NAME

     readlink, readlinkat — read value of a symbolic link

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <unistd.h>

     ssize_t
     readlink(const char *restrict path, char *restrict buf, size_t bufsiz);

     ssize_t
     readlinkat(int fd, const char *restrict path, char *restrict buf, size_t bufsize);

DESCRIPTION

     The readlink() system call places the contents of the symbolic link path in the buffer buf,
     which has size bufsiz.  The readlink() system call does not append a NUL character to buf.

     The readlinkat() system call is equivalent to readlink() except in the case where path
     specifies a relative path.  In this case the symbolic link whose content is read relative to
     the directory associated with the file descriptor fd instead of the current working
     directory.  If readlinkat() is passed the special value AT_FDCWD in the fd parameter, the
     current working directory is used and the behavior is identical to a call to readlink().

RETURN VALUES

     The call returns the count of characters placed in the buffer if it succeeds, or a -1 if an
     error occurs, placing the error code in the global variable errno.

ERRORS

     The readlink() system call will fail if:

     [ENOTDIR]          A component of the path prefix is not a directory.

     [ENAMETOOLONG]     A component of a pathname exceeded 255 characters, or an entire path name
                        exceeded 1023 characters.

     [ENOENT]           The named file does not exist.

     [EACCES]           Search permission is denied for a component of the path prefix.

     [ELOOP]            Too many symbolic links were encountered in translating the pathname.

     [EINVAL]           The named file is not a symbolic link.

     [EIO]              An I/O error occurred while reading from the file system.

     [EINTEGRITY]       Corrupted data was detected while reading from the file system.

     [EFAULT]           The buf argument extends outside the process's allocated address space.

     In addition to the errors returned by the readlink(), the readlinkat() may fail if:

     [EBADF]            The path argument does not specify an absolute path and the fd argument
                        is neither AT_FDCWD nor a valid file descriptor open for searching.

     [ENOTDIR]          The path argument is not an absolute path and fd is neither AT_FDCWD nor
                        a file descriptor associated with a directory.

SEE ALSO

     lstat(2), stat(2), symlink(2), symlink(7)

STANDARDS

     The readlinkat() system call follows The Open Group Extended API Set 2 specification.

HISTORY

     The readlink() system call appeared in 4.2BSD.  The readlinkat() system call appeared in
     FreeBSD 8.0.