mkfifo — make a FIFO special file (a named pipe)
#include <sys/types.h> #include <sys/stat.h>
int
mkfifo( |
const char *pathname, |
mode_t mode); |
mkfifo() makes a FIFO
special file with name pathname. mode specifies the FIFO's
permissions. It is modified by the process's umask in the usual way: the permissions of
the created file are (mode & ~umask).
A FIFO special file is similar to a pipe, except that it
is created in a different way. Instead of being an anonymous
communications channel, a FIFO special file is entered into
the file system by calling mkfifo().
Once you have created a FIFO special file in this way, any process can open it for reading or writing, in the same way as an ordinary file. However, it has to be open at both ends simultaneously before you can proceed to do any input or output operations on it. Opening a FIFO for reading normally blocks until some other process opens the same FIFO for writing, and vice versa. See fifo(7) for nonblocking handling of FIFO special files.
On success mkfifo() returns
0. In the case of an error, −1 is returned (in which
case, errno is set
appropriately).
One of the directories in pathname did not allow
search (execute) permission.
pathname
already exists. This includes the case where pathname is a symbolic
link, dangling or not.
Either the total length of pathname is greater than
PATH_MAX, or an
individual filename component has a length greater than
NAME_MAX. In the GNU
system, there is no imposed limit on overall filename
length, but some file systems may place limits on the
length of a component.
A directory component in pathname does not exist
or is a dangling symbolic link.
The directory or file system has no room for the new file.
A component used as a directory in pathname is not, in fact,
a directory.
pathname
refers to a read-only file system.
This page is part of release 3.33 of the Linux man-pages project. A
description of the project, and information about reporting
bugs, can be found at http://man7.org/linux/man-pages/.
|
This manpage is Copyright (C) 1995 James R. Van Zandt <jrvvanzandt.mv.com> Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linux kernel and libraries are constantly changing, this manual page may be incorrect or out-of-date. The author(s) assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The author(s) may not have taken the same level of care in the production of this manual, which is licensed free of charge, as they might when working professionally. Formatted or processed versions of this manual, if unaccompanied by the source, must acknowledge the copyright and authors of this work. changed section from 2 to 3, aeb, 950919 |