Just flush your output. The reason that "\n" made it printed, is because "\n" cause a flush of output immediately.

Update: Add $| ++ at the beginning of your code. 
This prints nothing:
print "a"; 
while (1) {}

This prints a:
print "a\n";
while (1) {}

This also prints a:
$| ++;
print "a";
while (1) {}

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In reply to Re: problem with tab completion by pg
in thread problem with tab completion by hotshot

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