* -c n: Do not handle more than n simultaneous connections. If there are n simultaneous copies of prog running, defer acceptance of a new connection until one copy finishes. n must be a positive integer. Default: 40.
* -x cdb: Follow the rules compiled into cdb by tcprules. These rules may specify setting environment variables or rejecting connections from bad sources. You can rerun tcprules to change the rules while tcpserver is running.
* -X: With -x cdb, allow connections even if cdb does not exist. Normally tcpserver will drop the connection if cdb does not exist.
* -B banner: Write banner to the network immediately after each connection is made. tcpserver writes banner before looking up $TCPREMOTEHOST, before looking up $TCPREMOTEINFO, and before checking cdb. This feature can be used to reduce latency in protocols where the client waits for a greeting from the server.
* -g gid: Switch group ID to gid after preparing to receive connections. gid must be a positive integer.
* -u uid: Switch user ID to uid after preparing to receive connections. uid must be a positive integer.
* -U: Same as -g $GID -u $UID. Typically $GID and $UID are set by envuidgid.
* -1: After preparing to receive connections, print the local port number to standard output.
* -b n: Allow a backlog of approximately n TCP SYNs. On some systems, n is silently limited to 5. On systems supporting SYN cookies, the backlog is irrelevant.
* -o: Leave IP options alone. If the client is sending packets along an IP source route, send packets back along the same route.
* -O: (Default.) Kill IP options. A client can still use source routing to connect and to send data, but packets will be sent back along the default route.
* -d: Delay sending data for a fraction of a second whenever the remote host is responding slowly. This is currently the default, but it may not be in the future; if you want it, set it explicitly.
* -D: Never delay sending data; enable TCP_NODELAY.