写一个xv6复制文件的c语言程序

以下是一个简单的 xv6 复制文件的 C 语言程序：

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

#define BUFSIZE 512

int main(int argc, char *argv[]) {

    if (argc != 3) {
        fprintf(stderr, "Usage: %s source_file destination_file\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    int source_fd, dest_fd;
    ssize_t bytes_read, bytes_written;
    char buffer[BUFSIZE];

    source_fd = open(argv[1], O_RDONLY);
    if (source_fd == -1) {
        perror("open source file error");
        exit(EXIT_FAILURE);
    }

    dest_fd = open(argv[2], O_WRONLY | O_CREAT, 0644);
    if (dest_fd == -1) {
        perror("open destination file error");
        exit(EXIT_FAILURE);
    }

    while ((bytes_read = read(source_fd, buffer, BUFSIZE)) > 0) {
        bytes_written = write(dest_fd, buffer, bytes_read);
        if (bytes_written == -1) {
            perror("write error");
            exit(EXIT_FAILURE);
        }
    }

    if (bytes_read == -1) {
        perror("read error");
        exit(EXIT_FAILURE);
    }

    if (close(source_fd) == -1) {
        perror("close source file error");
        exit(EXIT_FAILURE);
    }

    if (close(dest_fd) == -1) {
        perror("close destination file error");
        exit(EXIT_FAILURE);
    }

    printf("File copied successfully.\n");
    exit(EXIT_SUCCESS);
}

注意：这个程序只是一个示例，可能并不完美，您可以根据实际需要进行修改。