1.\" $NetBSD: unlink.2,v 1.20 2004/05/13 10:20:58 wiz Exp $ 2.\" 3.\" Copyright (c) 1980, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)unlink.2 8.1 (Berkeley) 6/4/93 31.\" 32.Dd June 4, 1993 33.Dt UNLINK 2 34.Os 35.Sh NAME 36.Nm unlink 37.Nd remove directory entry 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In unistd.h 42.Ft int 43.Fn unlink "const char *path" 44.Sh DESCRIPTION 45The 46.Fn unlink 47function 48removes the link named by 49.Fa path 50from its directory and decrements the link count of the 51file which was referenced by the link. 52If that decrement reduces the link count of the file 53to zero, 54and no process has the file open, then 55all resources associated with the file are reclaimed. 56If one or more process have the file open when the last link is removed, 57the link is removed, but the removal of the file is delayed until 58all references to it have been closed. 59.Sh RETURN VALUES 60Upon successful completion, a value of 0 is returned. 61Otherwise, a value of \-1 is returned and 62.Va errno 63is set to indicate the error. 64.Sh ERRORS 65The 66.Fn unlink 67succeeds unless: 68.Bl -tag -width Er 69.It Bq Er ENOTDIR 70A component of the path prefix is not a directory. 71.It Bq Er ENAMETOOLONG 72A component of a pathname exceeded 73.Dv {NAME_MAX} 74characters, or an entire path name exceeded 75.Dv {PATH_MAX} 76characters. 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, or 81write permission is denied on the directory containing the link 82to be removed. 83.It Bq Er ELOOP 84Too many symbolic links were encountered in translating the pathname. 85.It Bq Er EPERM 86The named file is a directory and the effective user ID 87of the process is not the super-user, the file system 88containing the file does not permit the use of 89.Fn unlink 90on a directory, 91or the directory containing the file is marked sticky, 92and neither the containing directory nor the file to be removed 93are owned by the effective user ID. 94.It Bq Er EBUSY 95The entry to be unlinked is the mount point for a 96mounted file system. 97.It Bq Er EIO 98An I/O error occurred while deleting the directory entry 99or deallocating the inode. 100.It Bq Er EROFS 101The named file resides on a read-only file system. 102.It Bq Er EFAULT 103.Fa path 104points outside the process's allocated address space. 105.El 106.Sh SEE ALSO 107.Xr close 2 , 108.Xr link 2 , 109.Xr rmdir 2 , 110.Xr symlink 7 111.Sh STANDARDS 112The 113.Fn unlink 114function conforms to 115.St -p1003.1-90 . 116.Sh HISTORY 117An 118.Fn unlink 119function call appeared in 120.At v6 . 121