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26 .TH FACCESSAT 2 2010-10-24 "Linux" "Linux Programmer's Manual"
28 faccessat \- check user's permissions of a file relative to a \
29 directory file descriptor
32 .B #include <fcntl.h> /* Definition of AT_* constants */
33 .B #include <unistd.h>
35 .BI "int faccessat(int " dirfd ", const char *" pathname ", int " \
36 mode ", int " flags );
40 Feature Test Macro Requirements for glibc (see
41 .BR feature_test_macros (7)):
50 _XOPEN_SOURCE\ >=\ 700 || _POSIX_C_SOURCE\ >=\ 200809L
60 system call operates in exactly the same way as
62 except for the differences described in this manual page.
64 If the pathname given in
66 is relative, then it is interpreted relative to the directory
67 referred to by the file descriptor
69 (rather than relative to the current working directory of
70 the calling process, as is done by
72 for a relative pathname).
82 is interpreted relative to the current working
83 directory of the calling process (like
93 is constructed by ORing together zero or more of the following values:
96 Perform access checks using the effective user and group IDs.
99 uses the real IDs (like
102 .B AT_SYMLINK_NOFOLLOW
105 is a symbolic link, do not dereference it:
106 instead return information about the link itself.
108 On success, (all requested permissions granted)
111 On error, \-1 is returned and
113 is set to indicate the error.
115 The same errors that occur for
119 The following additional errors can occur for
124 is not a valid file descriptor.
127 Invalid flag specified in
134 is a file descriptor referring to a file other than a directory.
137 was added to Linux in kernel 2.6.16.
143 for an explanation of the need for
148 is subject to the same kinds of races as
156 .B AT_SYMLINK_NOFOLLOW
157 flags are actually implemented within the glibc wrapper function for
159 If either of these flags are specified, then the wrapper function employs
161 to determine access permissions.
167 .BR path_resolution (7),