Thread-local storage (TLS)

#include<pthread.h>
#include<unistd.h>
#include<string.h>
#include <stdio.h>

__thread int var=1;

typedef struct context_t
{
  int p1;
  char name[256];
}context;

__thread  context ctx;

void  product(char *name)
{
   static  __thread int i = 0;
   printf("--->%s:%d\n",name, ++i);
}

void* worker1(void*arg);
void* worker2(void*arg);

int main()
{
    pthread_t pid1,pid2;
    memset(&ctx, 0, sizeof(context));
    ctx.p1 = 11;
    strcpy(ctx.name, "null");

    pthread_create(&pid1,NULL,worker1,NULL);
    pthread_create(&pid2,NULL,worker2,NULL);
    pthread_join(pid1,NULL);
    pthread_join(pid2,NULL);

    printf("exit, var:%d, p1:%d, name=%s \n",var,ctx.p1, ctx.name);

    return 0;
}
void* worker1(void* arg)
{
strcpy(ctx.name, "lilei");
ctx.p1=1;
printf("work1:%d \n", ++var);
printf("work1:%d, name=%s\n", ctx.p1, ctx.name);
product("work1");
}
void* worker2(void* arg)
{
sleep(5);
printf("work2:%d \n", ++var);
printf("work2:%d, name=%s\n", ctx.p1, ctx.name);
product("work2");
}

[root@localhost test]# gcc -lpthread -o test test.c 
[root@localhost test]# ./test 
work1:2 
work1:1, name=lilei
--->work1:1
work2:2 
work2:0, name=
--->work2:1
exit, var:1, p1:11, name=null