With program as you specify it, both work. With my own program (baton-metaquery from https://github.com/wtsi-npg/baton), even with local $| set, it doesn't.

However the question is why the 1-liner with the in-line MyPack package works, but copy/pasted MyPack code in to a .pm does not work. How can that be possible?

In reply to Re^2: Why is IPC::Open2 behaving differently in a .pm? by sendu
in thread Why is IPC::Open2 behaving differently in a .pm? by sendu

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