.\".\" Copyright (C) 1997 Jerry Epplin.  All rights reserved..\".\" Permission is granted to make and distribute verbatim copies of this.\" manual provided the copyright notice and this permission notice are.\" preserved on all copies..\".\" Permission is granted to copy and distribute modified versions of this.\" manual under the conditions for verbatim copying, provided that the.\" entire resulting derived work is distributed under the terms of a.\" permission notice identical to this one.\" .\" The author assumes no responsibility for errors or omissions, or for.\" damages resulting from the use of the information contained herein..\" .\" Formatted or processed versions of this manual, if unaccompanied by.\" the source, must acknowledge the copyright and authors of this work..\".TH RTF_RECEIVE 2 "15 August 1997" "rt_ipc" "rt_ipc".SH NAMErtf_receive \- get data from 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_receive(unsigned int " fifo ", void *" buf ", int " count ", RTIME " timeout ").SH DESCRIPTION.B rtf_receivegets data from the rt-fifo.IR fifo .The data, up to size.IR count ,is put into.IR buf .If.I timeoutis RT_NO_WAIT, the function returns immediately even if.I countbytes are not available.  If.I timeoutis RT_WAIT_FOREVER, the function blocks until.I countbytes are available.  If.I timeoutis any other value, it represents the time at which the function will returnwith a timeout after unsuccessfully waiting for data.  In any case, asmany bytes as possible are returned, even if a timeout occurs orRT_NO_WAIT is specified..PPThe rt_ipc RT-FIFO is a mechanism, implemented as a character device, tocommunicate between real-time tasks and ordinary Linux processes.  It isbased on the Real-Time Linux RT-FIFO mechanism.  Thertf_* functions are used by the real-time tasks; Linux processes usestandard 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 thenumber of bytes received.  This might be less than.I countif the function timed out or RT_NO_WAIT was specified and less than.I countbytes were available.  On failure, a negative value is returnedas described below..SH ERRORS.IP \fB-ENODEV\fP.I fifois not less than IPC_RTF_NO and RTF_NO..IP \fB-EINVAL\fP.I fifois not a valid fifo identifier..SH "AUTHOR"Jerry Epplin <JerryEpplin@worldnet.att.net>.SH "SEE ALSO".BR rtf_ipc_create (2), .BR rtf_ipc_destroy (2), .BR rtf_send (2)