just-in-time debugging?

Yes, I use that to get a symbolic stack dump after a crash, although I find that the gdb so invoked doesn't accept interactive commands, and I have to use 'kill -9' afterwards. Here's the code I use:

void dump_stack(int signum)

{
    (void) signum;
    char s[160];
    // The right command to execute depends on the program.  Adjust to taste.
    system("echo 'info threads\nbt\nthread 3\nbt\nthread 4\nbt\nthread 5\nbt\n' > gdbcmd");
 
    sprintf(s, "gdb -batch -x gdbcmd %s %d", argv0, (int) getpid());
    printf("Crashed!  Starting debugger to get stack dump.  You may need to kill -9 this process afterwards.\n");
    system(s);
    exit(1);

}

main() {
signal(SIGSEGV, dump_stack);
signal(SIGBUS, dump_stack);
...