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

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

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

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   │
       ├───────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │strspn(), strcspn()                                            │ 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)