strspn(3) - BetterMan

strspn(3)

get length of a prefix substring

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Synopsis

#include <string.h>
size_t strspn(const char *
s
, const char *
accept
);
size_t strcspn(const char *
s
, const char *
reject
);

—

NAME

strspn, strcspn - get length of a prefix substring

Standard C library (libc, -lc)

bash

#include <string.h>

bash

size_t strspn(const char *\ns\n, const char *\naccept\n);\n
\nsize_t strcspn(const char *\ns\n, const char *\nreject\n);

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.

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.

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
strspn (), strcspn ()	Thread safety	MT-Safe

C11, POSIX.1-2008.

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