1 .\" Copyright (c) 1983, 1991 The Regents of the University of California.
2 .\" All rights reserved.
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5 .\" modification, are permitted provided that the following conditions
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14 .\" This product includes software developed by the University of
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20 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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28 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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32 .\" @(#)readlink.2 6.8 (Berkeley) 3/10/91
34 .\" Modified Sat Jul 24 00:10:21 1993 by Rik Faith <faith@cs.unc.edu>
35 .\" Modified Tue Jul 9 23:55:17 1996 by aeb
36 .\" Modified Fri Jan 24 00:26:00 1997 by aeb
38 .\" Japanese Version Copyright (c) 1997 HANATAKA Shinya
39 .\" all rights reserved.
40 .\" Translated 1997-12-12, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
41 .\" Updated 2005-02-10, Yuichi SATO <ysato444@yahoo.co.jp>
42 .\" Updated 2006-07-19, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>, LDP v2.36
43 .\" Updated 2008-08-06, Akihiro MOTOKI, LDP v3.05
45 .\"WORD: symbolic link シンボリック・リンク
48 .\"WORD: global variable グローバル変数
49 .\"WORD: directory ディレクトリ
51 .TH READLINK 2 2010-09-20 "Linux" "Linux Programmer's Manual"
54 .\"O readlink \- read value of a symbolic link
55 readlink \- シンボリック・リンクの値を読む
58 .B #include <unistd.h>
60 .BI "ssize_t readlink(const char *" path ", char *" buf ", size_t " bufsiz );
63 .\"O Feature Test Macro Requirements for glibc (see
64 .\"O .BR feature_test_macros (7)):
66 .RB ( feature_test_macros (7)
73 _BSD_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
74 _XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED || _POSIX_C_SOURCE\ >=\ 200112L
80 .\"O places the contents of the symbolic link
97 .\"O does not append a null byte to
103 .\"O It will truncate the contents (to a length of
105 .\"O characters), in case the buffer is too small to hold all of the contents.
106 その内容全てを格納するのにバッファーが小さ過ぎる場合は、
109 .\"O .SH "RETURN VALUE"
113 .\"O returns the number of bytes placed in
115 .\"O On error, \-1 is returned and
117 .\"O is set to indicate the error.
130 .\"O Search permission is denied for a component of the path prefix.
132 .\"O .BR path_resolution (7).)
133 パスのディレクトリ部分に検索許可が与えられていない
134 .RB ( path_resolution (7)
139 .\"O extends outside the process's allocated address space.
141 がプロセスに割り当てられたアドレス空間の外を指している。
145 .\"O is not positive.
148 .\" At the glibc level, bufsiz is unsigned, so this error can only occur
149 .\" if bufsiz==0. However, the in the kernel syscall, bufsiz is signed,
150 .\" and this error can also occur if bufsiz < 0.
151 .\" See: http://thread.gmane.org/gmane.linux.man/380
152 .\" Subject: [patch 0/3] [RFC] kernel/glibc mismatch of "readlink" syscall?
155 .\"O The named file is not a symbolic link.
156 指定したファイルがシンボリック・リンクでない。
159 .\"O An I/O error occurred while reading from the file system.
160 ファイル・システムの読み込み中に I/O エラーが起こった。
163 .\"O Too many symbolic links were encountered in translating the pathname.
167 .\"O A pathname, or a component of a pathname, was too long.
171 .\"O The named file does not exist.
175 .\"O Insufficient kernel memory was available.
179 .\"O A component of the path prefix is not a directory.
180 パスのディレクトリ部分がディレクトリでない。
181 .\"O .SH "CONFORMING TO"
184 .\"O .RB ( readlink ()
185 .\"O first appeared in 4.2BSD),
189 は 4.2BSD で初めて登場した), POSIX.1-2001.
192 .\"O In versions of glibc up to and including glibc 2.4, the return type of
196 .\"O Nowadays, the return type is declared as
198 .\"O as (newly) required in POSIX.1-2001.
199 バージョン 2.4 以前の glibc (バージョン 2.4 を含む) では、
207 は POSIX.1-2001 で (新たに) 必須となった)。
214 .BR path_resolution (7),