<networking> A Unix command that sends packets to a host and reports performance statistics. The number of packets, delay between packets and packet length can all be specified. The spray command uses the Remote Procedure Call (RPC) protocol to send a one-way stream of packets to the sprayd daemon on the given host. With the "-i" option, spray uses the Internet Control Message Protocol (ICMP) instead of RPC. Normally these will be echoed automatically, creating a return stream.
Unix manual page: spray(1M).