ln(1) USER COMMANDS ln(1)
NAME
ln - make hard or symbolic links to files
SYNOPSIS
/usr/ucb/ln [ -fs ] filename [ linkname ]
/usr/ucb/ln [ -fs ] pathname... directory
DESCRIPTION
/usr/ucb/ln creates an additional directory entry, called a
link, to a file or directory. Any number of links can be
assigned to a file. The number of links does not affect
other file attributes such as size, protections, data, etc.
filename is the name of the original file or directory.
linkname is the new name to associate with the file or
filename. If linkname is omitted, the last component of
filename is used as the name of the link. If the last argu-
ment is the name of a directory, symbolic links are made in
that directory for each pathname argument; /usr/ucb/ln uses
the last component of each pathname as the name of each link
in the named directory. A hard link (the default) is a
standard directory entry just like the one made when the
file was created. Hard links can only be made to existing
files. Hard links cannot be made across file systems (disk
partitions, mounted file systems). To remove a file, all
hard links to it must be removed, including the name by
which it was first created; removing the last hard link
releases the inode associated with the file. A symbolic
link, made with the -s option, is a special directory entry
that points to another named file. Symbolic links can span
file systems and point to directories. In fact, you can
create a symbolic link that points to a file that is
currently absent from the file system; removing the file
that it points to does not affect or alter the symbolic link
itself. A symbolic link to a directory behaves differently
than you might expect in certain cases. While an ls(1V) on
such a link displays the files in the pointed-to directory,
an `ls -l' displays information about the link itself:
example% /usr/ucb/ln -s dir link
example% ls link
file1 file2 file3 file4
example% ls -l link
lrwxrwxrwx 1 user 7 Jan 11 23:27 link -> dir
When you cd(1) to a directory through a symbolic link, you
wind up in the pointed-to location within the file system.
This means that the parent of the new working directory is
not the parent of the symbolic link, but rather, the parent
of the pointed-to directory. For instance, in the following
case the final working directory is /usr and not
/home/user/linktest.
example% pwd
/home/user/linktest
example% /usr/ucb/ln -s /var/tmp symlink
Last change: BSD Compatibility Package 1
ln(1) USER COMMANDS ln(1)
example% cd symlink
example% cd ..
example% pwd
/usr
C shell user's can avoid any resulting navigation problems
by using the pushd and popd built-in commands instead of cd.
OPTIONS
-f Force a hard link to a directory - this option is only
available to the super-user.
-s Create a symbolic link or links.
EXAMPLE
The commands below illustrate the effects of the different
forms of the /usr/ucb/ln command:
example% /usr/ucb/ln file link
example% ls -F file link
file link
example% /usr/ucb/ln -s file symlink
example% ls -F file symlink
file symlink@
example% ls -li file link symlink
10606 -rw-r--r-- 2 user 0 Jan 12 00:06 file
10606 -rw-r--r-- 2 user 0 Jan 12 00:06 link
10607 lrwxrwxrwx 1 user 4 Jan 12 00:06 symlink -> file
example% /usr/ucb/ln -s nonesuch devoid
example% ls -F devoid
devoid@
example% cat devoid
devoid: No such file or directory
example% /usr/ucb/ln -s /proto/bin/* /tmp/bin
example% ls -F /proto/bin /tmp/bin
/proto/bin:
x* y* z*
/tmp/bin:
x@ y@ z@
SEE ALSO
cp(1), ls(1), mv(1), rm(1) in the User's Reference Manual.
link(2), readlink(2), stat(2), symlink(2) in the
Programmer's Reference Manual.
NOTES
When the last argument is a directory, simple basenames
should not be used for pathname arguments. If a basename is
used, the resulting symbolic link points to itself:
example% /usr/ucb/ln -s file /tmp
example% ls -l /tmp/file
lrwxrwxrwx 1 user 4 Jan 12 00:16 /tmp/file -> file
Last change: BSD Compatibility Package 2
ln(1) USER COMMANDS ln(1)
example% cat /tmp/file
/tmp/file: Too many levels of symbolic links
To avoid this problem, use full pathnames, or prepend a
reference to the PWD variable to files in the working direc-
tory:
example% rm /tmp/file
example% /usr/ucb/ln -s $PWD/file /tmp
lrwxrwxrwx 1 user
4 Jan 12 00:16 /tmp/file -> /home/user/subdir/file
Last change: BSD Compatibility Package 3