PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

MKFIFO(1P)                POSIX Programmer's Manual               MKFIFO(1P)

PROLOG         top

       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.

NAME         top

       mkfifo — make FIFO special files

SYNOPSIS         top

       mkfifo [−m mode] file...

DESCRIPTION         top

       The mkfifo utility shall create the FIFO special files specified by
       the operands, in the order specified.

       For each file operand, the mkfifo utility shall perform actions
       equivalent to the mkfifo() function defined in the System Interfaces
       volume of POSIX.1‐2008, called with the following arguments:

        1. The file operand is used as the path argument.

        2. 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 mode
           argument. (If the −m option is specified, the value of the
           mkfifo() mode argument is unspecified, but the FIFO shall at no
           time have permissions less restrictive than the −m mode option-
           argument.)

OPTIONS         top

       The mkfifo utility shall conform to the Base Definitions volume of
       POSIX.1‐2008, Section 12.2, Utility Syntax Guidelines.

       The following option shall be supported:

       −m mode   Set the file permission bits of the newly-created FIFO to
                 the specified mode value. The mode option-argument shall be
                 the same as the mode operand defined for the chmod utility.
                 In the symbolic_mode strings, the op characters '+' and '−'
                 shall be interpreted relative to an assumed initial mode of
                 a=rw.

OPERANDS         top

       The following operand shall be supported:

       file      A pathname of the FIFO special file to be created.

STDIN         top

       Not used.

INPUT FILES         top

       None.

ENVIRONMENT VARIABLES         top

       The following environment variables shall affect the execution of
       mkfifo:

       LANG      Provide a default value for the internationalization
                 variables that are unset or null. (See the Base Definitions
                 volume of POSIX.1‐2008, Section 8.2, Internationalization
                 Variables for the precedence of internationalization
                 variables used to determine the values of locale
                 categories.)

       LC_ALL    If set to a non-empty string value, override the values of
                 all the other internationalization variables.

       LC_CTYPE  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).

       LC_MESSAGES
                 Determine the locale that should be used to affect the
                 format and contents of diagnostic messages written to
                 standard error.

       NLSPATH   Determine the location of message catalogs for the
                 processing of LC_MESSAGES.

ASYNCHRONOUS EVENTS         top

       Default.

STDOUT         top

       Not used.

STDERR         top

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES         top

       None.

EXTENDED DESCRIPTION         top

       None.

EXIT STATUS         top

       The following exit values shall be returned:

        0    All the specified FIFO special files were created successfully.

       >0    An error occurred.

CONSEQUENCES OF ERRORS         top

       Default.

       The following sections are informative.

APPLICATION USAGE         top

       None.

EXAMPLES         top

       None.

RATIONALE         top

       This utility was added to permit shell applications to create FIFO
       special files.

       The −m option was added to control the file mode, for consistency
       with the similar functionality provided by the mkdir utility.

       Early proposals included a −p option similar to the mkdir −p 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 mkfifo is described substantially through a
       reference to the mkfifo() function in the System Interfaces volume of
       POSIX.1‐2008. 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 mkfifo() function. In this way, there is
       less duplication of effort required for describing details of the
       file creation.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       chmod(1p), umask(1p)

       The Base Definitions volume of POSIX.1‐2008, Chapter 8, Environment
       Variables, Section 12.2, Utility Syntax Guidelines

       The System Interfaces volume of POSIX.1‐2008, mkfifo(3p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) 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 http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                          MKFIFO(1P)