Now I'm confused. In the second example, control was returned to the script after the 5 seconds. The external process continues, but as you say, that's a different problem,

But in the first example, whilst the signal handler was invoked after 5 seconds, the command completed ('yawn' was returned) and that did not happen until the external 10 second sleep completed?

Ie. Unless I am interpreting the output you posted incorrectly, the first example shows that the script cannot continue until the external command completes, even though the signal handler was invoked earlier than that.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re^6: How to timeout if a call to an external program takes too long by BrowserUk
in thread How to timeout if a call to an external program takes too long by deivakumar

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