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.\" 34.Dd June 12, 2017 35.Dt LN 1 36.Os 37.Sh NAME 38.Nm ln , 39.Nm link 40.Nd link files 41.Sh SYNOPSIS 42.Nm 43.Op Fl L | Fl P | Fl s Op Fl F 44.Op Fl f | iw 45.Op Fl hnv 46.Ar source_file 47.Op Ar target_file 48.Nm 49.Op Fl L | Fl P | Fl s Op Fl F 50.Op Fl f | iw 51.Op Fl hnv 52.Ar source_file ... 53.Ar target_dir 54.Nm link 55.Ar source_file Ar target_file 56.Sh DESCRIPTION 57The 58.Nm 59utility creates a new directory entry (linked file) for the file name 60specified by 61.Ar target_file . 62The 63.Ar target_file 64will be created with the same file modes as the 65.Ar source_file . 66It is useful for maintaining multiple copies of a file in many places 67at once without using up storage for the 68.Dq copies ; 69instead, a link 70.Dq points 71to the original copy. 72There are two types of links; hard links and symbolic links. 73How a link 74.Dq points 75to a file is one of the differences between a hard and symbolic link. 76.Pp 77The options are as follows: 78.Bl -tag -width flag 79.It Fl F 80If the target file already exists and is a directory, then remove it 81so that the link may occur. 82The 83.Fl F 84option should be used with either 85.Fl f 86or 87.Fl i 88options. 89If neither 90.Fl f 91nor 92.Fl i 93is specified, 94.Fl f 95is implied. 96The 97.Fl F 98option is a no-op unless 99.Fl s 100is specified. 101.It Fl L 102When creating a hard link to a symbolic link, 103create a hard link to the target of the symbolic link. 104This is the default. 105This option cancels the 106.Fl P 107option. 108.It Fl P 109When creating a hard link to a symbolic link, 110create a hard link to the symbolic link itself. 111This option cancels the 112.Fl L 113option. 114.It Fl f 115If the target file already exists, 116then unlink it so that the link may occur. 117(The 118.Fl f 119option overrides any previous 120.Fl i 121and 122.Fl w 123options.) 124.It Fl h 125If the 126.Ar target_file 127or 128.Ar target_dir 129is a symbolic link, do not follow it. 130This is most useful with the 131.Fl f 132option, to replace a symlink which may point to a directory. 133.It Fl i 134Cause 135.Nm 136to write a prompt to standard error if the target file exists. 137If the response from the standard input begins with the character 138.Sq Li y 139or 140.Sq Li Y , 141then unlink the target file so that the link may occur. 142Otherwise, do not attempt the link. 143(The 144.Fl i 145option overrides any previous 146.Fl f 147options.) 148.It Fl n 149Same as 150.Fl h , 151for compatibility with other 152.Nm 153implementations. 154.It Fl s 155Create a symbolic link. 156.It Fl v 157Cause 158.Nm 159to be verbose, showing files as they are processed. 160.It Fl w 161Warn if the source of a symbolic link does not currently exist. 162.El 163.Pp 164By default, 165.Nm 166makes 167.Em hard 168links. 169A hard link to a file is indistinguishable from the original directory entry; 170any changes to a file are effectively independent of the name used to reference 171the file. 172Directories may not be hardlinked, and hard links may not span file systems. 173.Pp 174A symbolic link contains the name of the file to 175which it is linked. 176The referenced file is used when an 177.Xr open 2 178operation is performed on the link. 179A 180.Xr stat 2 181on a symbolic link will return the linked-to file; an 182.Xr lstat 2 183must be done to obtain information about the link. 184The 185.Xr readlink 2 186call may be used to read the contents of a symbolic link. 187Symbolic links may span file systems and may refer to directories. 188.Pp 189Given one or two arguments, 190.Nm 191creates a link to an existing file 192.Ar source_file . 193If 194.Ar target_file 195is given, the link has that name; 196.Ar target_file 197may also be a directory in which to place the link; 198otherwise it is placed in the current directory. 199If only the directory is specified, the link will be made 200to the last component of 201.Ar source_file . 202.Pp 203Given more than two arguments, 204.Nm 205makes links in 206.Ar target_dir 207to all the named source files. 208The links made will have the same name as the files being linked to. 209.Pp 210When the utility is called as 211.Nm link , 212exactly two arguments must be supplied, 213neither of which may specify a directory. 214No options may be supplied in this simple mode of operation, 215which performs a 216.Xr link 2 217operation using the two passed arguments. 218.Sh EXAMPLES 219Create a symbolic link named 220.Pa /home/src 221and point it to 222.Pa /usr/src : 223.Pp 224.Dl # ln -s /usr/src /home/src 225.Pp 226Hard link 227.Pa /usr/local/bin/fooprog 228to file 229.Pa /usr/local/bin/fooprog-1.0 : 230.Pp 231.Dl # ln /usr/local/bin/fooprog-1.0 /usr/local/bin/fooprog 232.Pp 233As an exercise, try the following commands: 234.Bd -literal -offset indent 235# ls -i /bin/[ 23611553 /bin/[ 237# ls -i /bin/test 23811553 /bin/test 239.Ed 240.Pp 241Note that both files have the same inode; that is, 242.Pa /bin/[ 243is essentially an alias for the 244.Xr test 1 245command. 246This hard link exists so 247.Xr test 1 248may be invoked from shell scripts, for example, using the 249.Li "if [ ]" 250construct. 251.Pp 252In the next example, the second call to 253.Nm 254removes the original 255.Pa foo 256and creates a replacement pointing to 257.Pa baz : 258.Bd -literal -offset indent 259# mkdir bar baz 260# ln -s bar foo 261# ln -shf baz foo 262.Ed 263.Pp 264Without the 265.Fl h 266option, this would instead leave 267.Pa foo 268pointing to 269.Pa bar 270and inside 271.Pa foo 272create a new symlink 273.Pa baz 274pointing to itself. 275This results from directory-walking. 276.Pp 277An easy rule to remember is that the argument order for 278.Nm 279is the same as for 280.Xr cp 1 : 281The first argument needs to exist, the second one is created. 282.Sh COMPATIBILITY 283The 284.Fl h , 285.Fl i , 286.Fl n , 287.Fl v 288and 289.Fl w 290options are non-standard and their use in scripts is not recommended. 291They are provided solely for compatibility with other 292.Nm 293implementations. 294.Pp 295The 296.Fl F 297option is a 298.Fx 299extension and should not be used in portable scripts. 300.Sh SEE ALSO 301.Xr link 2 , 302.Xr lstat 2 , 303.Xr readlink 2 , 304.Xr stat 2 , 305.Xr symlink 2 , 306.Xr symlink 7 307.Sh STANDARDS 308The 309.Nm 310utility conforms to 311.St -p1003.2-92 . 312.Pp 313The simplified 314.Nm link 315command conforms to 316.St -susv2 . 317.Sh HISTORY 318An 319.Nm 320command appeared in 321.At v1 . 322