Re^3: Problem with exit status of bash script

do you have any good docs for me to read about IPC in perl?

Sure:

Perl documentation has perlipc;
Chapter 15 of the Camel Book¹ is devoted to “Interprocess Communication”; and
the Monastery has a tutorial section devoted to Threads, Multi-Processing, and Inter-Process Communication.

Hope that helps,

¹Tom Christiansen, brian d foy & Larry Wall, with Jon Orwant, Programming Perl, 4^th Edition, 2012.

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