Pthread 뮤텍스 -상호 배제 기법

뮤텍스 선언과 초기화

pthread_mutex_t muetex_lock=PTHREAD_MUTEX_INITIALIZER;

뮤텍스 락 걸기/풀기

int pthread_mutex_lock(pthread_mutex_t *mutex);

int pthread_mutex_unlock(pthread_mutex_t *mutex);

뮤텍스 파괴

int pthread_mutex_destroy(pthread_mutex_t* mutex);

pthread_mutex.c

#include <pthread.h>

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

pthread_mutex_t mutex_lock=PTHREAD_MUTEX_INITIALIZER;

int g_count;

void* t_function(void* data){

char* thread_name=(char*)data;

pthread_mutex_lock(&mutex_lock);

printf("%s start\n", thread_name);

for(int i=0;i<100000000;i++){

g_count++;

}

printf("%s, g_count=%d\n", thread_name, g_count);

pthread_mutex_unlock(&mutex_lock);

}

int main(void){

pthread_t p_thread1, p_thread2;

int status;

pthread_create(&p_thread1, NULL, t_function, (void*)"Thread 1");

pthread_create(&p_thread2, NULL, t_function, (void*)"Thread 2");

pthread_join(p_thread1, (void*)&status);

pthread_join(p_thread2, (void*)&status);

}

celina@ubuntuserver:~/celina/shell$ ./pthread_mutex2

Thread 2 start

Thread 2, g_count=100000000

Thread 1 start

Thread 1, g_count=200000000

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