int main(void)
{
shm_name[0] = 't';
shm_name[1] = 'e';
shm_name[2] = 's';
shm_name[3] = 't';
size = 4;
shm_addr = my_shm_create (shm_name, size);
shm_addr = my_shm_open (shm_name);
*shm_addr = 0;
printf ("1\n");
*shm_addr = 1;
while(*shm_addr != 0)
{}
printf ("3\n");
*shm_addr = 1;
while(*shm_addr != 0)
{}
printf ("5\n");
*shm_addr = 1;
while(*shm_addr != 0)
{}
CloseAndUnlink();
return (0);
}
void
initSemSHM(int pid)
{
printf ("\n");
#ifdef VERBOSE
printf("Creating flags semaphore for procces %d\n", pid);
#endif
sem_flags = sem_open (sem_flags_name, O_CREAT | O_EXCL, 0600, 1);
#ifdef VERBOSE
if (sem_flags == SEM_FAILED)
{
perror ("ERROR: sem_open() failed");
}
printf("Creating sync semaphore for procces %d\n", pid);
#endif
sem_sync = sem_open (sem_sync_name, O_CREAT | O_EXCL, 0600, 0);
#ifdef VERBOSE
if (sem_sync == SEM_FAILED)
{
perror ("ERROR: sem_open() failed");
}
printf ("Creating Shared memory '%s' \n", shm_name);
#endif
shm_addr = my_shm_create (shm_name, SHM_SIZE);
shm_addr[0] = flags; // make sure it's 0;
}
extern int
main (int argc, char * argv[])
{
int rtnval;
#ifdef VERBOSE
printf ("Verbose output\n");
#endif
// Create a shared memory.
shm_addr = my_shm_create (shm_name, SHM_SIZE);
printf ("\nShared memory name '%s' is created. \n\n", shm_name);
set_turn(0);
wait_for_turn(0);
printf ("1\n");
set_turn(1);
wait_for_turn(0);
printf ("3\n");
set_turn(1);
wait_for_turn(0);
printf ("5\n");
set_turn(1);
wait_for_turn(0);
// Close the shared memory
printf ("\nCalling close(%#x)", shm_fd);
rtnval = close (shm_fd);
if (rtnval != 0)
{
perror ("ERROR: close() failed");
}
printf (" -> returned %d\n", rtnval);
shm_fd = -1;
// Unlink the shared memory so it can be removed (reference counting)
printf ("Calling shm_unlink('%s')", shm_name);
rtnval = shm_unlink (shm_name);
if (rtnval != 0)
{
perror ("ERROR: shm_unlink() failed");
}
printf (" -> returned %d\n", rtnval);
// Close the program
printf ("\nBye bye. Hope to see you soon.\n");
return 0;
}
void main(void) {
int * flag = (int *)my_shm_create("h_sync", sizeof(int));
*flag = 0;
int i = 1;
for (; i < 6; i+=2) {
while (*flag != 0) {
}
printf("%i\n", i);
*flag = 1;
}
while (*flag != 0) {} //wait for exit
}
