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<HTML
><HEAD
><TITLE
>rtf_create</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.64
"></HEAD
><BODY
CLASS="REFENTRY"
><H1
><A
NAME="AEN1"
>rtf_create</A
></H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN5"
></A
><H2
>Name</H2
>rtf_create -- create a realtime fifo</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN8"
></A
><H2
>Synopsis</H2
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="SYNOPSIS"
> #include <rtl_fifo.h>
int <TT
CLASS="FUNCTION"
>rtf_create</TT
>(unsigned int <TT
CLASS="PARAMETER"
><I
>fifo</I
></TT
>, int <TT
CLASS="PARAMETER"
><I
>size</I
></TT
>);</PRE
></TD
></TR
></TABLE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN13"
></A
><H2
>DESCRIPTION</H2
><P
><TT
CLASS="FUNCTION"
>rtf_create</TT
> creates a realtime fifo (RT-FIFO) of size <TT
CLASS="PARAMETER"
><I
>size</I
></TT
> and assigns it the identifier <TT
CLASS="PARAMETER"
><I
>fifo</I
></TT
>. <TT
CLASS="PARAMETER"
><I
>fifo</I
></TT
> is a value unique within the system, and must be less than RTF_NO.</P
><P
>The RT-FIFO is a mechanism, implemented as a character device, to communicate between realtime tasks and ordinary Linux processes. The rtf_* functions are used by the realtime tasks; Linux processes use standard character device access functions such as <TT
CLASS="FUNCTION"
>read(3)</TT
>, <TT
CLASS="FUNCTION"
>write(3)</TT
>, and <TT
CLASS="FUNCTION"
>select(3)</TT
>.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN24"
></A
><H2
>RETURN VALUE</H2
><P
>On success, 0 is returned. On failure, a negative value is returned as described below.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN27"
></A
><H2
>ERRORS</H2
><P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
>-ENODEV</DT
><DD
><P
><TT
CLASS="PARAMETER"
><I
>fifo</I
></TT
> is greater than or equal to RTF_NO.</P
></DD
><DT
>-EBUSY</DT
><DD
><P
><TT
CLASS="PARAMETER"
><I
>fifo</I
></TT
> is already in use. Choose a different ID.</P
></DD
><DT
>-ENOMEM</DT
><DD
><P
><TT
CLASS="PARAMETER"
><I
>size</I
></TT
> bytes could not be allocated for the RT-FIFO.</P
></DD
></DL
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN45"
></A
><H2
>NOTES</H2
><P
>This function should only be used in the Linux <TT
CLASS="FUNCTION"
>init_module()</TT
> context or in user space via PSC library (please see below).
RT-FIFOs created in <TT
CLASS="FUNCTION"
>init_module()</TT
> should be destroyed with <TT
CLASS="FUNCTION"
>rtf_destroy()</TT
> in <TT
CLASS="FUNCTION"
>cleanup_module</TT
>.</P
><P
><TT
CLASS="FUNCTION"
>rtf_create</TT
> is a system call made available by PSC,
the user-level real-time signal library. It can be called from user space,
but not from PSC handlers.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN54"
></A
><H2
>SEE ALSO</H2
><A
HREF="rtf_create_handler.3.html"
TARGET="_top"
>rtf_create_handler(3)</A
>, <A
HREF="rtf_destroy.3.html"
TARGET="_top"
>rtf_destroy(3)</A
>, <A
HREF="rtf_get.3.html"
TARGET="_top"
>rtf_get(3)</A
>, <A
HREF="rtf_put.3.html"
TARGET="_top"
>rtf_put(3)</A
><P
>1997 Jerry Epplin.</P
><P
>Modifications for RTLinux 2.x and 3.x by Michael Barabanov. 2001 FSMLabs Inc.</P
><P
>All rights reserved.</P
></DIV
></BODY
></HTML
>
|
