in reply to print output from system command in real time

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.

Replies are listed 'Best First'.
Re^2: print output from system command in real time
by boat73 (Scribe) on May 10, 2005 at 18:53 UTC
    Thanks but that did not work. I built a standalone exe from the following code. Oh and I am doing this on windowz to make it even more fun. 
    until($cnt == "100"){
print "COUNT IS $cnt\n";
sleep 5;
$cnt++;
}

    [download]
    I then call the exe within perl. With the code you supplied it still waits until completion before printing. I even tried setting autoflush with the code below. 
    open SYS, "c:\\temp\\junk.exe |" or die "$!";
$oldfh=select(SYS);
$| = 1;
select($oldfh);
$| = 1;
while (<SYS>) {
print
}
close SYS;

    [download]
[reply]
[d/l]
[select]
[reply]
[d/l]
        Hmmm, the problem is that the exe I am truly running does the same thing and I am unable to modify that code. System didn't work, still waits til completion to print.
[reply]

In Section Seekers of Perl Wisdom