linux c 编程实战

#include <stdlib.h>

void example() {
    int *ptr = (int *)malloc(sizeof(int));
    if (ptr == NULL) {
        // 处理内存分配失败的情况
        return;
    }
    // 使用ptr
    free(ptr);  // 确保在使用完后释放内存
}

#include <stdio.h>

void example() {
    FILE *file = fopen("example.txt", "r");
    if (file == NULL) {
        perror("Failed to open file");
        return;
    }
    char buffer[100];
    if (fgets(buffer, sizeof(buffer), file) != NULL) {
        printf("%s", buffer);
    }
    fclose(file);  // 确保文件在使用完后关闭
}

#include <pthread.h>

pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;

void* thread_func(void *arg) {
    pthread_mutex_lock(&mutex);
    // 访问共享资源
    pthread_mutex_unlock(&mutex);
    return NULL;
}

int main() {
    pthread_t thread1, thread2;
    pthread_create(&thread1, NULL, thread_func, NULL);
    pthread_create(&thread2, NULL, thread_func, NULL);
    pthread_join(thread1, NULL);
    pthread_join(thread2, NULL);
    return 0;
}