Re: problem with redirection and piping

It's because when you execute a piped chain of programs, the last program in the chain will receive the signal.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

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Comment on Re: problem with redirection and piping

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Re^2: problem with redirection and piping by ikegami (Patriarch) on Jan 10, 2010 at 08:34 UTC
You seem to be implying that only the last command receives the signal, but that's not true. We know the Perl script received the signal since we can observe the signal handler sending output to STDERR. I presume what is happening is that the signal is sent to both `perl` and `tee`, and that `tee` exits before reading the text sent by `perl` in response to the signal. If you do `kill -INT 1234` where `1234` is `perl`'s pid, `tee` won't receive the signal, so it will log the text `perl` outputs from the signal handler.	[reply] [d/l] [select]
Re^3: problem with redirection and piping by Anonymous Monk on Jan 10, 2010 at 13:04 UTC
excellent, you are right. By sending the INT using PID it works as expected. Great, thats why you people were rocking. Thanks a lot and tons...	[reply]