I exploit the %SIG hash, found most of values are "undef", some of are "IGNORE"; 

perl -MData::Dumper -E ' print Dumper \%SIG '

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What confuse me is that, if SIGnal's process was set to undef,

how the signal will be processed when it come up ? ( ignore ? call the default action defined by OS ?)

BTW, if I want to set SIGPIPE 's handle to default; how can i to get it ? 

$SIG{PIPE} = undef 

or 

$SIG{PIPE} = ""

or 

#some thing else;

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very thanks your patient to answer this :)

In reply to perl SIGnal process by chinaxing

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