xref: /minix3/bin/ln/ln.1 (revision c31c70743a3c6ee862ff5dd2a42c11312295e202)

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.\"
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.\"	@(#)ln.1	8.2 (Berkeley) 12/30/93
.\"
.Dd October 29, 2007
.Dt LN 1
.Os
.Sh NAME
.Nm ln
.Nd make links
.Sh SYNOPSIS
.Nm
.Op Fl fhinsv
.Ar source_file
.Op Ar target_file
.Nm
.Op Fl fhinsv
.Ar source_file ... target_dir
.Sh DESCRIPTION
The
.Nm
utility creates a new directory entry (linked file) which has the
same modes as the original file.
It is useful for maintaining multiple copies of a file in many places
at once without using up storage for the
.Dq copies ;
instead, a link
.Dq points
to the original copy.
There are two types of links: hard links and symbolic links.
How a link
.Dq points
to a file is one of the differences between a hard or symbolic link.
.Pp
The options are as follows:
.Bl -tag -width flag
.It Fl f
Unlink any already existing file, permitting the link to occur.
.It Fl h
If the
.Ar target_file
or
.Ar target_dir
is a symbolic link, do not follow it.
This is most useful with the
.Fl f
option, to replace a symlink which may point to a directory.
.It Fl i
Cause
.Nm
to write a prompt to standard error if the target file exists.
If the response from the standard input begins with the character
.Sq Li y
or
.Sq Li Y ,
then unlink the target file so that the link may occur.
Otherwise, do not attempt the link.
(The
.Fl i
option overrides any previous
.Fl f
options.)
.It Fl n
Same as
.Fl h ,
for compatibility with other
.Nm
implementations, namely GNU coreutils.
.It Fl s
Create a symbolic link.
.It Fl v
Cause
.Nm
to be verbose, showing files as they are processed.
.El
.Pp
By default
.Nm
makes
.Em hard
links.
A hard link to a file is indistinguishable from the original directory entry;
any changes to a file are effective independent of the name used to reference
the file.
Hard links may not normally refer to directories and may not span file systems.
.Pp
A symbolic link contains the name of the file to
which it is linked.
The referenced file is used when an
.Xr open 2
operation is performed on the link.
A
.Xr stat 2
on a symbolic link will return the linked-to file; an
.Xr lstat 2
must be done to obtain information about the link.
The
.Xr readlink 2
call may be used to read the contents of a symbolic link.
Symbolic links may span file systems and may refer to directories.
.Pp
Given one or two arguments,
.Nm
creates a link to an existing file
.Ar source_file  .
If
.Ar target_file
is given, the link has that name;
.Ar target_file
may also be a directory in which to place the link;
otherwise it is placed in the current directory.
If only the directory is specified, the link will be made
to the last component of
.Ar source_file  .
.Pp
Given more than two arguments,
.Nm
makes links in
.Ar target_dir
to all the named source files.
The links made will have the same name as the files being linked to.
.Sh SEE ALSO
.Xr link 2 ,
.Xr lstat 2 ,
.Xr readlink 2 ,
.Xr stat 2 ,
.Xr symlink 2 ,
.Xr symlink 7
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.2-92 .
.Pp
The
.Fl v
option is an extension to
.St -p1003.2-92 .
.Sh HISTORY
A
.Nm
utility appeared in
.At v6 .