ln/ln.1

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  35 .\"     @(#)ln.1        8.2 (Berkeley) 12/30/93
  36 .\" $FreeBSD: src/bin/ln/ln.1,v 1.25 2002/08/21 17:32:32 trhodes Exp $
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  38 .Dd December 30, 1993
  39 .Dt LN 1
  40 .Os
  41 .Sh NAME
  42 .Nm ln ,
  43 .Nm link
  44 .Nd make links
  45 .Sh SYNOPSIS
  46 .Nm
  47 .Op Fl fhinsv
  48 .Ar source_file
  49 .Op Ar target_file
  50 .Nm
  51 .Op Fl fhinsv
  52 .Ar source_file ...
  53 .Ar target_dir
  54 .Nm link
  55 .Ar source_file Ar target_file
  56 .Sh DESCRIPTION
  57 The
  58 .Nm
  59 utility creates a new directory entry (linked file) which has the
  60 same modes as the original file.
  61 It is useful for maintaining multiple copies of a file in many places
  62 at once without using up storage for the
  63 .Dq copies ;
  64 instead, a link
  65 .Dq points
  66 to the original copy.
  67 There are two types of links; hard links and symbolic links.
  68 How a link
  69 .Dq points
  70 to a file is one of the differences between a hard and symbolic link.
  71 .Pp
  72 The options are as follows:
  73 .Bl -tag -width flag
  74 .It Fl f
  75 If the target file already exists,
  76 then unlink it so that the link may occur.
  77 (The
  78 .Fl f
  79 option overrides any previous
  80 .Fl i
  81 options.)
  82 .It Fl h
  83 If the
  84 .Ar target_file
  85 or
  86 .Ar target_dir
  87 is a symbolic link, do not follow it.  This is most useful with the
  88 .Fl f
  89 option, to replace a symlink which may point to a directory.
  90 .It Fl i
  91 Cause
  92 .Nm
  93 to write a prompt to standard error if the target file exists.
  94 If the response from the standard input begins with the character
  95 .Sq Li y
  96 or
  97 .Sq Li Y ,
  98 then unlink the target file so that the link may occur.
  99 Otherwise, do not attempt the link.
 100 (The
 101 .Fl i
 102 option overrides any previous
 103 .Fl f
 104 options.)
 105 .It Fl n
 106 Same as
 107 .Fl h ,
 108 for compatibility with other
 109 .Nm
 110 implementations.
 111 .It Fl s
 112 Create a symbolic link.
 113 .It Fl v
 114 Cause
 115 .Nm
 116 to be verbose, showing files as they are processed.
 117 .El
 118 .Pp
 119 By default,
 120 .Nm
 121 makes
 122 .Em hard
 123 links.
 124 A hard link to a file is indistinguishable from the original directory entry;
 125 any changes to a file are effectively independent of the name used to reference
 126 the file.
 127 Hard links may not normally refer to directories and may not span file systems.
 128 .Pp
 129 A symbolic link contains the name of the file to
 130 which it is linked.  The referenced file is used when an
 131 .Xr open  2
 132 operation is performed on the link.
 133 A
 134 .Xr stat  2
 135 on a symbolic link will return the linked-to file; an
 136 .Xr lstat  2
 137 must be done to obtain information about the link.
 138 The
 139 .Xr readlink  2
 140 call may be used to read the contents of a symbolic link.
 141 Symbolic links may span file systems and may refer to directories.
 142 .Pp
 143 Given one or two arguments,
 144 .Nm
 145 creates a link to an existing file
 146 .Ar source_file  .
 147 If
 148 .Ar target_file
 149 is given, the link has that name;
 150 .Ar target_file
 151 may also be a directory in which to place the link;
 152 otherwise it is placed in the current directory.
 153 If only the directory is specified, the link will be made
 154 to the last component of
 155 .Ar source_file  .
 156 .Pp
 157 Given more than two arguments,
 158 .Nm
 159 makes links in
 160 .Ar target_dir
 161 to all the named source files.
 162 The links made will have the same name as the files being linked to.
 163 .Pp
 164 When the utility is called as
 165 .Nm link ,
 166 exactly two arguments must be supplied,
 167 neither of which may specify a directory.
 168 No options may be supplied in this simple mode of operation,
 169 which performs a
 170 .Xr link 2
 171 operation using the two passed arguments.
 172 .Sh SEE ALSO
 173 .Xr link 2 ,
 174 .Xr lstat 2 ,
 175 .Xr readlink 2 ,
 176 .Xr stat 2 ,
 177 .Xr symlink 2 ,
 178 .Xr symlink 7
 179 .Sh COMPATIBILITY
 180 The
 181 .Fl h ,
 182 .Fl i ,
 183 .Fl n
 184 and
 185 .Fl v
 186 options are non-standard and their use in scripts is not recommended.
 187 They are provided solely for compatibility with other
 188 .Nm
 189 implementations.
 190 .Sh STANDARDS
 191 The
 192 .Nm
 193 utility conforms to
 194 .St -p1003.2-92 .
 195 .Pp
 196 The simplified
 197 .Nm link
 198 command conforms to
 199 .St -susv2 .
 200 .Sh HISTORY
 201 An
 202 .Nm
 203 command appeared in
 204 .At v1 .