[linuxjm/LDP_man-pages.git] / release / man2 / dup.2

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.\" This manpage is Copyright (C) 1992 Drew Eckhardt;
.\" and Copyright (C) 1993 Michael Haardt, Ian Jackson.
.\" and Copyright (C) 2005, 2008 Michael Kerrisk <mtk.manpages@gmail.com>
.\"
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.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
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.\" 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.\" manual page may be incorrect or out-of-date.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
.\" have taken the same level of care in the production of this manual,
.\" which is licensed free of charge, as they might when working
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.\" 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
.\" 2009-01-12, mtk, reordered text in DESCRIPTION and added some
.\"     details for dup2().
.\" 2008-10-09, mtk: add description of dup3()
.\"
.\" 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
.\" Updated 2008-02-10, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>, LDP v2.77
.\" Updated 2008-11-09, Akihiro MOTOKI, LDP v3.13
.\"
.TH DUP 2 2010-09-10 "Linux" "Linux Programmer's Manual"
.SH ̾Á°
dup, dup2, dup3 \- ¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿¤òÊ£À½¤¹¤ë
.SH ½ñ¼°
.nf
.B #include <unistd.h>
.sp
.BI "int dup(int " oldfd );
.BI "int dup2(int " oldfd ", int " newfd );
.sp
.BR "#define _GNU_SOURCE" "             /* feature_test_macros(7) »²¾È */"
.B #include <unistd.h>
.sp
.BI "int dup3(int " oldfd ", int " newfd ", int " flags );
.fi
.SH ÀâÌÀ
¤³¤ì¤é¤Î¥·¥¹¥Æ¥à¥³¡¼¥ë¤Ï¡¢¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿
.I oldfd
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.BR dup ()
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¿·¤·¤¤¥Ç¥£¥¹¥¯¥ê¥×¥¿¤È¤·¤Æ»ÈÍѤ¹¤ë¡£

.BR dup2 ()
¤Ï
.I newfd
¤ò
.I oldfd
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ɬÍפǤ¢¤ì¤ÐºÇ½é¤Ë
.I newfd
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.IP * 3
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.I newfd
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.IP *
.I oldfd
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.I newfd
¤¬
.I oldfd
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.BR dup2 ()
¤Ï²¿¤â¤»¤º¡¢
.I newfd
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.PP
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2¤Ä¤Î¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿¤ÏƱ¤¸¥Õ¥¡¥¤¥ëµ­½Ò (description)
.RB ( open (2)
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.BR lseek (2)
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2¤Ä¤Î¥Ç¥£¥¹¥¯¥ê¥×¥¿¤Ï¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿¡¦¥Õ¥é¥° (close-on-exec flag)
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close-on-exec flag
.RB ( fcntl (2)
»²¾È) ¤Ï off ¤È¤Ê¤ë¡£

.BR dup3 ()
¤Ï
.BR dup2 ()
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.IP * 3
¸Æ¤Ó½Ð¤·¸µ¤¬¡¢¿·¤·¤¤¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿¤ËÂФ·¤Æ
close-on-exec ¥Õ¥é¥°¤ò¶¯À©Åª¤ËÀßÄꤹ¤ë¤³¤È¤¬¤Ç¤­¤ë¡£
¤³¤ì¤ò¹Ô¤¦¤Ë¤Ï¡¢
.I flags
¤Ë
.B O_CLOEXEC
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.BR open (2)
¤Î
.B O_CLOEXEC
¥Õ¥é¥°¤ÎÀâÌÀ¤ò»²¾È¤Î¤³¤È¡£
.IP *
.\" FIXME . To confirm with Al Viro that this was intended, and its rationale
.I oldfd
¤¬
.I newfd
¤ÈƱ¤¸¾ì¹ç¡¢
.BR dup3 ()
¤Ï
.B EINVAL
¥¨¥é¡¼¤Ç¼ºÇÔ¤¹¤ë¡£
.SH ÊÖ¤êÃÍ
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¥¨¥é¡¼¤Î¾ì¹ç¡¢\-1 ¤òÊÖ¤·¡¢
.I errno
¤òŬÀÚ¤ËÀßÄꤹ¤ë¡£
.SH ¥¨¥é¡¼
.TP
.B EBADF
.I oldfd
¤¬¥ª¡¼¥×¥ó¤µ¤ì¤¿¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿¤Ç¤Ê¤¤¤«¡¢
.I newfd
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.TP
.B EBUSY
(Linux ¤Î¤ß)
.BR open (2)
¤ä
.BR dup ()
¤È¤Î¶¥¹ç¾õÂ֤ξì¹ç¤Ë¡¢
.BR dup2 ()
¤ä
.BR dup3 ()
¤Ï¤³¤Î¥¨¥é¡¼¤òÊÖ¤¹¤«¤â¤·¤ì¤Ê¤¤¡£
.TP
.B EINTR
.BR dup2 ()
¤ä
.BR dup3 ()
¤Î¸Æ¤Ó½Ð¤·¤¬¥·¥°¥Ê¥ë¤Ë¤è¤ê³ä¤ê¹þ¤Þ¤ì¤¿¡£
.BR signal (7)
»²¾È¡£
.TP
.B EINVAL
.RB ( dup3 ())
.I flags
¤Ë̵¸ú¤ÊÃͤ¬Æþ¤Ã¤Æ¤¤¤ë¡£
.\" FIXME . To confirm with Al Viro that this was intended, and its rationale
¤â¤·¤¯¤Ï¡¢
.I oldfd
¤¬
.I newfd
¤ÈƱ¤¸¤Ç¤¢¤Ã¤¿¡£
.TP
.B EMFILE
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¤ò³«¤¤¤Æ¤¤¤Æ¡¢¤µ¤é¤Ë¿·¤·¤¤¤â¤Î¤ò³«¤³¤¦¤È¤·¤¿¡£
.SH ¥Ð¡¼¥¸¥ç¥ó
.BR dup3 ()
¤Ï¥Ð¡¼¥¸¥ç¥ó 2.6.27 ¤Ç Linux ¤ËÄɲ䵤줿¡£
glibc ¤Ë¤è¤ë¥µ¥Ý¡¼¥È¤Ï¥Ð¡¼¥¸¥ç¥ó 2.9 °Ê¹ß¤ÇÍøÍѤǤ­¤ë¡£
.SH ½àµò
.BR dup (),
.BR dup2 ():
SVr4, 4.3BSD, POSIX.1-2001.

.BR dup3 ()
¤Ï Linux ¸ÇÍ­¤Ç¤¢¤ë¡£
.\" SVr4 ¤Ë¤Ï¾¤Ë EINTR, ENOLINK ¥¨¥é¡¼¾õÂ֤ε­½Ò¤¬¤¢¤ë¡£
.\" POSIX.1 ¤Ë¤Ï¾¤Ë EINTR ¤¬¤¢¤ë¡£
.\" EBUSY ¤¬ÊÖ¤µ¤ì¤ë¤Î¤Ï Linux Æȼ«¤Î¤â¤Î¤Ç¤¢¤ë¡£
.SH Ãí°Õ
.I newfd
¤¬ÈϰϤòĶ¤¨¤¿»þ¤ËÊÖ¤µ¤ì¤ë¥¨¥é¡¼¤Ï¡¢
.BR dup2 ()
¤È
.BR fcntl( "..., " F_DUPFD ", ..." )
¤Ç¤Ï°Û¤Ã¤Æ¤¤¤ë¡£
.BR dup2 ()
¤¬
.B F_DUPFD
¤ÈƱ¤¸¤è¤¦¤Ë
.B EINVAL
¤òÊÖ¤¹¥·¥¹¥Æ¥à¤â¤¢¤ë¡£

.I newfd
¤¬¥ª¡¼¥×¥ó¤µ¤ì¤Æ¤¤¤ë¤È¡¢
.BR close (2)
¤·¤¿»þ¤ËÊó¹ð¤µ¤ì¤ë¤Ï¤º¤Î¥¨¥é¡¼¤¬¼º¤ï¤ì¤Æ¤·¤Þ¤¦¡£
.BR dup2 ()
¤ä
.BR dup3 ()
¤ò»È¤¦Á°¤ËÀ褺
.I newfd
¤ò¥¯¥í¡¼¥º¤¹¤ë¤è¤¦¤Ë¤·¤¿Êý¤¬¤¤¤¤¤À¤í¤¦¡£
.SH ´ØÏ¢¹àÌÜ
.BR close (2),
.BR fcntl (2),
.BR open (2)