I would like to start a system command from a Perl script, but let it be an interactive bash session. Either in the same terminal window, or in a new window.

In this case, the process I want to start from Perl is an ffmpeg conversion. That can take quite a while, and I would like to see the progress ffmpeg prints out.

If I start it with system(), I don't see the output.

If I use backticks, I get the output only after it is finished. Until then, I would have no idea what is going on.

There is also exec(), but that would terminate my perl script.

Is there yet another alternative?

Basically, I'm trying to do this: 

#!/usr/bin/perl
my $options = '....';
my @files = @ARGV || <>;
foreach my $file (@files) {
  my $outfile = "$file.mov";
  ####
  SOMETHING( "ffmpeg -i '$file' $options '$outfile'" ); 
}

[download]

where "something()" would either start the command in the current terminal and wait for it to finish, or maybe start a new terminal window, and also wait for it to finish.

In reply to start bash command from perl script: alternatives to system or backticks? by rduke15

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