strspn(3)

NAME
strspn, strcspn - get length of a prefix substring

LIBRARY
Standard C library (libc, -lc)

SYNOPSIS
#include <string.h>

size_t strspn(const char *s, const char *accept);
size_t strcspn(const char *s, const char *reject);

DESCRIPTION

strspn()
    The strspn() function calculates the length (in bytes) of the initial segment of s which consists entirely of bytes in accept.

strcspn()
    The strcspn() function calculates the length of the initial segment of s which consists entirely of bytes not in reject.

    It is equivalent to

        (strpbrk(s, reject) ?: strnul(s)) - s

RETURN VALUE
The strspn() function returns the number of bytes in the initial segment of s which consist only of bytes from accept.

The strcspn() function returns the number of bytes in the initial segment of s which are not in the string reject.

ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value
 | Thread safety | MT-Safe

STANDARDS
C11, POSIX.1-2008.

HISTORY
POSIX.1-2001, C89, SVr4, 4.3BSD.

SEE ALSO
memchr(3), strchr(3), string(3), strpbrk(3), strsep(3), strstr(3), strtok(3), wcscspn(3), wcsspn(3)