set text {56 ipv4 packets transmitted and 20 ipv6 packets transmitted}
set results [regexp -inline -all {\y\d+\y} $text]
puts $results
# 56 20
set results2 [regexp -inline -all {\m\d+\M} $text]
puts $results2
# 56 20
c2V0IHRleHQgezU2IGlwdjQgcGFja2V0cyB0cmFuc21pdHRlZCBhbmQgMjAgaXB2NiBwYWNrZXRzIHRyYW5zbWl0dGVkfQpzZXQgcmVzdWx0cyBbcmVnZXhwIC1pbmxpbmUgLWFsbCB7XHlcZCtceX0gJHRleHRdCnB1dHMgJHJlc3VsdHMKIyA1NiAyMAoKc2V0IHJlc3VsdHMyIFtyZWdleHAgLWlubGluZSAtYWxsIHtcbVxkK1xNfSAkdGV4dF0KcHV0cyAkcmVzdWx0czIKIyA1NiAyMA==