c++ grab in position signal

"axis-remote --mdi 'G0 F100000 X100 Y100 Z100' "

//START
comp_id = hal_init(comp_name);
hal_ready(comp_id);

//CREATE PIN(S)
r = hal_pin_bit_newf(HAL_IN, ...........................);

Then you can directly access MDI eg

static int sendMdiCmd(char *mdi)
{
  EMC_TASK_PLAN_EXECUTE emc_task_plan_execute_msg;

  strcpy(emc_task_plan_execute_msg.command, mdi);
  emc_task_plan_execute_msg.serial_number = ++emcCommandSerialNumber;
  emcCommandBuffer->write(emc_task_plan_execute_msg);

  return 0;
}

Do other stuff in a loop

//EXIT
hal_exit(comp_id);

/*
hal file additions:-

loadusr -W mdipump

net sig1 mdipump.commandfinished motion.in-position
net sig2 mdipump.homed halui.joint.2.is-homed
net sig3 mdipump.machineon halui.machine.is-on

Need a file ~/linuxcnc/gcode.ngc.

My test file just contained this
G40 G90
G54
G21 G17
G40 G8
F2000
G01 X0 Y0 Z20
G01 X160
G01 X-160
G01 Y65
G01 Y-65
G0 Z 5

The component will wait for the machine to be switched on and the Z axis to be homed 
and will then read a gcode file line by line and pump it to axis-remote until finished.

It waits between lines until motion.in-position is TRUE before sending another one.

*/


component mdipump                     "This component reads a file and pushes MDI commands to Linuxcnc";

pin in bit commandfinished = 0        "signal last command completed - connect to motion.in-position";
pin in bit homed = 0                  "signal that machine is homed and ready for commands - connect to last axis to home - halui.joint.2.is-homed";
pin in bit machineon = 0              "signal to ensure machine is on - connect to halui.machine.is-on"; 
option singleton yes;               
option userspace yes;

author "ArcEye <arceyeATmgwareDOTcoDOTuk>";
license "GPL";
;;

#include <stdio.h>    /* Standard input/output definitions */
#include <stdlib.h> 
#include <stdint.h>   /* Standard types */
#include <string.h>   /* String function definitions */
#include <unistd.h>   /* UNIX standard function definitions */
#include <fcntl.h>    /* File control definitions */
#include <errno.h>    /* Error number definitions */
#include <signal.h>
#include <pwd.h>

int done = 0;

void adios(int sig) { done = 1; }


void user_mainloop(void)
{
char filepath[80];
int progress = 0;
char line[80];
char cmdline[80];

    // get user home dir
struct passwd *pw = getpwuid(getuid());
const char *homedir = pw->pw_dir;

sprintf(filepath, "%s/linuxcnc/gcode.ngc", homedir);
FILE *fp1;
fp1 = fopen(filepath, "r");
    
signal(SIGINT, adios);
signal(SIGTERM, adios);
      
    while(!done)
        {
        usleep(250000);
        
        FOR_ALL_INSTS()  
            { 
            if(homed && machineon)
                {
                switch(progress)
                    {
                    case 0: 
                            if(!feof(fp1))
                                {
                                fgets(line, sizeof(line), fp1);  
                                fprintf(stderr,"Line:- %s ", line);// debug
                                sprintf(cmdline, "axis-remote --mdi '%s'", line);
                                system(cmdline);
                                progress = 1;
                                break;
                                }
                            else
                                {
                                done = 1;
                                fprintf(stderr,"File %s completed", filepath);
                                break;
                                }
                
                    case 1: if(!commandfinished)
                                break;
                            else
                                progress = 0;
                        
                    default:
                            break;               
                
                    }
                }
            }
        }
    exit(0);
}