STRSPN(3) BSD Programmer's Manual STRSPN(3)
strspn - span a string
#include <string.h> size_t strspn(const char *s, const char *charset);
The strspn() function spans the initial part of the NUL-terminated string s as long as the characters from s occur in string charset.
The strspn() function returns the number of characters spanned.
The following call to strspn() will return 3, since the first three char- acters of string s are part of string charset: char *s = "foobar"; char *charset = "of"; size_t span; span = strspn(s, charset);
memchr(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strstr(3), strtok(3)
The strspn() function conforms to ANSI X3.159-1989 ("ANSI C89"). MirBSD #10-current June 29, 1991 1