Using Perl's Tk debugger, how can I set a breakpoint in my Perl library?

I have a large Perl script that开发者_运维技巧 is broken into several Perl libraries. In the Perl Tk debugger, I'd like to be able to set a breakpoint in one of the library files. The only way I know how to set a breakpoint in ptkdb is to navigate to the line in the source code pane. However, that source code pane only has the top level Perl script.

How can I set a breakpoint in my library?

FYI, I know I can use Eclipse with a perl plugin to accomplish this task, but I'd like to do it in ptkdb because the Eclipse setup time is extensive.

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If you're talking about *.pm files:

file -> open -> select the module you want -> select the line you want && ctrl+b.