Use the strchg(1M), as shown in the second command line
system% cat > tmp/mystreams ttcompat ldterm u8lat1 ptem ^D system% strchg -f /tmp/mystreams
Be sure that you are either root or the owner of the device when you use strchg(1).
Run the strconf command to examine the current configuration.
system% strconf ttcompat ldterm u8lat1 ptem pts system%
Run the strchg command to reset the original configuration.
system% cat > /tmp/orgstreams ttcompat ldterm ptem ^D system% strchg -f /tmp/orgstreams