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.\" @(#)unlink.2 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD: src/lib/libc/sys/unlink.2,v 1.8.2.4 2001/12/14 18:34:02 ru Exp $ 34.\" $DragonFly: src/lib/libc/sys/unlink.2,v 1.4 2007/04/26 17:35:03 swildner Exp $ 35.\" 36.Dd June 4, 1993 37.Dt UNLINK 2 38.Os 39.Sh NAME 40.Nm unlink 41.Nd remove directory entry 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In unistd.h 46.Ft int 47.Fn unlink "const char *path" 48.Sh DESCRIPTION 49The 50.Fn unlink 51function 52removes the link named by 53.Fa path 54from its directory and decrements the link count of the 55file which was referenced by the link. 56If that decrement reduces the link count of the file 57to zero, 58and no process has the file open, then 59all resources associated with the file are reclaimed. 60If one or more process have the file open when the last link is removed, 61the link is removed, but the removal of the file is delayed until 62all references to it have been closed. 63.Fa path 64may not be a directory. 65.Sh RETURN VALUES 66.Rv -std unlink 67.Sh ERRORS 68The 69.Fn unlink 70succeeds unless: 71.Bl -tag -width Er 72.It Bq Er ENOTDIR 73A component of the path prefix is not a directory. 74.It Bq Er ENAMETOOLONG 75A component of a pathname exceeded 255 characters, 76or an entire path name exceeded 1023 characters. 77.It Bq Er ENOENT 78The named file does not exist. 79.It Bq Er EACCES 80Search permission is denied for a component of the path prefix. 81.It Bq Er EACCES 82Write permission is denied on the directory containing the link 83to be removed. 84.It Bq Er ELOOP 85Too many symbolic links were encountered in translating the pathname. 86.It Bq Er EPERM 87The named file has its immutable or append-only flag set (see 88.Xr chflags 2 ) . 89.It Bq Er EPERM 90The named file is a directory. 91.It Bq Er EPERM 92The directory containing the file is marked sticky, 93and neither the containing directory nor the file to be removed 94are owned by the effective user ID. 95.It Bq Er EBUSY 96The entry to be unlinked is the mount point for a 97mounted file system. 98.It Bq Er EIO 99An I/O error occurred while deleting the directory entry 100or deallocating the inode. 101.It Bq Er EROFS 102The named file resides on a read-only file system. 103.It Bq Er EFAULT 104.Fa Path 105points outside the process's allocated address space. 106.El 107.Sh SEE ALSO 108.Xr close 2 , 109.Xr link 2 , 110.Xr rmdir 2 , 111.Xr symlink 7 112.Sh HISTORY 113An 114.Fn unlink 115function call appeared in 116.At v6 . 117.Pp 118The 119.Fn unlink 120system call traditionally allows the super-user to unlink directories which 121can damage the filesystem integrity. This implementation no longer permits 122it. 123