You seem to have the method correct: use backticks (see perlop) to capture the output of free into a scalar. Then split on whitespace to get the "words": 
my $free = `free`;
my @words = split /\s+/, $free;

shift @words if $words[0] eq '';

[download]

shift removes an empty string from @words caused by $free starting with spaces.

In reply to Re: Splitting output of a system command into an array by FunkyMonk
in thread Splitting output of a system command into an array by sKiBa

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