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.Sh NAME
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.Sh NAME
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.Nm ln ,
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.Nm ln ,
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.Nm link
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.Nm link
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.Nd make links
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.Nd make soft links (symbolic links, symlinks) and hard links
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.Sh SYNOPSIS
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.Sh SYNOPSIS
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.Nm
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.Nm
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.Op Fl fhinsv
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.Op Fl fhinsv
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.Ar source_file
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.Ar to_filename
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.Op Ar target_file
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.Op Ar from_filename
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.Nm
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.Nm
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.Op Fl fhinsv
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.Op Fl fhinsv
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.Ar source_file ...
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.Ar to_filename ...
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.Ar target_dir
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.Ar dir_filename
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.Nm link
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.Nm link
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.Ar source_file Ar target_file
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.Ar to_existing_filename Ar from_alternate_filename
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.Sh DESCRIPTION
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.Sh DESCRIPTION
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The
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The
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.Nm
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.Nm
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utility creates a new directory entry (linked file) which has the
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utility creates a new filesystem entry which can refer to an existing file
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same modes as the original file.
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.Pq or multiple such entries with the second form .
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It is useful for maintaining multiple copies of a file in many places
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It is useful for maintaining multiple virtual copies of a file in many places
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at once without using up storage for the
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while using filesystem storage for only one file.
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.Dq copies ;
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Two types of links may be made:
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instead, a link
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.Nm ln
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.Dq points
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can make
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to the original copy.
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.Em soft links
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There are two types of links; hard links and symbolic links.
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or
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How a link
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.Em hard links ,
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.Dq points
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while
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to a file is one of the differences between a hard and symbolic link.
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.Nm link
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can make only hard links.
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Note that soft links are also called
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.Em symbolic links
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and
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.Em symlinks .
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The two types are described following the option descriptions.
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.Pp
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.Pp
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The options are as follows:
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The options are as follows:
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.Bl -tag -width flag
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.Bl -tag -width flag
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.It Fl f
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.It Fl f
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If the target file already exists,
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If the
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.Qq from
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file already exists,
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then unlink it so that the link may occur.
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then unlink it so that the link may occur.
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(The
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(The
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.Fl f
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.Fl f
Lines 81-101 Link Here
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options.)
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options.)
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.It Fl h
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.It Fl h
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If the
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If the
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.Ar target_file
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.Ar from_filename
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or
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or
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.Ar target_dir
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.Ar dir_filename
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is a symbolic link, do not follow it.  This is most useful with the
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is a soft link, do not follow it.  This is most useful with the
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.Fl f
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.Fl f
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option, to replace a symlink which may point to a directory.
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option, to replace a soft link which may point to a directory.
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.It Fl i
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.It Fl i
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Cause
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Cause
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.Nm
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.Nm
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to write a prompt to standard error if the target file exists.
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to write a prompt to standard error if the
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.Qq from
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file exists.
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If the response from the standard input begins with the character
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If the response from the standard input begins with the character
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.Sq Li y
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.Sq Li y
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or
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or
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.Sq Li Y ,
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.Sq Li Y ,
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then unlink the target file so that the link may occur.
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then unlink the
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.Qq from
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file so that the link may occur.
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Otherwise, do not attempt the link.
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Otherwise, do not attempt the link.
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(The
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(The
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.Fl i
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.Fl i
Lines 109-115 Link Here
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.Nm
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.Nm
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implementations.
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implementations.
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.It Fl s
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.It Fl s
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Create a symbolic link.
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Create a soft link.
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.It Fl v
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.It Fl v
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Cause
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Cause
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.Nm
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.Nm
Lines 118-164 Link Here
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.Pp
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.Pp
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By default,
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By default,
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.Nm
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.Nm
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makes
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makes hard links.
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.Em hard
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A hard link to a file is indistinguishable from the original filesystem entry;
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links.
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A hard link to a file is indistinguishable from the original directory entry;
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any changes to a file are effectively independent of the name used to reference
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any changes to a file are effectively independent of the name used to reference
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the file.
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the file.
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Unlike with soft links,
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both old and new filesystem entries become links to each other
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.Pq and to other files to which either is hard linked .
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Hard links may not normally refer to directories and may not span filesystems.
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Hard links may not normally refer to directories and may not span filesystems.
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.Pp
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.Pp
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A symbolic link contains the name of the file to
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A soft link contains the name of the file to
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which it is linked.  The referenced file is used when an
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which it is linked.  The referenced file is used when an
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.Xr open  2
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.Xr open  2
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operation is performed on the link.
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operation is performed on the link.
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A
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A
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.Xr stat  2
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.Xr stat  2
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on a symbolic link will return the linked-to file; an
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on a soft link will return the linked-to file; an
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.Xr lstat  2
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.Xr lstat  2
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must be done to obtain information about the link.
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must be done to obtain information about the link.
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The
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The
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.Xr readlink  2
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.Xr readlink  2
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call may be used to read the contents of a symbolic link.
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call may be used to read the contents of a soft link.
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Symbolic links may span filesystems and may refer to directories.
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Soft links may span filesystems and may refer to directories.
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.Pp
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.Pp
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Given one or two arguments,
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Given one or two arguments,
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.Nm
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.Nm
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creates a link to an existing file
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creates a link to an existing file
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.Ar source_file  .
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.Ar to_filename  .
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If
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If
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.Ar target_file
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.Ar from_filename
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is given, the link has that name;
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is given, the link has that name;
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.Ar target_file
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.Ar from_filename
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may also be a directory in which to place the link;
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may also be a directory in which to place the link;
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otherwise it is placed in the current directory.
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otherwise it is placed in the current directory.
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If only the directory is specified, the link will be made
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If only the directory is specified, the link will be made
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to the last component of
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to the last component of
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.Ar source_file  .
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.Ar to_filename  .
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.Pp
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.Pp
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Given more than two arguments,
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Given more than two arguments,
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.Nm
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.Nm
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makes links in
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makes links in
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.Ar target_dir
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.Ar dir_filename
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to all the named source files.
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to all the named
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.Qq to
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files.
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The links made will have the same name as the files being linked to.
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The links made will have the same name as the files being linked to.
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.Pp
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.Pp
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When the utility is called as
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When the utility is called as
Lines 169-174 Link Here
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which performs a
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which performs a
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.Xr link 2
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.Xr link 2
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operation using the two passed arguments.
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operation using the two passed arguments.
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.Sh NOTES
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Soft links require careful use to ensure that the
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.Qq to
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filename is used rather than the
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.Qq from
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filename, and vice-versa.
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Their handling by programs is not completely standardized.
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Some often-followed conventions, notable exceptions,
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and related discussion may be found in
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.Xr symlink 7 .
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.Sh SEE ALSO
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.Sh SEE ALSO
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.Xr link 2 ,
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.Xr link 2 ,
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.Xr lstat 2 ,
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.Xr lstat 2 ,

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