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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 5.05 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/.
2015-08-08 STRSPN(3)