strspn(3) get length of a prefix substring

Other Alias

strcspn

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).
InterfaceAttributeValue
strspn(), strcspn() Thread safetyMT-Safe

CONFORMING TO

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

COLOPHON

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