I'm working on some code which is piped some input, calls another program to analyze it, and emails the results back to the user. The core of it is:

my ($analyze_in, $analyze_out);
my $kid_pid = open2($analyze_out, $analyze_in, $ANALYZE_PATH);
exit 0 unless $kid_pid;

while (my $line = <>) {
  print $analyze_in $line;
}
close $analyze_in;

my @result = <$analyze_out>;
die unless open my $sendmail_fh, '|' . $SENDMAIL_CMD;
print $sendmail_fh <<EOM;
From: $from_addr
To: $from_addr
Subject: Re: $subject

@result
EOM
close $sendmail_fh;
[download]

Functionally, it works just fine. However, in the email I receive, the second and all following lines of the analyzer output are indented one space. This indentation does not occur when running the analyzer directly from a shell prompt. There's also a Python version of the wrapper (the code above is actually from a Perl port of the Python code) and the Python version does not produce this indentation either - comparing the mail received from the Python and Perl versions is how I noticed it in the first place.

Any thoughts on what might be causing this or how to prevent it? (Note that s/^ // is not prevention...)