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.\" Hey Emacs! This file is -*- nroff -*- source.
.\"
.\" This manpage is Copyright (C) 1992 Drew Eckhardt;
.\" 1993 Michael Haardt, Ian Jackson.
.\"
.\" 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.
.\"
.\" 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.\" manual page may be incorrect or out-of-date.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
.\" have taken the same level of care in the production of this manual,
.\" which is licensed free of charge, as they might when working
.\" professionally.
.\"
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and authors of this work.
.\"
.\" Modified 1993-07-21, Rik Faith <faith@cs.unc.edu>
.\" Modified 1994-08-21, Michael Chastain <mec@shell.portal.com>:
.\" Fixed typoes.
.\" Modified 1997-01-31, Eric S. Raymond <esr@thyrsus.com>
.\" Modified 2002-09-28, aeb
.\"
.\" Japanese Version Copyright (c) 1996 Takeshi Ueno
.\" all rights reserved.
.\" Translated 1996-07-03, Takeshi Ueno <tueno@vio.co.jp>
.\" Modified 1997-12-14, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Modified 2003-01-16, Akihiro Motoki <amotoki@dd.iij4u.or.jp>
.\" Updated & Modified 2004-05-19, Yuichi SATO <ysato444@yahoo.co.jp>
.\" Updated & Modified 2005-09-07 Akihiro MOTOKI
.\"
.TH DUP 2 1994-08-21 "Linux 1.1.46" "Linux Programmer's Manual"
.SH ̾
dup, dup2 \- ե롦ǥץʣ
.SH
.nf
.B #include <unistd.h>
.sp
.BI "int dup(int " oldfd );
.BI "int dup2(int " oldfd ", int " newfd );
.fi
.SH
.BR dup ()
.BR dup2 ()
ϡե롦ǥץ
.I oldfd
ʣ롣
\fBdup\fR() ޤ \fBdup2\fR() ֤ˤϡ
Ťե롦ǥץȿե롦ǥץ
ߤ˲ĴʤΤȤƻȤȤǤ롣
2ĤΥե롦ǥץƱե뵭 (description)
.RB ( open (2)
) ȤƤꡢäƥե륪եåȤե֥ե饰
ͭ롣㤨СΥǥץФ
.BR lseek (2)
Ȥäƥե륪եåȤѹ硢⤦Υǥץ
եåȤѲ롣
2ĤΥǥץϥե롦ǥץե饰 (close-on-exec flag)
ͭʤʣ줿ǥץ
close-on-exec flag
.RB ( fcntl (2)
) off Ȥʤ롣
.BR dup ()
ϻѤƤʤǾͤΥǥץǥץ
ȤƻѤ롣
.BR dup2 ()
.I oldfd
ʣȤ
.I newfd
롣ɬפʤкǽ
.I newfd
(close) 롣
.SH ֤
.BR dup ()
.BR dup2 ()
Ͽǥץ֤顼ξ \-1 ֤
(λ
.I errno
Ŭڤͤꤵ롣)
.SH 顼
.TP
.B EBADF
.I oldfd
ץ줿ե롦ǥץǤʤ
.I newfd
ե롦ǥץȤƵϰϤ鳰Ƥ롣
.TP
.B EBUSY
(Linux Τ)
.BR open ()
.BR dup ()
Ȥζ֤ξˡ
.BR dup2 ()
ϤΥ顼֤⤷ʤ
.TP
.B EINTR
.BR dup2 ()
θƤӽФʥˤäƳޤ줿 (interrupt)
.TP
.B EMFILE
ץǤ˥ץǤޤǥե롦ǥץ
Ƥơ˿ΤȤ
.SH ٹ
.I newfd
ϰϤĶ֤륨顼ϡ
.BR dup2 ()
.BR fcntl( "..., " F_DUPFD ", ..." )
ǤϰۤäƤ롣
.BR dup2 ()
.B F_DUPFD
Ʊ褦
.B EINVAL
֤ƥ⤢롣
.I newfd
ץƤȡ
.BR close ()
𤵤ϤΥ顼Ƥޤ
.BR dup2 ()
Ȥ褺
.I newfd
褦ˤ
.SH
SVr4, 4.3BSD, POSIX.1-2001.
.\" SVr4 ˤ¾ EINTR, ENOLINK 顼֤εҤ롣
.\" POSIX.1 ˤ¾ EINTR 롣
.\" EBUSY ֤Τ Linux ȼΤΤǤ롣
.SH Ϣ
.BR close (2),
.BR fcntl (2),
.BR open (2)
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