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



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.


NNAAMMEE
       mkfifo -- make FIFO special files

SSYYNNOOPPSSIISS
       mkfifo [[-m _m_o_d_e]] _f_i_l_e...

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

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

        1. The _f_i_l_e operand is used as the _p_a_t_h 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 _m_o_d_e argument. (If the
           --mm option is specified, the value of the _m_k_f_i_f_o() _m_o_d_e argument is
           unspecified, but the FIFO shall at no time have permissions less
           restrictive than the --mm _m_o_d_e option-argument.)

OOPPTTIIOONNSS
       The _m_k_f_i_f_o utility shall conform to the Base Definitions volume of
       POSIX.1-2008, _S_e_c_t_i_o_n _1_2_._2, _U_t_i_l_i_t_y _S_y_n_t_a_x _G_u_i_d_e_l_i_n_e_s.

       The following option shall be supported:

       --mm _m_o_d_e   Set the file permission bits of the newly-created FIFO to the
                 specified _m_o_d_e value. The _m_o_d_e option-argument shall be the
                 same as the _m_o_d_e operand defined for the _c_h_m_o_d utility. In
                 the _s_y_m_b_o_l_i_c___m_o_d_e strings, the _o_p characters ''++'' and ''--''
                 shall be interpreted relative to an assumed initial mode of
                 _a=_r_w.

OOPPEERRAANNDDSS
       The following operand shall be supported:

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

SSTTDDIINN
       Not used.

IINNPPUUTT FFIILLEESS
       None.

EENNVVIIRROONNMMEENNTT VVAARRIIAABBLLEESS
       The following environment variables shall affect the execution of
       _m_k_f_i_f_o:

       _L_A_N_G      Provide a default value for the internationalization
                 variables that are unset or null. (See the Base Definitions
                 volume of POSIX.1-2008, _S_e_c_t_i_o_n _8_._2, _I_n_t_e_r_n_a_t_i_o_n_a_l_i_z_a_t_i_o_n
                 _V_a_r_i_a_b_l_e_s for the precedence of internationalization
                 variables used to determine the values of locale categories.)

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

       _L_C___C_T_Y_P_E  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).

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

       _N_L_S_P_A_T_H   Determine the location of message catalogs for the processing
                 of _L_C___M_E_S_S_A_G_E_S.

AASSYYNNCCHHRROONNOOUUSS EEVVEENNTTSS
       Default.

SSTTDDOOUUTT
       Not used.

SSTTDDEERRRR
       The standard error shall be used only for diagnostic messages.

OOUUTTPPUUTT FFIILLEESS
       None.

EEXXTTEENNDDEEDD DDEESSCCRRIIPPTTIIOONN
       None.

EEXXIITT SSTTAATTUUSS
       The following exit values shall be returned:

        0    All the specified FIFO special files were created successfully.

       >0    An error occurred.

CCOONNSSEEQQUUEENNCCEESS OOFF EERRRROORRSS
       Default.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       None.

EEXXAAMMPPLLEESS
       None.

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

       The --mm option was added to control the file mode, for consistency with
       the similar functionality provided by the _m_k_d_i_r utility.

       Early proposals included a --pp option similar to the _m_k_d_i_r --pp 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 _m_k_f_i_f_o is described substantially through a
       reference to the _m_k_f_i_f_o() 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 _m_k_f_i_f_o() function. In this way, there is less
       duplication of effort required for describing details of the file
       creation.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _c_h_m_o_d, _u_m_a_s_k

       The Base Definitions volume of POSIX.1-2008, _C_h_a_p_t_e_r _8, _E_n_v_i_r_o_n_m_e_n_t
       _V_a_r_i_a_b_l_e_s, _S_e_c_t_i_o_n _1_2_._2, _U_t_i_l_i_t_y _S_y_n_t_a_x _G_u_i_d_e_l_i_n_e_s

       The System Interfaces volume of POSIX.1-2008, _m_k_f_i_f_o()

CCOOPPYYRRIIGGHHTT
       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(1)
