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readlink(2)
NAME
  readlink - Read the value of a symbolic link

SYNOPSIS
  #include <unistd.h>

  int readlink(
	  const char *path,
	  char *buffer,
	  size_t buf_size );

  The following version of the buf_size argument does not conform to the XSH
  specification and is supported only for backward compatibility:

  int buf_size

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  readlink(): XSH4.2, XSH5.0

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  path
      Specifies the pathname of the destination file or directory.

  buffer
      Points to the user's buffer. The buffer should be at least as large as
      the buf_size parameter.

  buf_size
      Specifies the size of the buffer.

DESCRIPTION
  The readlink() function places the contents of the symbolic link named by
  the path parameter in buffer, which has size buf_size.

  If the actual length of the symbolic link is greater than buf_size, an
  error is returned. The length of a symbolic link will not exceed PATH_MAX.

  [Tru64 UNIX]	If the actual length of the symbolic link is less than
  buf_size, the string copied into the buffer is null terminated.

  For a readlink() function to complete successfully, the calling process
  must have search access to the directory containing the link.

RETURN VALUES
  Upon successful completion, the readlink() function returns a count of
  bytes placed in the buffer (not including any terminating null). If the
  readlink() function fails, the buffer is not modified, a value of -1 is
  returned, and errno is set to indicate the error.

ERRORS
  The readlink() function sets errno to the specified values for the
  following conditions:

  [EACCES]
      Search permission is denied on a component of the path prefix of the
      path parameter, or read permission is denied on the final component of
      the path prefix of the path parameter.

  [EINVAL]
      The file named by the path parameter is not a symbolic link.

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

  [ELOOP]
      Too many symbolic links were encountered in resolving path.

  [ENAMETOOLONG]
      The length of the path parameter exceeds PATH_MAX, or a pathname
      component is longer than NAME_MAX while _POSIX_NO_TRUNC is in effect.

  [ENOENT]
      The file named by the path parameter does not exist or the path
      parameter points to an empty string.

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

  [ERANGE]
      [Tru64 UNIX]  The pathname in the symbolic link is longer than
      buf_size.

  For NFS file access, if the readlink() function fails, errno may also be
  set to one of the following values:

  [EINVAL]
      [Tru64 UNIX]  The owner or group ID is not a value supported by this
      implementation.

  [ESTALE]
      [Tru64 UNIX]  Indicates a stale NFS file handle. An opened file was
      deleted by the server or another client; a client cannot open a file
      because the server has unmounted or unexported the remote directory; or
      the directory that contains an opened file was either unmounted or
      unexported by the server.

SEE ALSO
  Functions: link(2), stat(2), symlink(2), unlink(2)

  Standards: standards(5)

Index for Section 2

Alphabetical listing for R

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