strspn(3) Library Functions Manual 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
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 seg-
ment 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), str-
tok(3), wcscspn(3), wcsspn(3)
Linux man-pages 6.9.1 2024-05-02 strspn(3)
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