Signal handler

sighandler.cpp

#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>

void sighandler(int signum)
{
  printf("Process %d got signal %d\n", getpid(), signum);

  // Get process executive path
  // http://stackoverflow.com/questions/646241/c-run-a-system-command-and-get-output
  char rdcom[1024] ={'\0'};
  sprintf(rdcom, "readlink -f /proc/%d/exe", getpid()); 
  
  FILE *fp;
  char result[1024];

  /* Open the command for reading. */
  fp = popen(rdcom, "r");
  if (fp == NULL) {
    printf("Failed to get the process executive path\n" );
    return;
  }
  fgets(result, sizeof(result)-1, fp);
  pclose(fp);
  // ================================================================================ //
  
  // Trim newline
  // http://stackoverflow.com/questions/2693776/removing-trailing-newline-character-from-fgets-input
  size_t ln = strlen(result) - 1;
  if (*result && result[ln] == '\n') result[ln] = '\0';
  printf("Process %d path: %s\n", getpid(), result);
  
  char command[1024] ={'\0'};
  sprintf(command, "gdb %s %d", result, getpid()); 
  printf("%s\n",command);
  system(command);
  exit(1);
}

void cause_SIGSEGV(char* null_ptr)
{
    *null_ptr = 's';
}

int main()
{
    signal(SIGSEGV, sighandler);

    char* null_ptr = NULL;
    cause_SIGSEGV(null_ptr);

    return 0;
}