This should work 

use strict;
use warnings;

my $address = 'myemail@whatever.com';
my $subject = "Comments Version: $version  ID: $ID";

system( "mail $address -s '$subject' < blah6.txt" ) == 0
    or die "mail failed:  $?";

[download]
I made three changes to the code you posted:
  1. Eliminated the s/// line since escaping is required only in a double-quoted context, but above the @ is being given in a single-quoted context, so no variable interpolation occurs.
  2. I put the RHS of the assignment to $subject in double quotes, because in this case we do want interpolation (of $Version and $ID).
  3. In the argument to system I put $subject in single quotes, because otherwise the shell would interpret the various words in $subject as different arguments, as opposed to the single argument for -s
This is definitely a little quoting workout! You may want to read the docs on quoting, to best make sense of the above.

the lowliest monk

In reply to Re^5: System Command Issues by tlm
in thread System Command Issues by blanket

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