gcoap: Update CLI example for rebase on sock

examples/gcoap/Makefile

-# Default Makefile, for host native networking
+# Default Makefile, for host native GNRC-based networking
 
 # name of your application
 APPLICATION = gcoap
@@ -29,8 +29,6 @@ BOARD_BLACKLIST := nrf52dk
 USEPKG += nanocoap
 # Required by nanocoap, but only due to issue #5959.
 USEMODULE += posix
-# Required by nanocoap to compile nanocoap_sock.
-USEMODULE += gnrc_sock_udp
 
 # Include packages that pull up and auto-init the link layer.
 # NOTE: 6LoWPAN will be included if IEEE802.15.4 devices are present
@@ -38,6 +36,7 @@ USEMODULE += gnrc_netdev_default
 USEMODULE += auto_init_gnrc_netif
 # Specify the mandatory networking modules
 USEMODULE += gnrc_ipv6_default
+USEMODULE += gnrc_sock_udp
 USEMODULE += gcoap
 # Additional networking modules that can be dropped if not needed
 USEMODULE += gnrc_icmpv6_echo

examples/gcoap/Makefile.slip

-# Border router Makefile for SLIP based networking
+# Border router Makefile for GNRC and SLIP based networking
 # Assumes use of SAMR21 board
 
 # name of your application
@@ -45,14 +45,13 @@ CFLAGS += -DSLIP_BAUDRATE=$(SLIP_BAUDRATE)
 USEPKG += nanocoap
 # Required by nanocoap, but only due to issue #5959.
 USEMODULE += posix
-# Required by nanocoap to compile nanocoap_sock.
-USEMODULE += gnrc_sock_udp
 
 # Include packages that pull up and auto-init the link layer.
 # NOTE: 6LoWPAN will be included if IEEE802.15.4 devices are present
 USEMODULE += gnrc_netdev_default
 USEMODULE += auto_init_gnrc_netif
 # Specify the mandatory networking modules
+USEMODULE += gnrc_sock_udp
 USEMODULE += gcoap
 # Add a routing protocol
 USEMODULE += gnrc_rpl

examples/gcoap/README.md

 # gcoap Example
 
-This application provides command line access to gcoap, a GNRC implementation of CoAP. See the [CoAP spec][1] for background, and the Modules>Networking>GNRC>CoAP topic in the source documentation for the structure of the implementation.
+This application provides command line access to gcoap, a high-level API for CoAP messaging. See the [CoAP spec][1] for background, and the Modules>Networking>CoAP topic in the source documentation for detailed usage instructions and implementation notes.
 
 We support two setup options for this example:
 

examples/gcoap/gcoap_cli.c

@@ -96,22 +96,27 @@ static ssize_t _stats_handler(coap_pkt_t* pdu, uint8_t *buf, size_t len)
 static size_t _send(uint8_t *buf, size_t len, char *addr_str, char *port_str)
 {
     ipv6_addr_t addr;
-    uint16_t port;
     size_t bytes_sent;
+    sock_udp_ep_t remote;
+
+    remote.family = AF_INET6;
+    remote.netif  = SOCK_ADDR_ANY_NETIF;
 
     /* parse destination address */
     if (ipv6_addr_from_str(&addr, addr_str) == NULL) {
         puts("gcoap_cli: unable to parse destination address");
         return 0;
     }
+    memcpy(&remote.addr.ipv6[0], &addr.u8[0], sizeof(addr.u8));
+
     /* parse port */
-    port = (uint16_t)atoi(port_str);
-    if (port == 0) {
+    remote.port = (uint16_t)atoi(port_str);
+    if (remote.port == 0) {
         puts("gcoap_cli: unable to parse destination port");
         return 0;
     }
 
-    bytes_sent = gcoap_req_send(buf, len, &addr, port, _resp_handler);
+    bytes_sent = gcoap_req_send2(buf, len, &remote, _resp_handler);
     if (bytes_sent > 0) {
         req_count++;
     }