102 lines
2.8 KiB
Groff
102 lines
2.8 KiB
Groff
.\" $OpenBSD: memchr.3,v 1.14 2024/12/11 23:28:20 jsg Exp $
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.\"
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.\" Copyright (c) 1990, 1991 The Regents of the University of California.
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.\" All rights reserved.
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.\"
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.\" This code is derived from software contributed to Berkeley by
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.\" Chris Torek and the American National Standards Committee X3,
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.\" on Information Processing Systems.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.Dd $Mdocdate: December 11 2024 $
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.Dt MEMCHR 3
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.Os
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.Sh NAME
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.Nm memchr ,
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.Nm memrchr
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.Nd locate byte in byte string
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.Sh SYNOPSIS
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.In string.h
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.Ft void *
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.Fn memchr "const void *b" "int c" "size_t len"
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.Ft void *
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.Fn memrchr "const void *b" "int c" "size_t len"
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.Sh DESCRIPTION
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The
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.Fn memchr
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function locates the first occurrence of
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.Fa c
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(converted to an
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.Vt unsigned char )
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in string
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.Fa b .
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.Pp
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The
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.Fn memrchr
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function behaves like
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.Fn memchr ,
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except that it locates the last occurrence of
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.Fa c
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in string
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.Fa b .
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.Sh RETURN VALUES
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The
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.Fn memchr
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and
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.Fn memrchr
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functions return a pointer to the byte located, or
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.Dv NULL
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if no such byte exists within
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.Fa len
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bytes.
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.Sh SEE ALSO
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.Xr strchr 3 ,
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.Xr strcspn 3 ,
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.Xr strpbrk 3 ,
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.Xr strrchr 3 ,
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.Xr strsep 3 ,
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.Xr strspn 3 ,
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.Xr strstr 3 ,
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.Xr strtok 3 ,
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.Xr wmemchr 3
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.Sh STANDARDS
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The
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.Fn memchr
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function conforms to
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.St -ansiC .
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.Pp
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The
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.Fn memrchr
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function is an
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.Ox
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extension.
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.Sh HISTORY
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The
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.Fn memchr
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function first appeared in
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.At V
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and was reimplemented for
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.Bx 4.3 .
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