readlink(2) [netbsd man page]

READLINK(2)						      BSD System Calls Manual						       READLINK(2)

NAME

     readlink -- 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);

DESCRIPTION

     readlink() places the contents of the symbolic link path in the buffer buf, which has size bufsiz.  readlink() does not append a NUL charac-
     ter to buf.

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.

EXAMPLES

     A typical use is illustrated in the following piece of code which reads the contents of a symbolic link named /symbolic/link and stores them
     as null-terminated string:

	   #include <limits.h>
	   #include <unistd.h>

	   char buf[PATH_MAX];
	   ssize_t len;

	   if ((len = readlink("/symbolic/link", buf, sizeof(buf)-1)) == -1)
		   error handling;
	   buf[len] = '';

ERRORS

     readlink() will fail if:

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

     [ENAMETOOLONG]	A component of a pathname exceeded {NAME_MAX} characters, or an entire path name exceeded {PATH_MAX} 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.

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

SEE ALSO

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

STANDARDS

     The readlink() function conforms to IEEE Std 1003.1-2001 (``POSIX.1'').

HISTORY

     The readlink() function appeared in 4.2BSD.  The type returned was changed from int to ssize_t in NetBSD 2.1.

BSD
								   May 11, 2004 							       BSD

readlink(2)							   System Calls 						       readlink(2)

NAME

       readlink - read the contents of a symbolic link

SYNOPSIS

       #include <unistd.h>

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

DESCRIPTION

       The  readlink() function places the contents of the symbolic link referred to by path in the buffer buf which has size bufsiz.  If the num-
       ber of bytes in the symbolic link is less than bufsiz, the contents of the remainder of buf are left unchanged. If the buf argument is  not
       large enough to contain the link content, the first bufsize bytes are placed in buf.

RETURN VALUES

       Upon  successful  completion,  readlink()  returns  the	count of bytes placed in the buffer.  Otherwise, it returns  -1, leaves the buffer
       unchanged, and sets errno to indicate the error.

ERRORS

       The readlink() function will fail if:

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

       EFAULT	       path or buf points to an illegal address.

       EINVAL	       The path argument names a file that is not a symbolic link.

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

       ENOENT	       A component of path does not name an existing file or path is an empty string.

       ELOOP	       A loop exists in symbolic links encountered during resolution of the path argument.

       ENAMETOOLONG    The length of path exceeds {PATH_MAX}, or a pathname component is  longer  than	{NAME_MAX}  while  _POSIX_NO_TRUNC  is	in
		       effect.

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

       ENOSYS	       The file system does not support symbolic links.

       The readlink() function may fail if:

       EACCES	       Read permission is denied for the directory.

       ELOOP	       More than {SYMLOOP_MAX} symbolic links were encountered in resolving path.

       ENAMETOOLONG    As  a  result  of  encountering	a symbolic link in resolution of the path argument, the length of the substituted pathname
		       string exceeded {PATH_MAX}.

USAGE

       Portable applications should not assume that the returned contents of the symbolic link are null-terminated.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Async-Signal-Safe 	   |
       +-----------------------------+-----------------------------+

SEE ALSO

       stat(2), symlink(2), attributes(5), standards(5)

SunOS 5.10							    1 Dec 2003							       readlink(2)