NAME

       strspn, strcspn - get length of a prefix substring

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 │
       └───────────────────────────────────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO

       POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.

SEE ALSO

       index(3),  memchr(3),  rindex(3),  strchr(3), string(3), strpbrk(3), strsep(3), strstr(3),
       strtok(3), wcscspn(3), wcsspn(3)

COLOPHON

       This page is part of release 5.13 of the Linux man-pages project.  A  description  of  the
       project,  information  about  reporting  bugs, and the latest version of this page, can be
       found at https://www.kernel.org/doc/man-pages/.

                                            2021-03-22                                  STRSPN(3)