Make sure B has autoflush turned on before the print for STDOUT... 
$| = 1;
print ...

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Also, terminate the print with a '\n'. Though you haven't shown it, I'm assuming A reads back the line printed from B. (If not, B can hang on the print waiting for A to read it if B prints a large enough string, filling the pipe.) Update: From your code, it looks like A sends the '\n' to B so the comment about terminting the print may not apply.

In reply to Re: Pipe problems by bluto
in thread Pipe problems by tran_sonic

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