linux 嵌入式编程

#include <stdio.h>
#include <stdlib.h>

#define MEMORY_POOL_SIZE 1024

static char memory_pool[MEMORY_POOL_SIZE];
static size_t memory_used = 0;

void* my_malloc(size_t size) {
    if (memory_used + size > MEMORY_POOL_SIZE) {
        return NULL; // 内存不足
    }
    void* ptr = &memory_pool[memory_used];
    memory_used += size;
    return ptr;
}

void my_free(void* ptr) {
    // 简单的内存池管理，不实际释放内存
}

int main() {
    void* ptr = my_malloc(100);
    if (ptr == NULL) {
        printf("Memory allocation failed\n");
        return 1;
    }
    // 使用分配的内存
    my_free(ptr);
    return 0;
}

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

void* real_time_task(void* arg) {
    struct sched_param param;
    param.sched_priority = sched_get_priority_max(SCHED_FIFO);
    pthread_setschedparam(pthread_self(), SCHED_FIFO, &param);

    // 实时任务代码
    while (1) {
        // 执行实时任务
    }
    return NULL;
}

int main() {
    pthread_t thread;
    pthread_create(&thread, NULL, real_time_task, NULL);
    pthread_join(thread, NULL);
    return 0;
}

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

#define DEVICE_PATH "/dev/mydevice"

int main() {
    int fd = open(DEVICE_PATH, O_RDWR);
    if (fd == -1) {
        perror("Failed to open device");
        return 1;
    }

    // 操作设备
    write(fd, "Hello, Device!", 15);

    close(fd);
    return 0;
}