In an XS program it appears that it is slightly more complicated than this as the XSUB.h for perl 5.72 has :

   #    define opendir             PerlDir_open
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having previously undefined opendir.

PerlDir_open itself is defined in iperlsys.h in 5.72 - this is so that it can be made to fit in with the whole PerlIO thing.

Probably the easiest way of finding out what is going on in here is to look at the implementation of pp_open_dir in pp_sys.c and then work backward from there.

/J\
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