Avoid the shell. In addition to the usual benefits, this problem goes away.

You should use IPC::Run3 or IPC::Run, but low-level IPC::Open3 will be easy enough to use here.

use File::Spec::Functions qw( devnull );
use IPC::Open3            qw( open3 );

{
   my @cmd = (
      $tshark_binary => (
         -r => $pcap,
         -e => "frame.number",
         -e => "frame.time_epoch",
         -e => "ip.src",
         -e => "ip.id",
         -T => "text",
         -T => "fields",
         -E => "separator=,"
      ),
   );

   open(local *CHILD_STDIN,  '<', devnull) or die $!;
   open(local *CHILD_STDOUT, '>', $file_temp) or die $!;

   my $pid =
      open3('<&CHILD_STDIN', '>&CHILD_STDOUT', '>&STDERR', @cmd);
   waitpid($pid, 0);
}
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