xref: /illumos-gate/usr/src/man/man3c/mkfifo.3c (revision 4f364e7c95ee7fd9d5bbeddc1940e92405bb0e72)
te
Copyright (c) 2002, Sun Microsystems, Inc. All Rights Reserved.
Copyright 1989 AT&T
Portions Copyright (c) 2001, the Institute of Electrical and Electronics Engineers, Inc. and The Open Group. All Rights Reserved.
Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.
The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
This notice shall appear on any product containing this material.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
MKFIFO 3C "Apr 24, 2002"
NAME
mkfifo - make a FIFO special file
SYNOPSIS

#include <sys/types.h>
#include <sys/stat.h>

int mkfifo(const char *path, mode_t mode);
DESCRIPTION

The mkfifo() function creates a new FIFO special file named by the pathname pointed to by path. The file permission bits of the new FIFO are initialized from mode. The file permission bits of the mode argument are modified by the process's file creation mask (see umask(2)). Bits other than the file permission bits in mode are ignored.

If path names a symbolic link, mkfifo() fails and sets errno to EEXIST.

The FIFO's user ID is set to the process's effective user ID. The FIFO's group ID is set to the group ID of the parent directory or to the effective group ID of the process.

The mkfifo() function calls mknod(2) to create the file.

Upon successful completion, mkfifo() marks for update the st_atime, st_ctime, and st_mtime fields of the file. Also, the st_ctime and st_mtime fields of the directory that contains the new entry are marked for update.

RETURN VALUES

Upon successful completion, 0 is returned. Otherwise, -1 is returned and errno is set to indicate the error.

ERRORS

The mkfifo() function will fail if: EACCES

A component of the path prefix denies search permission, or write permission is denied on the parent directory of the FIFO to be created.

EEXIST

The named file already exists.

ELOOP

A loop exists in symbolic links encountered during resolution of the path argument.

ENAMETOOLONG

The length of the path argument exceeds {PATH_MAX} or a pathname component is longer than {NAME_MAX}.

ENOENT

A component of the path prefix specified by path does not name an existing directory or path is an empty string.

ENOSPC

The directory that would contain the new file cannot be extended or the file system is out of file-allocation resources.

ENOTDIR

A component of the path prefix is not a directory.

EROFS

The named file resides on a read-only file system.

The mkfifo() function may fail if: ELOOP

Too many symbolic links were encountered in resolving path.

ENAMETOOLONG

The length of the path argument exceeds {PATH_MAX} or a pathname component is longer than {NAME_MAX}.

EXAMPLES

Example 1 Create a FIFO File

The following example demonstrates how to create a FIFO file named /home/cnd/mod_done with read and write permissions for the owner and read permissions for the group and others.

#include sys/types.h>
#include sys/stat.h>
int status;
...
status = mkfifo("/home/cnd/mod_done", S_IWUSR | S_IRUSR |
 S_IRGRP | S_IROTH);
ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Standard
MT-Level MT-Safe
SEE ALSO

mkdir(1), chmod(2), exec(2), mknod(2), umask(2), stat.h(3HEAD), ufs(7FS), attributes(5), standards(5)