rtf_send.2

rtlinux(realtime linix)3.0,在kernel2.2.18上编译运行

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.TH RTF_SEND 2 "15 August 1997" "rt_ipc" "rt_ipc"
.SH NAME
rtf_send \- send data to an rt_ipc real-time fifo
.SH SYNOPSIS
.nf
.B #define MODULE
.B #include <linux/module.h> 
.B #include <linux/kernel.h> 
.B #include <linux/version.h> 
.B #include <linux/errno.h> 
.B #include <linux/rtf.h> 
.B #include "rt_ipc.h"
.fi
.sp
.BI "int rtf_send(unsigned int " fifo ", void *" buf ", int " count ", RTIME " timeout ")
.SH DESCRIPTION
.B rtf_send
sends data to the rt-fifo
.IR fifo .
The data, of size
.IR count ,
is taken from
.IR buf .
If
.I timeout
is RT_NO_WAIT, the function returns immediately even if
.I count
bytes cannot be sent.  If
.I timeout
is RT_WAIT_FOREVER, the function blocks until
.I count
bytes can be sent.  If
.I timeout
is any other value, it represents the time at which the function will return
with a timeout after unsuccessfully waiting to send the data.  If
.B rtf_send
cannot send the entire block, no data is sent.
.PP
The rt_ipc RT-FIFO is a mechanism, implemented as a character device, to
communicate between real-time tasks and ordinary Linux processes.  It is
based on the Real-Time Linux RT-FIFO mechanism.  The
rtf_* functions are used by the real-time tasks; Linux processes use
standard character device access functions such as
.BR read(2) ,
.BR write(2) ,
and
.BR select(2) .
.SH "RETURN VALUE"
If the return value is greater than or equal to zero, it represents the
number of bytes received.  This might be zero if the function timed out
or RT_NO_WAIT was specified and less than
.I count
bytes could be sent.  On failure, a negative value is returned
as described below.
.SH ERRORS
.IP \fB-ENODEV\fP
.I fifo
is not less than IPC_RTF_NO and RTF_NO.
.IP \fB-EINVAL\fP
.I fifo
is not a valid fifo identifier.
.SH "AUTHOR"
Jerry Epplin <[e-mail]>
.SH "SEE ALSO"
.BR rtf_ipc_create (2), 
.BR rtf_ipc_destroy (2), 
.BR rtf_receive (2)