typedef? struct ct_sum
{? ??
int? sum;
pthread_mutex_t lock;
}ct_sum;
void? * add1( void * cnt)
{
pthread_mutex_lock(&(((ct_sum*)cnt)->lock));
int? i;
for ( i=0;i<50;i++){
(*(ct_sum*)cnt).sum+=i;}
pthread_mutex_unlock(&(((ct_sum*)cnt)->lock));
pthread_exit(NULL);
return? 0;
}
void? * add2( void *cnt)
{
int? i;
cnt= (ct_sum*)cnt;
pthread_mutex_lock(&(((ct_sum*)cnt)->lock));
for ( i=50;i<101;i++)
{? ? (*(ct_sum*)cnt).sum+=i;
}
pthread_mutex_unlock(&(((ct_sum*)cnt)->lock));
pthread_exit(NULL);
return? 0;
}
int? main( void)
{? ? int? i;
pthread_t ptid1,ptid2;
int? sum=0;
ct_sum cnt;
pthread_mutex_init(&(cnt.lock),NULL);
cnt.sum=0;
pthread_create(&ptid1,NULL,add1,&cnt);
pthread_create(&ptid2,NULL,add2,&cnt);
pthread_mutex_lock(&(cnt.lock));
printf( "sum %d\n" ,cnt.sum);
pthread_mutex_unlock(&(cnt.lock));
pthread_join(ptid1,NULL);
pthread_join(ptid2,NULL);
pthread_mutex_destroy(&(cnt.lock));
return? 0;
}
