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

//static int a=4;

int a = 1;

void *create(void *arg)
{
    printf("new pthread ... \n");
    printf("a=%d  \n",a);  //此时打印a=1，如果将int a=5改为 a=5，则此处打印a=5

    return (void *)0;
}

int main(int argc,char *argv[])
{
    pthread_t tidp;
    int error;
    
    int a=5;

    printf("a = %d\n",a); //此时打印a=5 ，    
    //error=pthread_create(&tidp, NULL, create, NULL);

    if(error!=0)
    {
        printf("new thread is not create ... \n");
        return -1;
    }
    
    sleep(1);
    
    printf("new thread is created ... \n");
    return 0;
}