file_cmds/ln/ln.1

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  32 .\"     @(#)ln.1        8.2 (Berkeley) 12/30/93
  33 .\" $FreeBSD: src/bin/ln/ln.1,v 1.31 2006/02/14 11:08:05 glebius Exp $
  34 .\"
  35 .Dd July 12, 2019
  36 .Dt LN 1
  37 .Os
  38 .Sh NAME
  39 .Nm link ,
  40 .Nm ln
  41 .Nd make links
  42 .Sh SYNOPSIS
  43 .Nm ln
  44 .Op Fl Ffhinsv
  45 .Ar source_file
  46 .Op Ar link_name
  47 .Nm ln
  48 .Op Fl Ffhinsv
  49 .Ar source_file ...
  50 .Ar link_dirname
  51 .Nm link
  52 .Ar source_file Ar link_name
  53 .Sh DESCRIPTION
  54 The
  55 .Nm ln
  56 utility creates a new directory entry (linked file) which has the
  57 same modes as the original file.
  58 It is useful for maintaining multiple copies of a file in many places
  59 at once without using up storage for the
  60 .Dq copies ;
  61 instead, a link
  62 .Dq points
  63 to the original copy.
  64 There are two types of links; hard links and symbolic links.
  65 How a link
  66 .Dq points
  67 to a file is one of the differences between a hard and symbolic link.
  68 .Pp
  69 The options are as follows:
  70 .Bl -tag -width flag
  71 .\" ==========
  72 .It Fl F
  73 If the proposed link (link_name) already exists and is a directory, then remove it
  74 so that the link may occur.
  75 The
  76 .Fl F
  77 option should be used with either
  78 .Fl f
  79 or
  80 .Fl i
  81 options.
  82 If none is specified,
  83 .Fl f
  84 is implied.
  85 The
  86 .Fl F
  87 option is a no-op unless
  88 .Fl s
  89 option is specified.
  90 .It Fl h
  91 If the
  92 .Ar link_name
  93 or
  94 .Ar link_dirname
  95 is a symbolic link, do not follow it.
  96 This is most useful with the
  97 .Fl f
  98 option, to replace a symlink which may point to a directory.
  99 .\" ==========
 100 .It Fl f
 101 If the proposed link (link_name) already exists,
 102 then unlink it so that the link may occur.
 103 (The
 104 .Fl f
 105 option overrides any previous
 106 .Fl i
 107 options.)
 108 .\" ==========
 109 .It Fl i
 110 Cause
 111 .Nm ln
 112 to write a prompt to standard error if the proposed link exists.
 113 If the response from the standard input begins with the character
 114 .Sq Li y
 115 or
 116 .Sq Li Y ,
 117 then unlink the proposed link so that the link may occur.
 118 Otherwise, do not attempt the link.
 119 (The
 120 .Fl i
 121 option overrides any previous
 122 .Fl f
 123 options.)
 124 .\" ==========
 125 .It Fl n
 126 Same as
 127 .Fl h ,
 128 for compatibility with other
 129 .Nm ln
 130 implementations.
 131 .\" ==========
 132 .It Fl s
 133 Create a symbolic link.
 134 .\" ==========
 135 .It Fl v
 136 Cause
 137 .Nm ln
 138 to be verbose, showing files as they are processed.
 139 .El
 140 .Pp
 141 By default,
 142 .Nm ln
 143 makes
 144 .Em hard
 145 links.
 146 A hard link to a file is indistinguishable from the original directory entry;
 147 any changes to a file are effectively independent of the name used to reference
 148 the file.
 149 Hard links may not normally refer to directories and may not span file systems.
 150 .Pp
 151 A symbolic link contains the name of the file to
 152 which it is linked.
 153 The referenced file is used when an
 154 .Xr open 2
 155 operation is performed on the link.
 156 A
 157 .Xr stat 2
 158 on a symbolic link will return the linked-to file; an
 159 .Xr lstat 2
 160 must be done to obtain information about the link.
 161 The
 162 .Xr readlink 2
 163 call may be used to read the contents of a symbolic link.
 164 Symbolic links may span file systems and may refer to directories.
 165 .Pp
 166 Given one or two arguments,
 167 .Nm ln
 168 creates a link to an existing file
 169 .Ar source_file .
 170 If
 171 .Ar link_name
 172 is given, the link has that name;
 173 .Ar link_name
 174 may also be a directory in which to place the link;
 175 otherwise it is placed in the current directory.
 176 If only the directory is specified, the link will be made
 177 to the last component of
 178 .Ar source_file .
 179 .Pp
 180 Given more than two arguments,
 181 .Nm ln
 182 makes links in
 183 .Ar link_dirname
 184 to all the named source files.
 185 The links made will have the same name as the files being linked to.
 186 .Pp
 187 When the utility is called as
 188 .Nm link ,
 189 exactly two arguments must be supplied,
 190 neither of which may specify a directory.
 191 No options may be supplied in this simple mode of operation,
 192 which performs a
 193 .Xr link 2
 194 operation using the two passed arguments.
 195 .Sh COMPATIBILITY
 196 The
 197 .Fl h ,
 198 .Fl i ,
 199 .Fl n
 200 and
 201 .Fl v
 202 options are non-standard and their use in scripts is not recommended.
 203 They are provided solely for compatibility with other
 204 .Nm ln
 205 implementations.
 206 .Pp
 207 The
 208 .Fl F
 209 option is
 210 .Fx
 211 extention and should not be used in portable scripts.
 212 .Sh SEE ALSO
 213 .Xr link 2 ,
 214 .Xr lstat 2 ,
 215 .Xr readlink 2 ,
 216 .Xr stat 2 ,
 217 .Xr symlink 2 ,
 218 .Xr symlink 7
 219 .Sh STANDARDS
 220 The
 221 .Nm ln
 222 utility conforms to
 223 .St -p1003.2-92 .
 224 .Pp
 225 The simplified
 226 .Nm link
 227 command conforms to
 228 .St -susv2 .
 229 .Sh HISTORY
 230 An
 231 .Nm ln
 232 command appeared in
 233 .At v1 .