There is a very good and readable discussion of this in chapter 20 of Advanced Perl Programming.

The only way to get much deeper into it starts with fetching a copy of the current perl version: 

rsync -auvz rsync://ftp.linux.activestate.com/perl-current/ /usr/local
+/lib/perl/bleadperl/

[download]

Then building a debugging-enabled perl with debugging symbols in it (note the make option, this cost me some hours to find out): 

pushd /usr/local/lib/perl/bleadperl
make realclean
rm config.sh
./Configure -de -Dcc=gcc -Dusedevel -Doptimize=-g3
make OPTIMIZE=-g3
make test
popd

[download]

And then starting up your favorite debugger with a breakpoint at run.c:Perl_runops_debug, e.g., in gdb: 

break run.c:Perl_runops_debug
run -e '$foo = 42'

[download]

If that is your idea of fun, of course ...

Christian Lemburg
Brainbench MVP for Perl
http://www.brainbench.com

In reply to Re: How does Perl do it it's thing? by clemburg
in thread How does Perl do it it's thing? by bladx

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