Colony

#include <stdio.h>

#include <sys/time.h>

#include <signal.h>

#include <unistd.h>

#include <stdlib.h>

volatile int i;

void *tick(int sig)

{

  printf("robot process paused. suspending\n");

  if(raise(SIGTSTP)<0)

    printf("could not kill self!\n");

  printf("robot resumed\n");

  return NULL;

}

int main(int argc, char *argp[], char *envp[])

{

  int ret;

  struct itimerval iv;

  printf("hello. I am a robot w/ env[0] %s\n", envp[0]);

  iv.it_interval.tv_sec = 1;

  iv.it_interval.tv_usec = 0;

  iv.it_value.tv_sec = 3;

  iv.it_value.tv_usec = 0;

  signal(SIGVTALRM, tick);

  ret = setitimer(ITIMER_VIRTUAL, &iv, NULL);

  printf("setitimer returned %d.\n waiting...\n", ret);

  fflush(stdout);

  i=0;

  while(1)

    i++;

  return 0;

}

#include <stdio.h>

#include <unistd.h>

#include <stdlib.h>

#include <signal.h>

#include <sys/wait.h>

int create_robot(char *execname, int id)

{

  /* do shared memory stuff here */

  int child;

  if((child = fork())<0){

    printf("error with fork!\n");

    return -1;

  }

  char *envp[] = {"test=1", NULL};

  if(!child){

    /* restore default sigchld handler */

    signal(SIGCHLD, SIG_DFL);

    execve(execname, NULL, envp);  //TODO: keep the other env. stuff around

    printf ("error! exec failed\n");

    exit(-1);

  }

  return child;

}

void *sig_chld_handler(int sig)

{

  pid_t pid;

  int cstat;

  printf("SIGCHLD: parent waiting\n");

  pid = waitpid(0, &cstat, WUNTRACED);

  printf("got %d from %d\n", cstat, pid);

  kill(pid, SIGCONT);

  return NULL;

}

  signal(SIGCHLD, sig_chld_handler);

  create_robot("robot_test/robot", 0);

  printf("returned to parent\n");

  gtk_gui_run(argc, argv);

  printf("parent exiting.\n");

  return 0;