This is likely your problem:

$memcmd=`/usr/sbin/prtconf | grep Memory`;
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...which you then later try to use as a new FileHandle.

Try changing that line* to:

$memcmd="/usr/sbin/prtconf | grep Memory |";
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The alternative is to capture the full output of qx//:

@memcmd_output = `/usr/sbin/prtconf | grep Memory`;
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... and then iterate over that ...

for my $line( @memcmd_output ){
   # ... do your stuff on $line
}
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* Updated: ikegami pointed out a missing trailing vertical bar.

s**lil*;  $*=join'',sort split q**;  s;.*;grr; &&s+(.(.)).+$2$1+; $; =
qq-$_-;s,.*,ahc,;$,.=chop for split q,,,reverse;print for($,,$;,$*,$/)
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