int main(){
key_t key = ftok("file1.c", 1);
int semid = binary_semaphore_allocation(key, 0666 | IPC_CREAT);
binary_semaphore_initialize(semid);
binary_semaphore_take(semid);
printf("pr1: proc1 took the semaphore\n");
sleep(20);
binary_semaphore_free(semid);
printf("pr1: proc1 release the semaphore\n");
exit(0);
}
int main(){
key_t key = ftok("file1.c", 1);
int semid = binary_semaphore_allocation(key, 0666 | IPC_CREAT);
if (semid > 0) {
printf("pr2: Try take the sem\n");
binary_semaphore_take(semid);
printf("pr2: Yeeeh, we have taken it!\n");
binary_semaphore_free(semid);
printf("pr2: And released....\n");
exit(0);
}
printf("pr2: Unable to get sem id\n");
exit(1);
}
int main() {
char buf[BUF_SIZE];
int nread;
int flag = 0;
int nwrite;
int fdin,fdout;
int shmid;
const int shared_segment_size = BUF_SIZE + 1;
char* shared_memory;
key_t key = ftok("prog1.c", 1);
key_t keySem = ftok("tdf", 1);
key_t keySem1 = ftok("file", 1);
key_t keySem2 = ftok("rgv", 1);
int semid = binary_semaphore_allocation(keySem, 0666|IPC_CREAT);
printf("semid: %d\n ",semid);
int semid1 = binary_semaphore_allocation(keySem1, 0666|IPC_CREAT);
printf("semid1: %d\n ",semid1);
int semid2 = binary_semaphore_allocation(keySem2, 0666|IPC_CREAT);
printf("semid2: %d\n ",semid2);
binary_semaphore_initialize(semid);
binary_semaphore_initialize(semid1);
binary_semaphore_initialize_0(semid2);
shmid = shmget(key, shared_segment_size, 0666| IPC_CREAT);
if (shmid < 0)
printf("Shared memory get fail\n");
shared_memory = shmat(shmid, 0, 0);
shared_memory = "4555";
shared_memory[4] = '\0';
binary_semaphore_free(semid2);
sleep(10);
binary_semaphore_deallocate(semid);
binary_semaphore_deallocate(semid1);
binary_semaphore_deallocate(semid2);
return 0;
shared_memory[BUF_SIZE+1] = '0';
fdin = open("100mb_file", O_RDONLY);
//fdout = open("file.out", O_RDWR|O_CREAT,
//S_IRUSR|S_IWUSR);
int i = 0;
while ((nread = read(fdin, buf, BUF_SIZE)) > 0) {
printf("nread after while: %d\n", nread);
binary_semaphore_take(semid1);
printf("Take sem1\n");
binary_semaphore_take(semid);
printf("Take sem\n");
printf("iter: %d\n", i++);
if (nread < BUF_SIZE) {
buf[nread] = '\0';
//printf("buf last sem = %s \n", buf);
//shared_memory[BUF_SIZE+1] = '1';
}
//write(fdout, buf, BUF_SIZE);
printf("BUF_SIZE+1 = %c\n", shared_memory[BUF_SIZE +1]);
printf("read: %d\n", nread);
strcpy(shared_memory, buf);
//sleep(5);
binary_semaphore_free(semid);
printf("Free sem\n");
binary_semaphore_free(semid2);
printf("Free sem2\n");
//if (flag)
//shared_memory[0] = '\0';
}
sleep(2);
if (shmdt(shared_memory) == -1)
printf("shmdt fail\n");
else
printf("shmdt success\n");
if (shmctl(shmid, IPC_RMID, 0) == -1)
printf("shmctl fail\n");
else
printf("shmctl success\n");
binary_semaphore_deallocate(semid);
binary_semaphore_deallocate(semid1);
binary_semaphore_deallocate(semid2);
close(fdin);
//close(fdout);
return 0;
}
