.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)

.\"

.\" %%%LICENSE_START(VERBATIM)

.\" Permission is granted to make and distribute verbatim copies of this

.\" manual provided the copyright notice and this permission notice are

.\" preserved on all copies.

.\"

.\" Permission is granted to copy and distribute modified versions of this

.\" manual under the conditions for verbatim copying, provided that the

.\" entire resulting derived work is distributed under the terms of a

.\" permission notice identical to this one.

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.\" Since the Linux kernel and libraries are constantly changing, this

.\" manual page may be incorrect or out-of-date.  The author(s) assume no

.\" responsibility for errors or omissions, or for damages resulting from

.\" the use of the information contained herein.  The author(s) may not

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.\"

.\" References consulted:

.\"     Linux libc source code

.\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)

.\"     386BSD man pages

.\" Modified Sat Jul 24 17:57:50 1993 by Rik Faith (faith@cs.unc.edu)

.TH STRSPN 3  2015-08-08 "" "Linux Programmer's Manual"

.SH NAME

strspn, strcspn \- get length of a prefix substring

.SH SYNOPSIS

.nf

.B #include <string.h>

.PP

.BI "size_t strspn(const char *" s ", const char *" accept );

.PP

.BI "size_t strcspn(const char *" s ", const char *" reject );

.fi

.SH DESCRIPTION

The

.BR strspn ()

function calculates the length (in bytes) of the initial

segment of

.I s

which consists entirely of bytes in

.IR accept .

.PP

The

.BR strcspn ()

function calculates the length of the initial

segment of

.I s

which consists entirely of bytes not in

.IR reject .

.SH RETURN VALUE

The

.BR strspn ()

function returns the number of bytes in

the initial segment of

.I s

which consist only of bytes

from

.IR accept .

.PP

The

.BR strcspn ()

function returns the number of bytes in

the initial segment of

.I s

which are not in the string

.IR reject .

.SH ATTRIBUTES

For an explanation of the terms used in this section, see

.BR attributes (7).

.TS

allbox;

lbw19 lb lb

l l l.

Interface	Attribute	Value

T{

.BR strspn (),

.BR strcspn ()

T}	Thread safety	MT-Safe

.TE

.SH CONFORMING TO

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

.SH SEE ALSO

.BR index (3),

.BR memchr (3),

.BR rindex (3),

.BR strchr (3),

.BR string (3),

.BR strpbrk (3),

.BR strsep (3),

.BR strstr (3),

.BR strtok (3),

.BR wcscspn (3),

.BR wcsspn (3)

.SH COLOPHON

This page is part of release 4.15 of the Linux

.I 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/.