NAME
fchmodat - change permissions of a file relative to a directory file descriptor SYNOPSIS
#include
/* Definition of AT* constants */ #include
int fchmodat(int dirfd, const char *pathname, modet mode, int flags); Feature Test Macro Requirements for glibc (see featuretestmacros(7)): fchmodat(): Since glibc 2.10: XOPENSOURCE >= 700 || POSIXCSOURCE >= 200809L Before glibc 2.10: ATFILESOURCE DESCRIPTION The fchmodat() system call operates in exactly the same way as chmod(2), except for the differences described in this manual page. If the pathname given in pathname is relative, then it is interpreted relative to the directory referred to by the file descriptor dirfd (rather than relative to the current working directory of the calling process, as is done by chmod(2) for a relative pathname). If pathname is relative and dirfd is the special value ATFDCWD, then pathname is interpreted relative to the current working directory of the calling process (like chmod(2)). If pathname is absolute, then dirfd is ignored. flags can either be 0, or include the following flag: ATSYMLINKNOFOLLOW If pathname is a symbolic link, do not dereference it: instead operate on the link itself. This flag is not currently imple‐ mented. RETURN VALUE On success, fchmodat() returns 0. On error, -1 is returned and errno is set to indicate the error. ERRORS The same errors that occur for chmod(2) can also occur for fchmodat(). The following additional errors can occur for fchmodat(): EBADF dirfd is not a valid file descriptor. EINVAL Invalid flag specified in flags. ENOTDIR pathname is relative and dirfd is a file descriptor referring to a file other than a directory. ENOTSUP flags specified ATSYMLINKNOFOLLOW, which is not supported. VERSIONS fchmodat() was added to Linux in kernel 2.6.16; library support was added to glibc in version 2.4. CONFORMING TO
POSIX.1-2008. NOTES See openat(2) for an explanation of the need for fchmodat().
The GNU C library wrapper function implements the POSIX-specified interface described in this page. This interface differs from the underlying Linux system call, which does not have a flags argument. SEE ALSO chmod(2), openat(2), pathresolution(7), symlink(7) COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2012-05-22 FCHMODAT(2)