1 .\" This manpage is Copyright (C) 2006, Michael Kerrisk
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26 .TH FCHMODAT 2 2012-05-22 "Linux" "Linux Programmer's Manual"
28 fchmodat \- change permissions of a file relative to a directory \
32 .BR "#include <fcntl.h>" " /* Definition of AT_* constants */"
33 .B #include <sys/stat.h>
35 .BI "int fchmodat(int " dirfd ", const char *" pathname ", mode_t " \
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 can either be 0, or include the following flag:
95 .B AT_SYMLINK_NOFOLLOW
98 is a symbolic link, do not dereference it:
99 instead operate on the link itself.
100 This flag is not currently implemented.
105 On error, \-1 is returned and
107 is set to indicate the error.
109 The same errors that occur for
113 The following additional errors can occur for
118 is not a valid file descriptor.
121 Invalid flag specified in
128 is a file descriptor referring to a file other than a directory.
133 .BR AT_SYMLINK_NOFOLLOW ,
134 which is not supported.
137 was added to Linux in kernel 2.6.16;
138 library support was added to glibc in version 2.4.
144 for an explanation of the need for
147 The GNU C library wrapper function implements the POSIX-specified
148 interface described in this page.
149 This interface differs from the underlying Linux system call, which does
157 .BR path_resolution (7),