1.\" Copyright (c) 1980, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. 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.\" @(#)link.2 8.3 (Berkeley) 1/12/94 33.\" $FreeBSD: src/lib/libc/sys/link.2,v 1.11.2.7 2001/12/14 18:34:01 ru Exp $ 34.\" 35.Dd March 5, 1999 36.Dt LINK 2 37.Os 38.Sh NAME 39.Nm link 40.Nd make a hard file link 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In unistd.h 45.Ft int 46.Fn link "const char *name1" "const char *name2" 47.Sh DESCRIPTION 48The 49.Fn link 50function call 51atomically creates the specified directory entry (hard link) 52.Fa name2 53with the attributes of the underlying object pointed at by 54.Fa name1 . 55If the link is successful: the link count of the underlying object 56is incremented; 57.Fa name1 58and 59.Fa name2 60share equal access and rights 61to the 62underlying object. 63.Pp 64If 65.Fa name1 66is removed, the file 67.Fa name2 68is not deleted and the link count of the 69underlying object is 70decremented. 71.Pp 72.Fa Name1 73must exist for the hard link to 74succeed and 75both 76.Fa name1 77and 78.Fa name2 79must be in the same file system. 80.Fa name1 81may not be a directory. 82.Sh RETURN VALUES 83.Rv -std link 84.Sh ERRORS 85.Fn Link 86will fail and no link will be created if: 87.Bl -tag -width Er 88.It Bq Er ENOTDIR 89A component of either path prefix is not a directory. 90.It Bq Er ENAMETOOLONG 91A component of either pathname exceeded 255 characters, 92or entire length of either path name exceeded 1023 characters. 93.It Bq Er ENOENT 94A component of either path prefix does not exist. 95.It Bq Er EOPNOTSUPP 96The file system containing the file named by 97.Fa name1 98does not support links. 99.It Bq Er EMLINK 100The link count of the file named by 101.Fa name1 102would exceed 32767. 103.It Bq Er EACCES 104A component of either path prefix denies search permission. 105.It Bq Er EACCES 106The requested link requires writing in a directory with a mode 107that denies write permission. 108.It Bq Er ELOOP 109Too many symbolic links were encountered in translating one of the pathnames. 110.It Bq Er ENOENT 111The file named by 112.Fa name1 113does not exist. 114.It Bq Er EEXIST 115The link named by 116.Fa name2 117does exist. 118.It Bq Er EPERM 119The file named by 120.Fa name1 121is a directory. 122.It Bq Er EXDEV 123The link named by 124.Fa name2 125and the file named by 126.Fa name1 127are on different file systems. 128.It Bq Er ENOSPC 129The directory in which the entry for the new link is being placed 130cannot be extended because there is no space left on the file 131system containing the directory. 132.It Bq Er EDQUOT 133The directory in which the entry for the new link 134is being placed cannot be extended because the 135user's quota of disk blocks on the file system 136containing the directory has been exhausted. 137.It Bq Er EIO 138An I/O error occurred while reading from or writing to 139the file system to make the directory entry. 140.It Bq Er EROFS 141The requested link requires writing in a directory on a read-only file 142system. 143.It Bq Er EFAULT 144One of the pathnames specified 145is outside the process's allocated address space. 146.El 147.Sh SEE ALSO 148.Xr readlink 2 , 149.Xr symlink 2 , 150.Xr unlink 2 151.Sh STANDARDS 152The 153.Fn link 154function call is expected to conform to 155.St -p1003.1-90 . 156.Sh HISTORY 157A 158.Fn link 159function call appeared in 160.At v7 . 161.Pp 162The 163.Fn link 164system call traditionally allows the super-user to link directories which 165corrupts the filesystem coherency. This implementation no longer permits 166it. 167