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Create two named pipes, p1 and p2. Run the commands:
echo -n x | cat - p1 > p2 &
cat
On screen, it will not appear that anything is happening, but if you run top (a command similar to ps for showing process status), you'll see that both cat programs are running like crazy copying the letter x back and forth in an endless loop.
After you press ctrl-C to get out of the loop, you may receive the message “broken pipe”. This error occurs when the process reading the pipe closes its end while a process is writing to a pipe. Since the reader is gone, the data has no place to go. Normally, the writer will finish writing its data and close the pipe. At this point, the reader sees the EOF (end of file) and executes the request.
Whether or not the “broken pipe” message is issued depends on events at the exact instant the ctrl-C is pressed. If the second cat has just read the x, pressing ctrl-C stops the second cat, pipe1 is closed and the first cat stops quietly, i.e., without a message. On the other hand, if the second cat is waiting for the first to write the x, ctrl-C causes pipe2 to close before the first cat can write to it, and the error message is issued. This sort of random behavior is known as a “race condition”.
Source (online linux journal)
Regards
Manoj
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