For Q. 1), you could just grab the remainder of the string: 
use strict;
use warnings;

for my $row (
    'MACHINE_CLASS=9000/800/L3000-5x',
    'MACHINE_CLASS=ia64 hp server rx2600'
) {
    my ($machine_class) = $row =~ (/MACHINE_CLASS=\s*(.*)/);
    print "$machine_class\n";
}

__END__

9000/800/L3000-5x
ia64 hp server rx2600

[download]
Take a look at perlre to see what \w matches.

In reply to Re: @ Regular expression: by toolic
in thread @ Regular expression: by siddheshsawant

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