1.\" $OpenBSD: unlink.2,v 1.12 2002/01/24 21:18:36 mickey Exp $ 2.\" $NetBSD: unlink.2,v 1.7 1995/02/27 12:39:13 cgd Exp $ 3.\" 4.\" Copyright (c) 1980, 1991, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. All advertising materials mentioning features or use of this software 16.\" must display the following acknowledgement: 17.\" This product includes software developed by the University of 18.\" California, Berkeley and its contributors. 19.\" 4. Neither the name of the University nor the names of its contributors 20.\" may be used to endorse or promote products derived from this software 21.\" without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" @(#)unlink.2 8.1 (Berkeley) 6/4/93 36.\" 37.Dd June 4, 1993 38.Dt UNLINK 2 39.Os 40.Sh NAME 41.Nm unlink 42.Nd remove directory entry 43.Sh SYNOPSIS 44.Fd #include <unistd.h> 45.Ft int 46.Fn unlink "const char *path" 47.Sh DESCRIPTION 48The 49.Fn unlink 50function removes the link named by 51.Fa path 52from its directory and decrements the link count of the 53file which was referenced by the link. 54If that decrement reduces the link count of the file 55to zero, 56and no process has the file open, then 57all resources associated with the file are reclaimed. 58If one or more process have the file open when the last link is removed, 59the link is removed, but the removal of the file is delayed until 60all references to it have been closed. 61.Sh RETURN VALUES 62Upon successful completion, a value of 0 is returned. 63Otherwise, a value of \-1 is returned and 64.Va errno 65is set to indicate the error. 66.Sh ERRORS 67The 68.Fn unlink 69succeeds unless: 70.Bl -tag -width Er 71.It Bq Er ENOTDIR 72A component of the path prefix is not a directory. 73.It Bq Er ENAMETOOLONG 74A component of a pathname exceeded 75.Dv {NAME_MAX} 76characters, or an entire path name exceeded 77.Dv {PATH_MAX} 78characters. 79.It Bq Er ENOENT 80The named file does not exist. 81.It Bq Er EACCES 82Search permission is denied for a component of the path prefix. 83.It Bq Er EACCES 84Write permission is denied on the directory containing the link 85to be removed. 86.It Bq Er ELOOP 87Too many symbolic links were encountered in translating the pathname. 88.It Bq Er EPERM 89The named file is a directory and the effective user ID 90of the process is not the superuser, or the file system 91containing the file does not permit the use of 92.Fn unlink 93on a directory. 94.It Bq Er EPERM 95The directory containing the file is marked sticky, 96and neither the containing directory nor the file to be removed 97are owned by the effective user ID. 98.It Bq Er EPERM 99The named file has its immutable or append-only flag set (see 100.Xr chflags 2 ) . 101.It Bq Er EBUSY 102The entry to be unlinked is the mount point for a 103mounted file system. 104.It Bq Er EIO 105An I/O error occurred while deleting the directory entry 106or deallocating the inode. 107.It Bq Er EROFS 108The named file resides on a read-only file system. 109.It Bq Er EFAULT 110.Fa path 111points outside the process's allocated address space. 112.El 113.Sh SEE ALSO 114.Xr close 2 , 115.Xr link 2 , 116.Xr rmdir 2 , 117.Xr symlink 7 118.Sh HISTORY 119An 120.Fn unlink 121function call appeared in 122.At v2 . 123