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A question about signals in Unix


 
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# 1  
Old 10-29-2009
A question about signals in Unix

Whats a signal 0. An exhaustive search on signals landed me nowhere.

Is it possible to do something like this trap "echo $var" 0.

If so what signal does this trap catch ?
# 2  
Old 10-29-2009
Signal 0 is a pseudo-signal, understood by ksh and compatibles, which means EOF. This "signal" gets triggered whenever the script finishes it's execution, no matter how. It's very nice to have if you want to clean up after your script (eg. temporary files), and don't want to write the code multiple times. Pretty similar to the POSIX atexit(3) C function.
# 3  
Old 10-29-2009
well if this is a trap to catch the end of execution of script can Ctrl+C stop this execution.?

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