C语言日志打印并分包

    fp = fopen("log.log","w");

    /* ..... */

    fflush(fp);
    if ((log_siz) < ftell(fp))
    {
        rename("log.log","log.log2");
        freopen("log.log","w", fp);
    }
    fprintf(fp, "456");
    
    /* ..... */
    fclose(fp);