Another heuristic is to look for use DynaLoader or use XSLoader in any of the modules.

XS code also often comes with a file called typemap which is used by the XS build system to map between Perl data structures and C data structures.

And ppport.h is often bundled. This is a C header file which, as I understand it, smooths over the differences between versions of the Perl API.

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re^2: How to know if a CPAN module uses XS by tobyink
in thread How to know if a CPAN module uses XS by bcarroll

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