Im trying to add semaphores to syncronize my swimmill file , fish file and pellet file. I set up to create a semaphore with semget and initailise with semget. Im not sure if my semop is working. The three files are sharing memory and are out of sync. Below are all three files

/* The swim mill creates pellet and fish process by forking them as children and using shared memory to store the fish position and pallet position. it displays the swim_mill by checking the shared memory's updated position. The swim_mill also handles signals to begin aborting and clean up. */

#include #include #include #include #include #include #include #include

//signal flag int signalFlag = 1;

//test check void printMem(char * mem);

//signal handler to abort and kill processes void sighandler(int signum);

int main(int argc, char *argv[]) { int shmid;// char grid[10][10]; int fish; int timer = 0; int pelletID[18];

//kill processes handler signal(SIGINT, sighandler);

/* * Create the segment. */ if ((shmid = shmget(ftok("swim.txt", 'R'), sizeof(char[22]), IPC_CREAT|0660)) == -1){ perror("could not create memory segment"); }

/* * Now we attach the segment to our data space.mget. */ // Attach the shared memory segment. Exit on error. char *dataptr = shmat(shmid, NULL, 0);

//initializing to -1 for(int i = 1; i < 22; i++){ dataptr[i] = -1; }

//initializing pelletId for(int i = 0; i < 18; i++){ pelletID[i] = 0; } //initializing fish to be in middle position dataptr[0] = 94; //# of processe dataptr[21] = 2; printMem(dataptr); //create FISH child fish = fork();

//check creation of child if(fish == -1){ perror("fish creation unsuccesful "); }else if(fish == 0){

//execv(path name of file to be executed, //Array of pointer to argument. //Loads and executes a new child process execv("FISH",NULL); } //incrermenter int idIndex = 0;

while(timer <= 30){

//create second child pellet if(dataptr[21] < 20) { dataptr[21]++; pelletID[idIndex] = fork(); //check creation of child if(pelletID[idIndex] == -1){ perror("pellet creation unsuccesful "); }else if(pelletID[idIndex] == 0){ //Loads and executes a new child process execv("pellet",NULL); } idIndex++; }

//Displays the SWIMMILL, fish position, and pellet position. for(int i =0; i<10; i++){ for(int j = 0; j<10; j++){ grid[i][j] = '~';//water for(int k = 1; k < 10; k++) { if (dataptr[k] > -1 && dataptr[k] < 100) grid[dataptr[k]/10][dataptr[k]%10] = 'p';//display pellet } grid[dataptr[0]/10][dataptr[0]%10] = 'f';//display fish printf("%c", grid[i][j]);//display

} printf(" "); } //killed if(signalFlag == 0){ break; } sleep(1);

//prints out array in console, //printMem(dataptr); timer++; printf("Timer: %d ", timer); }//end of while loop //If signal handler is access if(signalFlag == 0){ //kill pellet process kill(fish, SIGINT); for(int j = 0; j< 18; j++){ if(pelletID[j] != 0){ kill(pelletID[j], SIGINT); } } } else { //kill fish printf("BEGIN SLAUGHTER!!!! "); printf("killing Fish! "); kill(fish, SIGUSR1);

//kill pellet process for(int j = 0; j< 18; j++){ if(pelletID[j] != 0){ printf("Killing pellets! %d ", pelletID[j]); kill(pelletID[j], SIGUSR1); } } } //goest to sleep and waits 10 seconds sleep(10);

shmdt(dataptr);//clean up data detach

//Delete shared memory shmctl(shmid,IPC_RMID,NULL);

return 0; }

//signal handler to kill process void sighandler(int signum){ if(signum == SIGINT){ signalFlag = 0; } }

//array check void printMem(char * mem) { for(int i = 0; i < 22; i++) printf("[%d]",mem[i]); printf(" "); }

//Author Jesus Vargas //Oct 26, 2017

/* * FISH process's job is to attacche to shared memory, find Manhattan distance from fish to pallet * and move towards the best lane. when it receives sigal or abort signal, it breaks out and cleans up * memory where fish was storing postions. */

#include #include #include #include #include #include #include

//signal flag int signalFlag = 1;

//pointer to shared memory segment char *dataptr;

//signal handler to abort and kill processes void sighandler(int signum);

int main(int argc, char *argv[]) { int shmid; //kill processes handler signal(SIGINT, sighandler); //abort and kill processes signal(SIGUSR1, sighandler); /* * allocate the segment. */ //location, size, permissions if ((shmid = shmget(ftok("swim.txt", 'R'), sizeof(char[11]), IPC_CREAT|0660)) == -1) { perror("Did not allocate segment"); }

// Attach the shared memory segment. Exit on error. dataptr = shmat(shmid, NULL, 0);

/*while loop is used to calculate fish to pellet position in order for the fish to move to the nearest pellets lane */ while(1){ //mimimum lane int min = 400; //lane that neares pellet is in int bestLane = 0; //Manhattan distance calculations of fish to pellet Manhattan distance for(int k = 1; k < 11; k++) { if (dataptr[k] > -1 && dataptr[k] < 100){ int calc = abs((dataptr[0]/10) - (dataptr[k]/10)) + abs((dataptr[0]%10) - (dataptr[k]%10)); if(calc < min){ min = calc; bestLane = dataptr[k]%10; } } } //fish moves towards pellet if(bestLane < dataptr[0]%10){ dataptr[0] -= 1; }else if(bestLane > dataptr[0]%10 ){ dataptr[0] += 1; } //abort and display id if(signalFlag == 0){ printf("Sigint received aborting fish: %d ", getpid()); break; } //put fish process to sleep sleep(1); } //clean up shmdt(dataptr); return 0; }

//signal handler to abort and kill process void sighandler(int signum){ if(signum == SIGINT){ signalFlag = 0; } else if(signum == SIGUSR1){ shmdt(dataptr); printf("poor fishy is dead!!"); exit(1); } }

/* * Pellet process handles the randomized postion of where the pellets will be dropped in swim_mill by * randomizing a position and storing it in dataptr where its initialized to -1. * while loop is in charge of moving the pellet down the swimmill. there are also signal handlers to * abort and clean up that uses */

#include #include #include #include #include #include #include #include

//signal flag int signalFlag = 2;

//pointer to shared memory segment char *dataptr;

//signal handler to abort and kill processes void sighandler(int signum);

int main(int argc, char *argv[]) { int shmid; //kill processes handler signal(SIGINT, sighandler);

//abort and kill processes signal(SIGUSR1,sighandler);

/* * allocate the segment. */ //location, size, permissions if ((shmid = shmget(ftok("swim.txt", 'R'), sizeof(char[11]), IPC_CREAT|0660)) == -1) { perror("Did not allocate segment"); } // Attach the shared memory segment. Exit on error. dataptr = shmat(shmid, NULL, 0);

//randomizing pallet srand(time(0));

//incrementer int i = 1; //takes care of randomizing pellet in position where dataptr is -1 for(; i < 21; i++){ if(dataptr[i] == -1){ //random pellet dataptr[i] = rand()%10 - 10; break; } } /*while loop finds pellet position in shared memory, *and updates pellet so it can move down the stream mill. *Once the pellet reaches the bottom row, the fish will eat it * or miss it. */ while(1){ //pallet moves down if (dataptr[i] < 90){ dataptr[i] += 10; } else {//pallet leaves swim_mill if(dataptr[i] == dataptr[0]){ printf("chomp pellet ID: %d Position: %d ", getpid(),dataptr[i]); dataptr[i] = -1; break; } else { printf("pellet missed pellet ID: %d Position: %d ", getpid(),dataptr[i]); dataptr[i] = -1; break; } } //abort and kill process if(signalFlag == 0){ printf("Sigint received aborting pellet: %d ", getpid()); break; } if(signalFlag == 1){ break; }

//put pellet process to sleep sleep(1); }//end of while loop //print out pellet id printf("pellet ded %d ", getpid());

dataptr[21]--;

//clean up shared memory detach shmdt(dataptr); return 0; }//end of main

//signal handler to abort and kill process void sighandler(int signum){ if(signum == SIGINT){ signalFlag = 0; } else if(signum == SIGUSR1){ signalFlag = 1; } }