39 lines
817 B
C
39 lines
817 B
C
/*
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* uses strpbrk and strspn to break string into tokens on
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* sequentially subsequent calls. returns NULL when no
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* non-separator characters remain.
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* `subsequent' calls are calls with first argument NULL.
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*/
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#define NULL (char*)0
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extern int strspn();
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extern char *strpbrk();
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char *
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strtok(string, sepset)
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char *string, *sepset;
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{
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register char *p, *q, *r;
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static char *savept;
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/*first or subsequent call*/
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p = (string == NULL)? savept: string;
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if(p == 0) /* return if no tokens remaining */
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return(NULL);
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q = p + strspn(p, sepset); /* skip leading separators */
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if(*q == '\0') /* return if no tokens remaining */
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return(NULL);
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if((r = strpbrk(q, sepset)) == NULL) /* move past token */
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savept = 0; /* indicate this is last token */
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else {
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*r = '\0';
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savept = ++r;
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}
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return(q);
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}
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