READ-SEQUENCE and USOCKET

Hi I am reading from a uosocket:stream-usocket. My sequence is 100 octets long, but I know the other party is sending UP TO 100 octets. If the other party sends less than 100 octets, read-sequence/usocket-stream (at least the version on LW) hangs. Should I just do a loop, checking for the "end marker"? Thanks All the best -- Marco Antoniotti