
   token is terminated by the first appearance of tokchar,
   or by the end of the source string.

   The caller must supply sufficient space in token to
   receive any token,  Otherwise tokens will be truncated.

   Returns: a pointer past the terminating tokchar.

   This will happily return an infinity of empty tokens if
   called with src pointing to the end of a string.  Tokens
   will never include a copy of tokchar.

   released to Public Domain, by C.B. Falconer.
   Published 2006-02-20.  Attribution appreciated.
*/

const char *toksplit(const char *src,      /* Source of tokens */
                     char tokchar,    /* token delimiting char */
                     char *token,  /* receiver of parsed token */
                     size_t lgh);  /* length token can receive */
                                   /* not including final '\0' */

#  ifdef __cplusplus
      }
#  endif
#endif
/* ------- end file toksplit.h ----------*/

--
 <http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt>
 <http://www.securityfocus.com/columnists/423>
 <http://www.aaxnet.com/editor/edit043.html>
 <http://kadaitcha.cx/vista/dogsbreakfast/index.html>
                        cbfalconer at maineline dot net