void initiate(char ** argv){
int key2 = ftok("makefile",'e');
//creating
if (strcmp(argv[1], "--create") == 0){
createsharedmem(key2);
createsem(key2);
createfile("story.txt");
printf("INITIATED\n");
}
//removing
else if (strcmp(argv[1], "--remove") == 0) {
//remove the shared memory (we need to remove pointers to memories separately or else shared memory will not disappear)
removesharedmem(key2);
//remove the semaphore
removesem(key2);
//display the file
if (filesize() >0){
int fd;
fd = open("story.txt", O_RDWR | O_APPEND, 0644);
write(fd, "\n",2);
}
//Display the full contents of the story
execlp("cat","cat","story.txt",NULL);
}
else{
printf("INVALID INPUT: Please run control with either '--create' or '--remove'.\n");//
}
}
int main (int argc,char* argv[])
{
//main ss
int semid,shmid;
char *shmaddr;
char write_str[SHM_SIZE];
memset(write_str,SHM_SIZE,'\0');
if ((shmid = createshm(".",'m',SHM_SIZE)) == -1) {
exit(-1);
}
if((shmaddr = shmat(shmid,(char*)0,0)) == (char*)-1)
{
cout << "shmat error" << endl;
}
if((semid =(createsem(".",'s',1,1)))==-1)
{
exit(-1);
}
while(1)
{
wait_sem(semid,0);
sem_P(semid,0);
cout << "writer:"<< "do something here" << endl;
fgets(write_str,1024,stdin);
int length = strlen(write_str);
write_str[len]='\0';
strncpy(shmaddr,write_str,len+1);
sleep(10);
}
return 0;
}
int diningphilosopher()
{
status= shmat(shmid, (void *)0, 0);
for(int i=0;i<N;i++)
{
createsem(i);
}
for(int i=0;i<N; i++)
{
// All the philosophers are thinking initially
status[i]=THINKING;
}
for(int i=0;i<N;i++)
{
int a =fork();
if(a!=0)
{
// I am in the parent
}
else
{
down(i);
philosopher(i);
printf("status of philosopher %d = %d\n", i+1, status[i]);
}
}
return 0;
} // end of dining philosopher function
