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READLINK(2)		       System Calls Manual		     READLINK(2)

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 descrip-
     tor fd instead of the current working directory.  If readlinkat() is passed
     the  special value AT_FDCWD in the fd parameter, the current working direc-
     tory 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  suc-
     ceeds,  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  sys-
			tem.

     [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 de-
			scriptor open for searching.

     [ENOTDIR]		The path argument is not an absolute path and fd is nei-
			ther AT_FDCWD nor a file descriptor  associated  with  a
			directory.

SEE ALSO
     fhreadlink(2), 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.

FreeBSD 15.1			 March 30, 2020 		     READLINK(2)
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