1 .\" Hey Emacs! This file is -*- nroff -*- source.
3 .\" This manpage is Copyright (C) 2006, Michael Kerrisk
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9 .\" Permission is granted to copy and distribute modified versions of this
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14 .\" Since the Linux kernel and libraries are constantly changing, this
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19 .\" which is licensed free of charge, as they might when working
22 .\" Formatted or processed versions of this manual, if unaccompanied by
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25 .\" Japanese Version Copyright (c) 2006-2007 Yuichi SATO
26 .\" all rights reserved.
27 .\" Translated 2006-10-14 by Yuichi SATO <ysato444@yahoo.co.jp>, LDP v2.39
28 .\" Updated & Modified 2007-01-08 by Yuichi SATO, LDP v2.43
29 .\" Updated 2007-05-04, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
31 .TH FACCESSAT 2 2009-12-13 "Linux" "Linux Programmer's Manual"
34 .\"O faccessat \- check user's permissions of a file relative to a \
35 .\"O directory file descriptor
36 faccessat \- ¥Ç¥£¥ì¥¯¥È¥ê¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿¤«¤éÁêÂÐŪ¤Ê°ÌÃ֤ˤ¢¤ë
37 ¥Õ¥¡¥¤¥ë¤Î¥¢¥¯¥»¥¹¸¢¤ò¥Á¥§¥Ã¥¯¤¹¤ë
41 .\"O .B #include <fcntl.h> /* Definition of AT_* constants */
42 .B #include <fcntl.h> /* AT_* Äê¿ô¤ÎÄêµÁ */
43 .B #include <unistd.h>
45 .BI "int faccessat(int " dirfd ", const char *" pathname ", int " \
46 mode ", int " flags );
50 .\"O Feature Test Macro Requirements for glibc (see
51 .\"O .BR feature_test_macros (7)):
52 glibc ¸þ¤±¤Îµ¡Ç½¸¡ºº¥Þ¥¯¥í¤ÎÍ×·ï
53 .RB ( feature_test_macros (7)
62 .\"O Since glibc 2.10:
64 _XOPEN_SOURCE\ >=\ 700 || _POSIX_C_SOURCE\ >=\ 200809L
66 .\"O Before glibc 2.10:
76 .\"O system call operates in exactly the same way as
78 .\"O except for the differences described in this manual page.
80 ¥·¥¹¥Æ¥à¥³¡¼¥ë¤Ï¡¢¤³¤Î man ¥Ú¡¼¥¸¤ÇÀâÌÀ¤·¤Æ¤¤¤ë°ã¤¤¤¬¤¢¤ë°Ê³°¤Ï¡¢
82 ¤ÈÁ´¤¯Æ±¤¸¤è¤¦¤ËÆ°ºî¤¹¤ë¡£
84 .\"O If the pathname given in
86 .\"O is relative, then it is interpreted relative to the directory
87 .\"O referred to by the file descriptor
89 .\"O (rather than relative to the current working directory of
90 .\"O the calling process, as is done by
92 .\"O for a relative pathname).
94 ¤Ç»ØÄꤵ¤ì¤ë¥Ñ¥¹Ì¾¤¬ÁêÂХѥ¹¤Ç¤¢¤ë¾ì¹ç¡¢
95 ¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿
97 ¤Ç»²¾È¤µ¤ì¤ë¥Ç¥£¥ì¥¯¥È¥ê¤«¤é¤ÎÁêÂХѥ¹Ì¾¤È¤·¤Æ²ò¼á¤µ¤ì¤ë
99 ¤Ç¤Ï¡¢ÁêÂХѥ¹¤Ï¸Æ¤Ó½Ð¤·¸µ¥×¥í¥»¥¹¤Î¥«¥ì¥ó¥È¥ï¡¼¥¥ó¥°¥Ç¥£¥ì¥¯¥È¥ê¤«¤é¤Î
106 .\"O is the special value
110 .\"O is interpreted relative to the current working
111 .\"O directory of the calling process (like
112 .\"O .BR access (2)).
114 ¤¬ÁêÂХѥ¹¤Ç¤¢¤ê¡¢¤«¤Ä
122 ¤ÈƱ¤¸¤è¤¦¤Ë) ¸Æ¤Ó½Ð¤·¸µ¥×¥í¥»¥¹¤Î
123 ¥«¥ì¥ó¥È¥ï¡¼¥¥ó¥°¥Ç¥£¥ì¥¯¥È¥ê¤«¤é¤ÎÁêÂХѥ¹Ì¾¤È¤·¤Æ²ò¼á¤µ¤ì¤ë¡£
127 .\"O is absolute, then
131 ¤¬ÀäÂХѥ¹¤Ç¤¢¤ë¾ì¹ç¡¢
136 .\"O is constructed by ORing together zero or more of the following values:
138 ¤Ï°Ê²¼¤ÎÃͤò 0 ¸Ä°Ê¾å OR ¤·¤Æºî¤é¤ì¤ë¡£
141 .\"O Perform access checks using the effective user and group IDs.
143 .\"O .BR faccessat ()
144 .\"O uses the real IDs (like
145 .\"O .BR access (2)).
146 ¼Â¸ú (effective) ¥æ¡¼¥¶ ID ¤È¼Â¸ú¥°¥ë¡¼¥× ID ¤ò»È¤Ã¤Æ¡¢
147 ¥¢¥¯¥»¥¹¸¢¤Î¥Á¥§¥Ã¥¯¤ò¹Ô¤¦¡£
152 ¤ÈƱÍͤË) ¼Â ID ¤ò»È¤¦¡£
154 .B AT_SYMLINK_NOFOLLOW
157 .\"O is a symbolic link, do not dereference it:
158 .\"O instead return information about the link itself.
160 ¤¬¥·¥ó¥Ü¥ê¥Ã¥¯¥ê¥ó¥¯¤Î¾ì¹ç¤Ï¡¢¤½¤ì¤òé¤ë¤Î¤Ç¤Ï¤Ê¤¯¡¢
161 ¥ê¥ó¥¯¼«¿È¤Ë¤Ä¤¤¤Æ¤Î¾ðÊó¤òÊÖ¤¹¡£
162 .\"O .SH "RETURN VALUE"
164 .\"O On success, (all requested permissions granted)
165 .\"O .BR faccessat ()
167 À®¸ù¤·¤¿¾ì¹ç (Á´¤Æ¤ÎÍ׵ᤵ¤ì¤¿µö²Ä¤¬ÆÀ¤é¤ì¤¿¤é)¡¢
170 .\"O On error, \-1 is returned and
172 .\"O is set to indicate the error.
173 ¥¨¥é¡¼¤Î¾ì¹ç¡¢\-1 ¤¬ÊÖ¤µ¤ì¡¢
175 ¤Ë¤Ï¥¨¥é¡¼¤ò¼¨¤¹Ãͤ¬ÀßÄꤵ¤ì¤ë¡£
178 .\"O The same errors that occur for
180 .\"O can also occur for
181 .\"O .BR faccessat ().
186 .\"O The following additional errors can occur for
187 .\"O .BR faccessat ():
189 ¤Ç¤Ï¡¢¤½¤Î¾¤Ë°Ê²¼¤Î¥¨¥é¡¼¤¬µ¯¤³¤ë:
193 .\"O is not a valid file descriptor.
195 ¤¬Í¸ú¤Ê¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿¤Ç¤Ê¤¤¡£
198 .\"O Invalid flag specified in
201 ¤ËÉÔÀµ¤Ê¥Õ¥é¥°Ãͤ¬»ØÄꤵ¤ì¤¿¡£
207 .\"O is a file descriptor referring to a file other than a directory.
211 ¤¬¥Ç¥£¥ì¥¯¥È¥ê°Ê³°¤Î¥Õ¥¡¥¤¥ë¤ò»²¾È¤¹¤ë¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿¤Ç¤¢¤ë¡£
214 .\"O .BR faccessat ()
215 .\"O was added to Linux in kernel 2.6.16.
217 ¤Ï Linux ¥«¡¼¥Í¥ë 2.6.16 ¤ÇÄɲ䵤줿¡£
218 .\"O .SH "CONFORMING TO"
225 .\"O for an explanation of the need for
226 .\"O .BR faccessat ().
228 ¤¬É¬ÍפÊÍýͳ¤Ë¤Ä¤¤¤Æ¤Ï¡¢
232 .SS glibc ¤Ë¤Ä¤¤¤Æ¤ÎÃí°Õ
236 .\"O .B AT_SYMLINK_NOFOLLOW
237 .\"O flags are actually implemented within the glibc wrapper function for
238 .\"O .BR faccessat ().
241 .B AT_SYMLINK_NOFOLLOW
244 ¤Î glibc ¥é¥Ã¥Ñ¡¼´Ø¿ô¤Ç¼ÂºÝ¤Ë¼ÂÁõ¤µ¤ì¤Æ¤¤¤ë¡£
245 .\"O If either of these flags are specified, then the wrapper function employs
247 .\"O to determine access permissions.
248 ¤³¤ì¤é¤Î¥Õ¥é¥°¤Î¤¤¤º¤ì¤«¤¬»ØÄꤵ¤ì¤¿¾ì¹ç¡¢
249 ¥é¥Ã¥Ñ¡¼´Ø¿ô¤Ï¥¢¥¯¥»¥¹¸¢¤ò·èÄꤹ¤ë¤¿¤á¤Ë
258 .BR path_resolution (7),