.. _libmemif_examples_doc: Libmemif Examples ================= Example source code is located in `.../vpp/extras/libmemif/examples/` directory. The compiled binaries are located in `.../vpp/extras/libmemif/build/examples/`. ICMP Responder -------------- **Application Source Code**: `.../vpp/extras/libmemif/examples/icmp_responder` In this example, memif endpoint connects to an external application. The example application can resolve ARP and reply to ICMPv4 packets. The program will exit once the interface is disconnected Memif receive mode: interrupt. VPP (memif master) <--> icmp_responder app (memif slave) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Start VPP and configure memif interface:: make run ... DBGvpp# create interface memif id 0 master DBGvpp# set int state memif0/0 up DBGvpp# set int ip address memif0/0 192.168.1.2/24 Start icmp_responder example app:: ./examples/icmp_responder Memif in slave mode will try to connect every 2 seconds. If connection establishment is successful, the `memif connected` message will show:: INFO: memif connected! **Note**: Error messages like "unmatched interface id" are printed only in debug mode. Verify that the memif is connected on VPP side:: DBGvpp# sh memif interface memif0/0 remote-name "ICMP_Responder" remote-interface "memif_connection" id 0 mode ethernet file /run/vpp/memif.sock flags admin-up connected listener-fd 12 conn-fd 13 num-s2m-rings 1 num-m2s-rings 1 buffer-size 0 master-to-slave ring 0: region 0 offset 32896 ring-size 1024 int-fd 16 head 0 tail 0 flags 0x0000 interrupts 0 master-to-slave ring 0: region 0 offset 0 ring-size 1024 int-fd 15 head 0 tail 0 flags 0x0001 interrupts 0 Send ping from VPP to icmp_responder (Default IPv4: 192.168.1.1):: DBGvpp# ping 192.168.1.1 64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=.1888 ms 64 bytes from 192.168.1.1: icmp_seq=3 ttl=64 time=.1985 ms 64 bytes from 192.168.1.1: icmp_seq=4 ttl=64 time=.1813 ms 64 bytes from 192.168.1.1: icmp_seq=5 ttl=64 time=.1929 ms Statistics: 5 sent, 4 received, 20% packet loss Loopback -------- **Application Source Code**: `.../vpp/extras/libmemif/examples/loopback` In this example, two memif endpoints are connected to create a loopback. Once connected, a test packet is sent out the memif master interface to the memif slave interface, which replies with the same packet in a zero-copy way. In reverse mode, the packet is sent from the slave interface and is looped back by the master interface. Running The Loopback Application ++++++++++++++++++++++++++++++++ Start the loopback example:: ./examples/loopback You should see the `Received correct data.` message:: INFO: Received correct data. INFO: Stopping the program