NAMEreadlinkat - read value of a symbolic link relative to a directory file descriptor
SYNOPSIS#include <fcntl.h> /* Definition of AT_* constants */ #include <unistd.h> int readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): readlinkat(): Since glibc 2.10: _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L Before glibc 2.10: _ATFILE_SOURCE
DESCRIPTIONThe readlinkat() system call operates in exactly the same way as readlink(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 readlink(2) for a relative pathname). If pathname is relative and dirfd is the special value AT_FDCWD, then pathname is interpreted relative to the current working directory of the calling process (like readlink(2)). If pathname is absolute, then dirfd is ignored.
RETURN VALUEOn success, readlinkat() returns the number of bytes placed in buf. On error, -1 is returned and errno is set to indicate the error.
ERRORSThe same errors that occur for readlink(2) can also occur for readlinkat(). The following additional errors can occur for readlinkat(): EBADF dirfd is not a valid file descriptor. ENOTDIR pathname is relative and dirfd is a file descriptor referring to a file other than a directory.
VERSIONSreadlinkat() was added to Linux in kernel 2.6.16.
NOTESSee openat(2) for an explanation of the need for readlinkat().
SEE ALSOopenat(2), readlink(2), path_resolution(7)
COLOPHONThis page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at //www.kernel.org/doc/man-pages/. READLINKAT(2)