线程同步
7 #include<errno.h>
8 #include<pthread.h>
9 int counter = 0;
10 void *pd(void* arg)
11 {
12 int val,i;
13 for(i = 0;i < N ;i++)
14 {
15 val = counter;
16 printf("%x:%d\n",(unsigned int)pthread_self(),val+1 );
17 counter = val + 1;
18 usleep(10);
19 }
20
21 return NULL;
22 }
23 int main(int argc,char* argv[])
24 {
25 int a,b;
26 pthread_t ptid1,ptid2;
27 a = pthread_create(&ptid1,NULL,pd,NULL);
28 b = pthread_create(&ptid2,NULL,pd,NULL);
29 if(a != 0)
30 {
31 fprintf(stderr,"cannt accees%s\n",strerror(errno));
32 exit(1);
33 }
34 if(b != 0)
35 {
36 fprintf(stderr,"cannt accees%s\n",strerror(errno));
37 exit(1);
38 }
39
40 pthread_join(ptid1,NULL);
41 pthread_join(ptid2,NULL);
42 return 0;
43 }

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <fcntl.h>
#include <unistd.h>
#include <pthread.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <errno.h>
#define SPEED 5
typedef struct node{
int data;
struct node *next;
} node;
typedef struct {
struct node *head;
} List;
void list_init(List *list)
{
list->head = NULL;
}
void list_destroy(List *list)
{
struct node *n, *t;
n = list->head;
while(n) {
t = n->next;
free(n);
n = t;
}
}
static struct node * make_node(int data)
{
struct node *n;
n = malloc(sizeof(struct node));
n->data = data;
n->next = NULL;
return n;
}
void list_insert(List *list, int data)
{
struct node *n;
n = make_node(data);
n->next = list->head;
list->head = n;
}
int list_delete(List *list)
{
int data;
struct node *n;
while (! (n = list->head)) {
usleep(SPEED);
}
data = n->data;
list->head = n->next;
free(n);
return data;
}
void list_show(List *list)
{
struct node *n;
n = list->head;
while(n) {
printf("%d ", n->data);
n = n->next;
}
putchar('\n');
}
void * consumer(void *args)
{
List *list = (List *)args;
while(1) {
printf("Remove = %d", list_delete(list));
usleep(SPEED);
}
return NULL;
}
void * productor(void *args)
{
int i = 0;
List *list = (List *)args;
while(1) {
printf("Add = %d\n", i);
list_insert(list, i);
i ++;
usleep(1000);
}
return NULL;
}
#define NUM 2
int main(int argc, char *argv[])
{
int i, ret;
pthread_t ptid[NUM];
List list;
list_init(&list);
for (i = 0; i < NUM; i ++) {
ret = pthread_create(&ptid[i], NULL,
(i % 2 == 0)? productor : consumer, &list);
assert(ret == 0);
}
for (i = 0; i < NUM; i ++) {
pthread_join(ptid[i], NULL);
}
list_destroy(&list);
return 0;
}这还没懂

#include<stdio.h>
#include<errno.h>
#include<unistd.h>
#include<fcntl.h>
#include<stdlib.h>
#include<string.h>
#include<pthread.h>
#include<semaphore.h>
#define NUM 5
pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t mutex1[5];
char kxj[5] = {'A','B','C','D','E'};
int left[5] = {4,0,1,2,3};
int right[5] = {0,1,2,3,4};
void *pthreads(void *arg)
{
int i = (int) arg;
while(1)
{
usleep(10000);
if(EBUSY == pthread_mutex_trylock(&mutex1[left[i]]))
{
continue;
}
if(EBUSY == pthread_mutex_trylock(&mutex1[right[i]]))
{
pthread_mutex_unlock(&mutex1[left[i]]);
continue;
}
printf("%c eating use left %d right %d\n",kxj[i],left[i],right[i]);
usleep(1);
pthread_mutex_unlock(&mutex1[left[i]]);
pthread_mutex_unlock(&mutex1[right[i]]);
}
return (void*)i;
}
int main(int argc,char*argv[])
{
pthread_t pid[NUM];
int ret,i;
for(i = 0;i < NUM;i++)
{
ret = pthread_create(&pid[i],NULL,pthreads,(void*)i);
if(ret != 0)
{
fprintf(stderr,"cannt access %s\n",strerror(errno));
}
}
for(i = 0;i < NUM;i++)
{
pthread_join(pid[i],NULL);
}
return 0;
}