Section: POSIX Programmer's Manual (1P)
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
--- make FIFO special files
mkfifo [-m mode] file...
utility shall create the FIFO special files specified by the operands,
in the order specified.
utility shall perform actions equivalent to the
function defined in the System Interfaces volume of POSIX.1-2017, called with the following arguments:
operand is used as the
The value of the bitwise-inclusive OR of S_IRUSR, S_IWUSR, S_IRGRP,
S_IWGRP, S_IROTH, and S_IWOTH is used as the
argument. (If the
option is specified, the value of the
argument is unspecified, but the FIFO shall at no time have permissions
less restrictive than the
utility shall conform to the Base Definitions volume of POSIX.1-2017,
, Utility Syntax Guidelines.
The following option shall be supported:
- -m mode
Set the file permission bits of the newly-created FIFO to the specified
option-argument shall be the same as the
operand defined for the
utility. In the
shall be interpreted relative to an assumed initial mode of
The following operand shall be supported:
A pathname of the FIFO special file to be created.
The following environment variables shall affect the execution of
Provide a default value for the internationalization variables that are
unset or null. (See the Base Definitions volume of POSIX.1-2017,
Section 8.2, Internationalization Variables
for the precedence of internationalization variables used to determine
the values of locale categories.)
If set to a non-empty string value, override the values of all the
other internationalization variables.
Determine the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to
multi-byte characters in arguments).
Determine the locale that should be used to affect the format and
contents of diagnostic messages written to standard error.
Determine the location of message catalogs for the processing of
The standard error shall be used only for diagnostic messages.
The following exit values shall be returned:
All the specified FIFO special files were created successfully.
An error occurred.
CONSEQUENCES OF ERRORS
The following sections are informative.
This utility was added to permit shell applications to create FIFO
option was added to control the file mode, for consistency with the
similar functionality provided by the
Early proposals included a
option similar to the
option that created intermediate directories leading up to the FIFO
specified by the final component. This was removed because it is not
commonly needed and is not common practice with similar utilities.
The functionality of
is described substantially through a reference to the
function in the System Interfaces volume of POSIX.1-2017. For example, by default, the mode of the FIFO
file is affected by the file mode creation mask in accordance with the
specified behavior of the
function. In this way, there is less duplication of effort required for
describing details of the file creation.
The Base Definitions volume of POSIX.1-2017,
Chapter 8, Environment Variables,
Section 12.2, Utility Syntax Guidelines
The System Interfaces volume of POSIX.1-2017,
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version 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
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