rtf_create_rt_handler.3

rtlinux-3.1源代码

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.TH "rtf_create_rt_handler" "3" 
.SH "NAME" 
rtf_create_rt_handler \(em install a handler for realtime fifo data 
.SH "SYNOPSIS" 
.PP 
.nf 
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#include <rtl_fifo.h> 
 
int \fBrtf_create_rt_handler\fP(unsigned int \fBfifo\fR, int (* \fBhandler\fR)()); 
.fi 
.SH "DESCRIPTION" 
.PP 
\fBrtf_create_rt_handler\fP installs  a  handler which is executed when \fBrtf_put\fP or \fBrtf_get\fP  
is called on the specified   real-time fifo (RT-FIFO).   \fBfifo\fR is an RT-FIFO that must have previously been created with a call to \fBrtf_create\fP.  \fBhandler\fR  is  then called whenever that fifo is accessed in RT mode. 
.PP 
Note that the handler is called in the context of the task that uses 
\fBrtf_put\fP or \fBrtf_get\fP. You can use semaphores 
to take handler actions asynchronously: use \fBsem_wait(3)\fP in a thread, and post the semaphore from the handler. 
.PP 
The RT-FIFO is a mechanism,  implemented  as  a  character device,  to  communicate between realtime software components (either in threads or handlers), 
and between realtime software and ordinary Linux processes.  The rtf_* functions are used in RT mode;  Linux  processes use standard character device access functions, such  as  \fBread(2)\fP,  \fBwrite(2)\fP  and \fBselect(2)\fP. 
.SH "RETURN VALUE" 
.PP 
On success, 0 is returned.  On failure, a negative value is returned as described below. 
.SH "ERRORS" 
.IP "-EINVAL" 10 
\fBfifo\fR is greater than or equal to RTF_NO, or is not a valid RT-FIFO identifier; or \fBhandler\fR is NULL. 
.SH "SEE ALSO" 
\fIrtf_create(3) (link to URL rtf_create.3.html) \fR, \fIrtf_create_handler(3) (link to URL rtf_create_handler.3.html) \fR, \fIrtf_destroy(3) (link to URL rtf_destroy.3.html) \fR, \fIrtf_get(3) (link to URL rtf_get.3.html) \fR, \fIrtf_put(3) (link to URL rtf_put.3.html) \fR 
.PP 
\(co2001 FSMLabs Inc. 
.PP 
All rights reserved. 
...\" created by instant / docbook-to-man, Thu 26 Jul 2001, 11:19