HPUX ln[1]
ln(1) ln(1)
NAME
ln - link files and directories
SYNOPSIS
ln [-f] [-i] [-s] file1 new_file
ln [-f] [-i] [-s] file1 [file2 ...] dest_directory
ln [-f] [-i] [-s] directory1 [directory2 ...] dest_directory
DESCRIPTION
ln links:
o file1 to a new or existing new_file,
o file1 to a new or existing file named file1 in existing
dest_directory,
o file1, file2, ... to new or existing files of the same name
in existing dest_directory,
o directory1, directory2, ... to new directories of the same
name in existing dest_directory,
o or creates symbolic links between files or between
directories.
If links are to dest_directory, corresponding file or directory names
in that directory are linked to file1, file2, ..., or directory1,
directory2, ..., etc., as appropriate. If two or more existing files
or directories (excluding destination file name new_file) are
specified, the destination must be a directory. If new_file already
exists as a regular file (or link to another file), its contents (or
the existing link) and its ACL are destroyed only if the -f option is
specified. The ACL on the new_file after the link is the same as that
of the source_file file.
If the -f and -i options are specified and the link being created is
the name of an existing link or ordinary file and the access
permissions of the file forbid writing, ln asks permission to
overwrite the file. If the access permissions of the directory forbid
writing, ln aborts and returns with the error message cannot unlink
new_file (even if the file is an ordinary file and not a link to
another file). When asking for permission to overwrite an existing
file or link, ln prints the mode (see chmod(2) and Access Control
Lists below), followed by the first letters of the words yes and no in
the current native language, prompting for a response, and reading one
line from the standard input. If the response is affirmative and is
permissible, the operation occurs; if not, the command proceeds to the
next source file, if any.
Hard links and symbolic links are created with the same ownerships and
permissions as the file or directory to which they are linked. If
ownership or permissions are changed on a link, file, or directory,
the same changes appear on corresponding hard and symbolic links.
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ln(1) ln(1)
ln does not permit hard links to a directory.
If file1 is a file and new_file is a link to an existing file or an
existing file with other links, new_file is disassociated from the
existing file and links and linked to file1. When ln creates a link
to a new or existing filename, ownerships and permissions are always
identical to those for the file to which it is linked. If chown,
chgrp, or chmod is used to change ownership or permissions of a file
or link, the change applies to the file and all associated links. The
last modification time and last access time of the file and all
associated links are identical (see chown(1), chgrp(1), and chmod(1)).
For a discussion of symbolic links, see symlink(4).
Options
ln recognizes the following options:
-f Force existing destination pathnames to be removed to allow
the link.
-i Write a prompt to the standard error output requesting
confirmation for each link that would overwrite an existing
file. This option takes effect only if used in conjunction
with the -f option.
-s Cause ln to create symbolic links instead of the usual hard
links. A symbolic link contains the name of the file to
which it is linked (see WARNINGS below). The referenced
file is used when an open() operation is performed on the
link (see open(2)). A stat() on a symbolic link returns the
linked-to file; an lstat() must be performed to obtain
information about the link (see stat(2)). A readlink() call
can be used to read the contents of the symbolic link (see
readlink(2)). Symbolic links can span file systems and can
refer to directories.
Access Control Lists (ACLs)
If optional ACL entries are associated with new_file, ln displays a
plus sign (+) after the access mode when asking permission to
overwrite the file.
If new_file is a new file, it inherits the access control list of
file1, altered to reflect any difference in ownership between the two
files (see acl(5)).
EXTERNAL INFLUENCES
Environment Variables
LC_CTYPE determines the interpretation of text as single and/or
multi-byte characters.
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LANG and LC_CTYPE determine the local language equivalent of y (for
yes/no queries).
LANG determines the language in which messages are displayed.
If LC_CTYPE is not specified in the environment or is set to the empty
string, the value of LANG is used as a default for each unspecified or
empty variable. If LANG is not specified or is set to the empty
string, a default of "C" (see lang(5)) is used instead of LANG. If
any internationalization variable contains an invalid setting, ln
behaves as if all internationalization variables are set to "C". See
environ(5).
International Code Set Support
Single- and multi-byte character code sets are supported.
EXAMPLES
The following command creates filenames new_file1 and new_file2 in
dest_dir which are linked back to the original files file1 and file2:
ln file1 file2 dest_dir
If new_file1 and/or new_file2 exists, it is removed and replaced by a
link to file1 or file2, respectively. If existing new_file1 or
new_file2 is a link to another file or a file with links, the existing
file remains. Only the link to new_file is broken and replaced by a
new link to the file1 or file2.
WARNINGS
ln does not create hard links across file systems.
Use care in defining symbolic links. Unless dest_directory is the
current working directory or the existing file is given in absolute
path name form, it is very easy to define an endless loop, as in the
case of:
cd /users/my_dir
ln -s file1 /dest_directory
which links the new file to itself instead of the intended
/users/my_dir/file1.
DEPENDENCIES
NFS Access control lists of networked files are summarized (as
returned in st_mode by stat()), but not copied to the new file.
When using ln on such files, a + is not printed after the mode
value when asking for permission to overwrite a file.
AUTHOR
ln was developed by AT&T, the University of California, Berkeley and
HP.
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SEE ALSO
cp(1), cpio(1), mv(1), rm(1), link(1M), readlink(2), stat(2),
symlink(2), symlink(4), acl(5).
STANDARDS CONFORMANCE
ln: SVID2, XPG2, XPG3, POSIX.2
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