1.\" $NetBSD: unlink.2,v 1.16 2002/02/08 01:28:23 ross 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. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)unlink.2 8.1 (Berkeley) 6/4/93 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.Fd #include \*[Lt]unistd.h\*[Gt] 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.Sh RETURN VALUES 64Upon successful completion, a value of 0 is returned. 65Otherwise, a value of -1 is returned and 66.Va errno 67is set to indicate the error. 68.Sh ERRORS 69The 70.Fn unlink 71succeeds unless: 72.Bl -tag -width Er 73.It Bq Er ENOTDIR 74A component of the path prefix is not a directory. 75.It Bq Er ENAMETOOLONG 76A component of a pathname exceeded 77.Dv {NAME_MAX} 78characters, or an entire path name exceeded 79.Dv {PATH_MAX} 80characters. 81.It Bq Er ENOENT 82The named file does not exist. 83.It Bq Er EACCES 84Search permission is denied for a component of the path prefix, or 85write permission is denied on the directory containing the link 86to be removed. 87.It Bq Er ELOOP 88Too many symbolic links were encountered in translating the pathname. 89.It Bq Er EPERM 90The named file is a directory and the effective user ID 91of the process is not the super-user, the file system 92containing the file does not permit the use of 93.Fn unlink 94on a directory, 95or the 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 EBUSY 99The entry to be unlinked is the mount point for a 100mounted file system. 101.It Bq Er EIO 102An I/O error occurred while deleting the directory entry 103or deallocating the inode. 104.It Bq Er EROFS 105The named file resides on a read-only file system. 106.It Bq Er EFAULT 107.Fa path 108points outside the process's allocated address space. 109.El 110.Sh SEE ALSO 111.Xr close 2 , 112.Xr link 2 , 113.Xr rmdir 2 , 114.Xr symlink 7 115.Sh STANDARDS 116The 117.Fn unlink 118function conforms to 119.St -p1003.1-90 . 120.Sh HISTORY 121An 122.Fn unlink 123function call appeared in 124.At v6 . 125