I am looking for a document explains all the signals' meaning and trigger.

The signals special to Perl, like __WARN__ and __DIE__, are documented in %SIG, the other signals are generally POSIX signals, which you can read about for example in signal(7) like here and here, or in Signal (IPC). Note that a lot of signals may be OS-specific. If you could tell us what you want to use them for (and on which platforms), perhaps we can give more specific advice.

Oh! Thank you so much! Learned something really new today, those SIGs are actually POSIX and IPC stuff, no wonder I don't get much useful results on my search before. I am working on Windows tho.

The closest Windows has to signals is Ctrl-C and Ctrl-Break, and I believe those are mapped to signals. I don't remember which.

> I am working on Windows tho.

They^(who?;-) say Windows is POSIX compatible, so many things work.

But it's complicated to get to decent info here, hence you need to test.

IIRC even if a signal is supported details may differ.

Cheers Rolf
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