component udp "Connects to laser esp8266 of laser distance sensor (ODSL 9/D26-450-S12 - Optical distance sensor)";

//http://www.leuze.com/selector/ci_pages/downloads.php?supplier_aid=50111159&key=9f0f255e2c9fb97529e5d7196847f76a174a9a206b9ec072f3d0228255151e6f

pin in float pos_cmd0;
pin in float pos_cmd1;
pin in float pos_cmd2;

pin out float pos_fb0;
pin out float pos_fb1;
pin out float pos_fb2;

instanceparam int pincount = 6;

option MAXCOUNT 16;

function _;

option extra_inst_setup yes;
variable int sockfd;

author "test";
license "GPL"; // indicates GPL v2 or later
;;
#define MAX_DEV 3

RTAPI_MP_ARRAY_STRING(ip, MAX_DEV, "IP of sensor")
RTAPI_MP_ARRAY_INT(port, MAX_DEV, "UDP port")

#include <arpa/inet.h>
#include <ifaddrs.h>
EXTRA_INST_SETUP(){
    rtapi_print("hallo\n");

    int ret;

    sockfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
    if (sockfd < 0) {
        rtapi_print("ERROR: can't open socket: %s\n", strerror(errno));
        return -errno;
    }

    struct sockaddr_in server_addr;
    struct sockaddr_in local_addr;

    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(port[extra_arg]);
    server_addr.sin_addr.s_addr = inet_addr(ip[extra_arg]);

    local_addr.sin_family      = AF_INET;
    local_addr.sin_addr.s_addr = INADDR_ANY;

    ret = connect(sockfd, (struct sockaddr *) &server_addr, sizeof(struct sockaddr_in));
    if (ret < 0) {
        rtapi_print("ERROR: can't connect: %s\n", strerror(errno));
        return -errno;
    }



    struct timeval timeout;
    timeout.tv_sec = 0;
    timeout.tv_usec = 10;

    ret = setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout));
    if (ret < 0) {
        rtapi_print("ERROR: can't set socket option: %s\n", strerror(errno));
        return -errno;
    }

    timeout.tv_usec = 10;
    setsockopt(sockfd, SOL_SOCKET, SO_SNDTIMEO, (char *)&timeout, sizeof(timeout));
    if (ret < 0) {
        rtapi_print("ERROR: can't set socket option: %s\n", strerror(errno));
        return -errno;
    }


    return 0;
}

FUNCTION(_) {
    pos_fb0 = pos_cmd0;
    pos_fb1 = pos_cmd1;
    pos_fb2 = pos_cmd2;
    uint8_t buf[16];

    buf[0] = 0x01;
    buf[1] = 0x42;
    buf[2] = 0x00;
    buf[3] = 0x01;

    int ret = send(sockfd,buf,4,0);
    if (ret < 0) {
        rtapi_print("send fail %s\n", strerror(errno));
    }
}














Error:
machinekit@beaglebone:~$ instcomp --install ./components/udp.icomp
Compiling realtime udp.c
In file included from /home/machinekit/git/machinekit/include/rtapi.h:1027:0,
                 from udp.c:4:
./components/udp.icomp:27:23: error: ‘ip’ undeclared here (not in a function)
/home/machinekit/git/machinekit/include/rtapi_export.h:32:30: note: in definition of macro ‘MODULE_INFO2’
     t rtapi_info_##a##_##b = c; EXPORT_SYMBOL(rtapi_info_##a##_##b);
                              ^
/home/machinekit/git/machinekit/include/rtapi.h:1067:3: note: in expansion of macro ‘MODULE_PARM’
   MODULE_PARM(var,"1-" RTAPI_STRINGIFY(num) "s");  \
   ^
./components/udp.icomp:27:1: note: in expansion of macro ‘RTAPI_MP_ARRAY_STRING’
./components/udp.icomp:28:20: error: ‘port’ undeclared here (not in a function)
/home/machinekit/git/machinekit/include/rtapi_export.h:32:30: note: in definition of macro ‘MODULE_INFO2’
     t rtapi_info_##a##_##b = c; EXPORT_SYMBOL(rtapi_info_##a##_##b);
                              ^
/home/machinekit/git/machinekit/include/rtapi.h:1059:3: note: in expansion of macro ‘MODULE_PARM’
   MODULE_PARM(var,"1-" RTAPI_STRINGIFY(num) "i");  \
   ^
./components/udp.icomp:28:1: note: in expansion of macro ‘RTAPI_MP_ARRAY_INT’
./components/udp.icomp: In function ‘extra_inst_setup’:
./components/udp.icomp:47:36: error: ‘extra_arg’ undeclared (first use in this function)
./components/udp.icomp:47:36: note: each undeclared identifier is reported only once for each function it appears in
/home/machinekit/git/machinekit/src/Makefile.modinc:123: recipe for target 'udp.o' failed
make: *** [udp.o] Error 1