You could try something like 
open SYS, "command |" or die "$!";
while (<SYS>) {
  print
}
close SYS;

[download]
but a lot depends on whether 'command' buffers its output, among other variables. You should probably read perldoc perlipc for more insight.

In reply to Re: print output from system command in real time by moot
in thread print output from system command in real time by Anonymous Monk

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