Re: [Discuss-gnuradio] FIFOs

[Eric Blossom]

On Wed, Jul 23, 2008 at 02:32:06PM +0200, Sebastiaan Heunis wrote:
> Hi
> 
> I'm trying to write USRP data to a FIFO and read it out using a C++
> app.  I can't get it to work.  What I did was to type 'mkfifo myfifo'
> in the shell.  This is the output to ls -l myfifo.
> 
> prw-r--r-- 1 sebastiaan sebastiaan 0 2008-07-23 14:20 myfifo
> 
> I then tried to run my application, passing myfifo as a parameter.
> This is the line of Python code that sets up the filesink.
> 
> self.dst = gr.file_sink(gr.sizeof_gr_complex, filename)
> 
> When I run the application, it hangs and when I press CTRL+C, I get
> the following output.
> 
> myfifo: Interrupted system call
> terminate called after throwing an instance of 'std::runtime_error'
>   what():  can't open file
> Aborted
> 
> Can anyone please tell me if there are any other steps to get this to work?
> 
> Thank you very much.
> 
> Sebastiaan

You need to have a process reading on the FIFO too.

I suggest trying this out by hand on the command line first, using
"cat" to read and write data from the fifo.

Eric