Further to jwkrahn's reply, consider: 
>perl -wMstrict -le
"my $str = '123 456 789';
 print qq{1st match: $1} if $str =~ m{ (\d{3}) }xmsg;
 print qq{2nd match: $1} if $str =~ m{ (\d{3}) }xmsg;
 print qq{3rd match: $1} if $str =~ m{ (\d{3}) }xmsg;
"
1st match: 123
2nd match: 456
3rd match: 789

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Try those matches without the  //g modifier.

In reply to Re^2: regex only matching from last match by AnomalousMonk
in thread regex only matching from last match by Foxpond Hollow

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