84d9c625bf
- Fix for possible unset uid/gid in toproto
- Fix for default mtree style
- Update libelf
- Importing libexecinfo
- Resynchronize GCC, mpc, gmp, mpfr
- build.sh: Replace params with show-params.
This has been done as the make target has been renamed in the same
way, while a new target named params has been added. This new
target generates a file containing all the parameters, instead of
printing it on the console.
- Update test48 with new etc/services (Fix by Ben Gras <ben@minix3.org)
get getservbyport() out of the inner loop
Change-Id: Ie6ad5226fa2621ff9f0dee8782ea48f9443d2091
192 lines
5.2 KiB
Groff
192 lines
5.2 KiB
Groff
.\" $NetBSD: unlink.2,v 1.28 2013/07/28 13:53:04 njoly Exp $
|
|
.\"
|
|
.\" Copyright (c) 1980, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)unlink.2 8.1 (Berkeley) 6/4/93
|
|
.\"
|
|
.Dd July 28, 2013
|
|
.Dt UNLINK 2
|
|
.Os
|
|
.Sh NAME
|
|
.Nm unlink ,
|
|
.Nm unlinkat ,
|
|
.Nd remove directory entry
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In unistd.h
|
|
.Ft int
|
|
.Fn unlink "const char *path"
|
|
.In fcntl.h
|
|
.Ft int
|
|
.Fn unlinkat "int fd" "const char *path" "int flag"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn unlink
|
|
function
|
|
removes the link named by
|
|
.Fa path
|
|
from its directory and decrements the link count of the
|
|
file which was referenced by the link.
|
|
If that decrement reduces the link count of the file
|
|
to zero,
|
|
and no process has the file open, then
|
|
all resources associated with the file are reclaimed.
|
|
If one or more process have the file open when the last link is removed,
|
|
the link is removed, but the removal of the file is delayed until
|
|
all references to it have been closed.
|
|
.Pp
|
|
.Fn unlinkat
|
|
works the same way as
|
|
.Fn unlink
|
|
except if
|
|
.Fa path
|
|
is relative.
|
|
In that case, it is looked up from a directory whose file
|
|
descriptor was passed as
|
|
.Fa fd .
|
|
Search permission is required on this directory.
|
|
.\" (These alternatives await a decision about the semantics of O_SEARCH)
|
|
.\" Search permission is required on this directory
|
|
.\" except if
|
|
.\" .Fa fd
|
|
.\" was opened with the
|
|
.\" .Dv O_SEARCH
|
|
.\" flag.
|
|
.\" - or -
|
|
.\" This file descriptor must have been opened with the
|
|
.\" .Dv O_SEARCH
|
|
.\" flag.
|
|
.Fa fd
|
|
can be set to
|
|
.Dv AT_FDCWD
|
|
in order to specify the current directory.
|
|
.Pp
|
|
.Fn unlinkat
|
|
will remove directories just like
|
|
.Fn rmdir
|
|
provided
|
|
.Dv AT_REMOVEDIR
|
|
is set in
|
|
.Fa flag .
|
|
.Sh RETURN VALUES
|
|
.Rv -std unlink unlinkat
|
|
.Sh ERRORS
|
|
The
|
|
.Fn unlink
|
|
and
|
|
.Fn unlinkat
|
|
succeeds unless:
|
|
.Bl -tag -width Er
|
|
.It Bq Er EACCES
|
|
Search permission is denied for a component of the path prefix, or
|
|
write permission is denied on the directory containing the link
|
|
to be removed.
|
|
.It Bq Er EBUSY
|
|
The entry to be unlinked is the mount point for a
|
|
mounted file system.
|
|
.It Bq Er EFAULT
|
|
.Fa path
|
|
points outside the process's allocated address space.
|
|
.It Bq Er EIO
|
|
An I/O error occurred while deleting the directory entry
|
|
or deallocating the inode.
|
|
.It Bq Er ELOOP
|
|
Too many symbolic links were encountered in translating the pathname.
|
|
.It Bq Er ENAMETOOLONG
|
|
A component of a pathname exceeded
|
|
.Brq Dv NAME_MAX
|
|
characters, or an entire path name exceeded
|
|
.Brq Dv PATH_MAX
|
|
characters.
|
|
.It Bq Er ENOENT
|
|
The named file does not exist.
|
|
.It Bq Er ENOTDIR
|
|
A component of the path prefix is not a directory.
|
|
.It Bq Er EPERM
|
|
The named file is a directory and the effective user ID
|
|
of the process is not the super-user, the file system
|
|
containing the file does not permit the use of
|
|
.Fn unlink
|
|
on a directory,
|
|
or the directory containing the file is marked sticky,
|
|
and neither the containing directory nor the file to be removed
|
|
are owned by the effective user ID.
|
|
.It Bq Er EROFS
|
|
The named file resides on a read-only file system.
|
|
.El
|
|
.Pp
|
|
In addition,
|
|
.Fn unlinkat
|
|
will fail if:
|
|
.Bl -tag -width Er
|
|
.It Bq Er EBADF
|
|
.Fa path
|
|
does not specify an absolute path and
|
|
.Fa fd
|
|
is neither
|
|
.Dv AT_FDCWD
|
|
nor a valid file descriptor open for reading or searching.
|
|
.It Bq Er ENOTDIR
|
|
.Fa path
|
|
is not an absolute path and
|
|
.Fa fd
|
|
is a file descriptor associated with a non-directory file; or
|
|
.Fa flag
|
|
has
|
|
.Dv AT_REMOVEDIR
|
|
set and
|
|
.Fa path
|
|
does not name a directory.
|
|
.It Bq Er ENOTEMPTY
|
|
.Fa flag
|
|
has
|
|
.Dv AT_REMOVEDIR
|
|
set and
|
|
.Fa path
|
|
is a directory that is not empty.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr close 2 ,
|
|
.Xr link 2 ,
|
|
.Xr rmdir 2 ,
|
|
.Xr symlink 7
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn unlink
|
|
function conforms to
|
|
.St -p1003.1-90 .
|
|
.Fn unlinkat
|
|
conforms to
|
|
.St -p1003.1-2008 .
|
|
.Sh HISTORY
|
|
An
|
|
.Fn unlink
|
|
function call appeared in
|
|
.At v2 .
|