bsd man page for strcspn

STRCSPN(3)						     Library Functions Manual							STRCSPN(3)

NAME
       strcspn - span the complement of a string

SYNOPSIS
       #include <string.h>

       size_t
       strcspn(s, charset)
       char *s;
       char *charset;

DESCRIPTION
       The  strcspn()  function  spans	the  initial  part of the null-terminated string s as long as the characters from s do not occur in string
       charset (it spans the complement of charset ) .

RETURN VALUES
       The strcspn() function returns the number of characters spanned.

SEE ALSO
       index(3), memchr(3), rindex(3), strchr(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strstr(3), strtok(3)

STANDARDS
       The strcspn() function conforms to ANSI C X3.159-1989 (``ANSI C'').

4.4 Berkeley Distribution					 January 12, 1996							STRCSPN(3)