osx man page for strspn

STRSPN(3)						   BSD Library Functions Manual 						 STRSPN(3)

NAME
     strspn -- span a string

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <string.h>

     size_t
     strspn(const char *s1, const char *s2);

DESCRIPTION
     The strspn() function spans the initial part of the null-terminated string s1, as long as the characters from s1 occur in the null-terminated
     string s2.  In other words, it computes the string array index in s1 of the first character of s1 which is not in s2, else the index of the
     first null character.

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

SEE ALSO
     memchr(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strstr(3), strtok(3), wcsspn(3)

STANDARDS
     The strspn() function conforms to ISO/IEC 9899:1990 (``ISO C90'').

BSD
								   June 4, 1993 							       BSD