sem.c

Linux下的多线程编程

/* File sem.c */
#include
#include
#include
#define MAXSTACK 100
int stack[MAXSTACK][2];
int size=0;
sem_t sem;


/* READ FORM 1.dat*/
void ReadData1(void){
FILE *fp=fopen("1.dat","r");
while(!feof(fp)){
fscanf(fp,"%d %d",&stack[size][0],&stack[size][1]);
sem_post(&sem);
++size;
}
fclose(fp);
}


/*READ FORM 2.dat*/
void ReadData2(void){
FILE *fp=fopen("2.dat","r");
while(!feof(fp)){
fscanf(fp,"%d %d",&stack[size][0],&stack[size][1]);
sem_post(&sem);
++size;
}
fclose(fp);
}


/*wait buffer data*/
void HandleData1(void){
while(1){
sem_wait(&sem);
printf("Plus:%d+%d=%d\n",stack[size][0],stack[size][1],
stack[size][0]+stack[size][1]);
--size;
}
}
void HandleData2(void){
while(1){
sem_wait(&sem);
printf("Multiply:%d*%d=%d\n",stack[size][0],stack[size][1],
stack[size][0]*stack[size][1]);
--size;
}
}
int main(void){
pthread_t t1,t2,t3,t4;
sem_init(&sem,0,0);
pthread_create(&t1,NULL,(void *)HandleData1,NULL);
pthread_create(&t2,NULL,(void *)HandleData2,NULL);
pthread_create(&t3,NULL,(void *)ReadData1,NULL);
pthread_create(&t4,NULL,(void *)ReadData2,NULL);
/*wait forever*/
pthread_join(t1,NULL);
}