Hi,

I want to open a process and read only its STDERR. This is very important because of STDOUT and STDERR interlacing. I can't just process one and then process the other because then STDOUT and STDERR will be deinterlaced. Anyway, here's what I tried using IPC::Open3:

my ($wtr, $rdr, $err);
$wtr = '<&';
$rdr = '>&';
my $pid = open3($wtr, $rdr, $err, $program, @arguments);
while (<$err>) {
   print STDERR $_;
   process_stderr($_);
}

[download]

According to the IPC::Open3 manpage, the special strings '<&' and '>&' should do what I want, I think. I think I'm not understanding the manpage correctly.

I've tried something ugly using fork(), I've tried a plain system(), I've tried coding it in C, etc. I searched the archives before posting, but could find nothing. Please help me monks!

Thanks!

In reply to Reading only STDERR by nomis80

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