1.\"- 2.\" Copyright (c) 1980, 1990, 1993 3.\" The Regents of the University of California. All rights reserved. 4.\" 5.\" This code is derived from software contributed to Berkeley by 6.\" the Institute of Electrical and Electronics Engineers, Inc. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)ln.1 8.2 (Berkeley) 12/30/93 33.\" $FreeBSD$ 34.\" 35.Dd June 12, 2017 36.Dt LN 1 37.Os 38.Sh NAME 39.Nm ln , 40.Nm link 41.Nd link files 42.Sh SYNOPSIS 43.Nm 44.Op Fl L | Fl P | Fl s Op Fl F 45.Op Fl f | iw 46.Op Fl hnv 47.Ar source_file 48.Op Ar target_file 49.Nm 50.Op Fl L | Fl P | Fl s Op Fl F 51.Op Fl f | iw 52.Op Fl hnv 53.Ar source_file ... 54.Ar target_dir 55.Nm link 56.Ar source_file Ar target_file 57.Sh DESCRIPTION 58The 59.Nm 60utility creates a new directory entry (linked file) for the file name 61specified by 62.Ar target_file . 63The 64.Ar target_file 65will be created with the same file modes as the 66.Ar source_file . 67It is useful for maintaining multiple copies of a file in many places 68at once without using up storage for the 69.Dq copies ; 70instead, a link 71.Dq points 72to the original copy. 73There are two types of links; hard links and symbolic links. 74How a link 75.Dq points 76to a file is one of the differences between a hard and symbolic link. 77.Pp 78The options are as follows: 79.Bl -tag -width flag 80.It Fl F 81If the target file already exists and is a directory, then remove it 82so that the link may occur. 83The 84.Fl F 85option should be used with either 86.Fl f 87or 88.Fl i 89options. 90If neither 91.Fl f 92nor 93.Fl i 94is specified, 95.Fl f 96is implied. 97The 98.Fl F 99option is a no-op unless 100.Fl s 101is specified. 102.It Fl L 103When creating a hard link to a symbolic link, 104create a hard link to the target of the symbolic link. 105This is the default. 106This option cancels the 107.Fl P 108option. 109.It Fl P 110When creating a hard link to a symbolic link, 111create a hard link to the symbolic link itself. 112This option cancels the 113.Fl L 114option. 115.It Fl f 116If the target file already exists, 117then unlink it so that the link may occur. 118(The 119.Fl f 120option overrides any previous 121.Fl i 122and 123.Fl w 124options.) 125.It Fl h 126If the 127.Ar target_file 128or 129.Ar target_dir 130is a symbolic link, do not follow it. 131This is most useful with the 132.Fl f 133option, to replace a symlink which may point to a directory. 134.It Fl i 135Cause 136.Nm 137to write a prompt to standard error if the target file exists. 138If the response from the standard input begins with the character 139.Sq Li y 140or 141.Sq Li Y , 142then unlink the target file so that the link may occur. 143Otherwise, do not attempt the link. 144(The 145.Fl i 146option overrides any previous 147.Fl f 148options.) 149.It Fl n 150Same as 151.Fl h , 152for compatibility with other 153.Nm 154implementations. 155.It Fl s 156Create a symbolic link. 157.It Fl v 158Cause 159.Nm 160to be verbose, showing files as they are processed. 161.It Fl w 162Warn if the source of a symbolic link does not currently exist. 163.El 164.Pp 165By default, 166.Nm 167makes 168.Em hard 169links. 170A hard link to a file is indistinguishable from the original directory entry; 171any changes to a file are effectively independent of the name used to reference 172the file. 173Directories may not be hardlinked, and hard links may not span file systems. 174.Pp 175A symbolic link contains the name of the file to 176which it is linked. 177The referenced file is used when an 178.Xr open 2 179operation is performed on the link. 180A 181.Xr stat 2 182on a symbolic link will return the linked-to file; an 183.Xr lstat 2 184must be done to obtain information about the link. 185The 186.Xr readlink 2 187call may be used to read the contents of a symbolic link. 188Symbolic links may span file systems and may refer to directories. 189.Pp 190Given one or two arguments, 191.Nm 192creates a link to an existing file 193.Ar source_file . 194If 195.Ar target_file 196is given, the link has that name; 197.Ar target_file 198may also be a directory in which to place the link; 199otherwise it is placed in the current directory. 200If only the directory is specified, the link will be made 201to the last component of 202.Ar source_file . 203.Pp 204Given more than two arguments, 205.Nm 206makes links in 207.Ar target_dir 208to all the named source files. 209The links made will have the same name as the files being linked to. 210.Pp 211When the utility is called as 212.Nm link , 213exactly two arguments must be supplied, 214neither of which may specify a directory. 215No options may be supplied in this simple mode of operation, 216which performs a 217.Xr link 2 218operation using the two passed arguments. 219.Sh EXAMPLES 220Create a symbolic link named 221.Pa /home/src 222and point it to 223.Pa /usr/src : 224.Pp 225.Dl # ln -s /usr/src /home/src 226.Pp 227Hard link 228.Pa /usr/local/bin/fooprog 229to file 230.Pa /usr/local/bin/fooprog-1.0 : 231.Pp 232.Dl # ln /usr/local/bin/fooprog-1.0 /usr/local/bin/fooprog 233.Pp 234As an exercise, try the following commands: 235.Bd -literal -offset indent 236# ls -i /bin/[ 23711553 /bin/[ 238# ls -i /bin/test 23911553 /bin/test 240.Ed 241.Pp 242Note that both files have the same inode; that is, 243.Pa /bin/[ 244is essentially an alias for the 245.Xr test 1 246command. 247This hard link exists so 248.Xr test 1 249may be invoked from shell scripts, for example, using the 250.Li "if [ ]" 251construct. 252.Pp 253In the next example, the second call to 254.Nm 255removes the original 256.Pa foo 257and creates a replacement pointing to 258.Pa baz : 259.Bd -literal -offset indent 260# mkdir bar baz 261# ln -s bar foo 262# ln -shf baz foo 263.Ed 264.Pp 265Without the 266.Fl h 267option, this would instead leave 268.Pa foo 269pointing to 270.Pa bar 271and inside 272.Pa foo 273create a new symlink 274.Pa baz 275pointing to itself. 276This results from directory-walking. 277.Pp 278An easy rule to remember is that the argument order for 279.Nm 280is the same as for 281.Xr cp 1 : 282The first argument needs to exist, the second one is created. 283.Sh COMPATIBILITY 284The 285.Fl h , 286.Fl i , 287.Fl n , 288.Fl v 289and 290.Fl w 291options are non-standard and their use in scripts is not recommended. 292They are provided solely for compatibility with other 293.Nm 294implementations. 295.Pp 296The 297.Fl F 298option is a 299.Fx 300extension and should not be used in portable scripts. 301.Sh SEE ALSO 302.Xr link 2 , 303.Xr lstat 2 , 304.Xr readlink 2 , 305.Xr stat 2 , 306.Xr symlink 2 , 307.Xr symlink 7 308.Sh STANDARDS 309The 310.Nm 311utility conforms to 312.St -p1003.2-92 . 313.Pp 314The simplified 315.Nm link 316command conforms to 317.St -susv2 . 318.Sh HISTORY 319An 320.Nm 321command appeared in 322.At v1 . 323