pthread producer consumer problem
hi all,
I am learing pthreads. I am trying to implement producer/consumer(5producers,5consumers) problem with buffer size=10.
given below is the program written using pthreds. (os is redhat linux9)
Code:
#include<pthread.h>
int counter=0;
int max=10;
pthread_mutex_t counter_mutex= PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t condp_mutex= PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t condc_mutex= PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t condVarProd= PTHREAD_COND_INITIALIZER;
pthread_cond_t condVarCons= PTHREAD_COND_INITIALIZER;
void *prodfun();
void *consfun();
main()
{
pthread_t prothr[10],conthr[10];
int i;
for(i=0; i<5; i++)
{
pthread_create(&prothr[i],NULL,&prodfun,NULL);
pthread_create(&conthr[i],NULL,&consfun,NULL);
}
for(i=0; i<5; i++)
{
pthread_join(prothr[i],NULL);
pthread_join(conthr[i],NULL);
}
}
void * prodfun()
{
while(1)
{
pthread_mutex_lock(&condp_mutex);
while(counter>=10)
{
{
pthread_cond_wait(&condVarProd,&condp_mutex);
}
}
pthread_mutex_unlock(&condp_mutex);
//pthread_mutex_lock(&counter_mutex);
counter++;
pthread_cond_signal(&condVarCons);
printf("I am producer %ld counter value=%d\n",pthread_self(),counter);
pthread_mutex_unlock(&condp_mutex);
//pthread_mutex_unlock(&counter_mutex);
//if(counter==5)
//sleep(1);
}
}
void * consfun()
{
while(1)
{
sleep(1);
pthread_mutex_lock(&condc_mutex);
while(counter<=0)
{
pthread_cond_signal(&condVarProd);
pthread_cond_wait(&condVarCons,&condc_mutex);
}
// pthread_mutex_unlock(&condc_mutex);
// pthread_mutex_lock(&counter_mutex);
if(counter>0)
{
printf("I am consumer %ld counter value=%d \n",pthread_self(),counter);
counter--;
pthread_cond_signal(&condVarProd);
}
// pthread_mutex_unlock(&counter_mutex);
pthread_mutex_unlock(&condc_mutex);
}
}
Output is :
Code:
I am producer 1082338496 counter value=1
I am producer 1082338496 counter value=2
I am producer 1082338496 counter value=3
I am producer 1082338496 counter value=4
I am producer 1082338496 counter value=5
I am producer 1082338496 counter value=6
I am producer 1082338496 counter value=7
I am producer 1082338496 counter value=8
I am producer 1082338496 counter value=9
I am producer 1082338496 counter value=10
I am consumer 1090726976 counter value=10
I am consumer 1116941120 counter value=9
I am consumer 1133718080 counter value=8
I am consumer 1150495040 counter value=7
I am consumer 1167272000 counter value=6
I am producer 1082338496 counter value=6
I am producer 1082338496 counter value=7
I am producer 1082338496 counter value=8
I am producer 1082338496 counter value=9
I am producer 1082338496 counter value=10
I am consumer 1090726976 counter value=10
I am consumer 1116941120 counter value=9
I am consumer 1133718080 counter value=8
I am consumer 1150495040 counter value=7
I am consumer 1167272000 counter value=6
I am producer 1082338496 counter value=6
I am producer 1082338496 counter value=7
I am producer 1082338496 counter value=8
I am producer 1082338496 counter value=9
I am producer 1082338496 counter value=10
Once the producer gets control then consumer is not given control until couter value =10 or 1 or 6.
How to make the output more random so that the output should be more random than looking as a pattern???
Please help.
Thanks in advance......
