Could you not fix the buffering problem by turning on autoflush? 
...

$| = 1;    #Autoflush on
system("your_command | tee $filename");
$| = 0;    #Autoflush off

[download]
for(split(" ","tsuJ rehtonA lreP rekcaH")){print reverse . " "}print "\b.\n";

In reply to Re^2: How to cpture output of interactive command using perl.? by pobocks
in thread How to cpture output of interactive command using perl.? by Rapunzel

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