编辑：见下面我的回答
我对 Arduino 平台相当陌生，现在使用 AdaFruit 的 attiny85 (Trinket) 库创建一个 USB HID 项目。另请参阅我之前回答的有关此库选项的问题： Change/Override Trinket (attiny85) USB Identification name, device name
我对一个罕见的与 C 相关的限制感到困惑（另请参阅上面链接中回答的最新评论到上一个问题），即通过单独编译对二进制文件进行分离后期绑定。如果要更改 USB 设备的选项，则必须更改库本身，这对我来说有点奇怪，因为它是一个库。
例如，如果在加载库之前包含带有更改选项的头文件，则不会发生任何更改，因为库不知道它，因为它也必须包含在此库中。
示例：这不起作用：
#include "myUSBOptions.h"
#include "TrinketHidCombo.h"
另一种方法：
所以我需要为每个项目更改库本身，在这种情况下是usbconfig.h文件。这对我来说听起来有点愚蠢，因为它是一个库，可以被其他项目使用。这可能是 Adafruit 库中的设计错误，诸如 vendorname、devicename 等必须在此库之外是可选的，并且当库更新时，您的设置可能会被覆盖。而且...您需要为每个单独的项目再次编辑文件。
所以我想出了在文件中包含一个可选头文件的想法，usbconfig.h这只#include "user_usbconfig.h"需要一次更改。但这不是唯一的usbconfig.h文件，至少有三个版本可用！在项目目录中创建一个 user_usbconfig.h 文件，编写一个批处理文件以使其自动化并将其包含在项目目录中，以便在切换项目时只需单击它即可更改选项。
在 usbconfig.h 文件中添加的行：
.......
#include "cmdline_defs.h"
#ifndef __usbconfig_h_included__
#define __usbconfig_h_included__
#include "user_usbconfig.h" // <-- added this
.......
例如项目中包含的 user_usbconfig.h
/* DEVICE SETTINGS */
/* Version number of the device: Minor number first, then major number. */
#define USB_CFG_DEVICE_VERSION 0x00, 0x01
/* VENDOR_NAME
* These two values define the vendor name returned by the USB device. The name
* must be given as a list of characters under single quotes. The characters
* are interpreted as Unicode (UTF-16) entities.
* If you don't want a vendor name string, undefine these macros.
* ALWAYS define a vendor name containing your Internet domain name if you use
* obdev's free shared VID/PID pair. See the file USB-IDs-for-free.txt for
* details.
*/
#define USB_CFG_VENDOR_NAME 'm', 'y', 'C', 'o', 'm', 'p', 'a', 'n', 'y', 'n'
#define USB_CFG_VENDOR_NAME_LEN 10
/* DEVICE_NAME
* Same as above for the device name. If you don't want a device name, undefine
* the macros. See the file USB-IDs-for-free.txt before you assign a name if
* you use a shared VID/PID.
*/
#define USB_CFG_DEVICE_NAME 'm', 'y', 'D', 'e', 'v', 'i', 'c', 'e'
#define USB_CFG_DEVICE_NAME_LEN 8
/* SERIAL_NUMBER
* Same as above for the serial number. If you don't want a serial number,
* undefine the macros.
* It may be useful to provide the serial number through other means than at
* compile time. See the section about descriptor properties below for how
* to fine tune control over USB descriptors such as the string descriptor
* for the serial number.
*/
/*#define USB_CFG_SERIAL_NUMBER 'N', 'o', 'n', 'e' */
/*#define USB_CFG_SERIAL_NUMBER_LEN 0 */
示例源代码 myProject.ino，除了激活 USB 之外什么都不做：
#include "TrinketHidCombo.h"
void setup()
{
TrinketHidCombo.begin();
}
void loop() // Main program - main()
{
// do nothing, check if USB needs anything done
TrinketHidCombo.poll();
}
我创建的批处理文件，添加到项目目录中：
@echo off
rem ********************************************************
rem * setTrinketUSBLibraryOptions.bat *
rem * ---------------------------------------------------- *
rem * Author : Erwin Haantjes *
rem * Project : Arduino Trinket USB *
rem * Dev date : 11-06-2016 *
rem * Last changed : 11-06-2016 *
rem * What it do : 'Copy' (link) USB options project to *
rem * Trinket lib to make settings optional.*
rem * *
rem ********************************************************
rem *** Config parts that can be modified if required
SET ARDUINO_LIB_DIR=F:\Program Files\Arduino\DigiSpark\Digispark-Arduino-1.0.4\libraries
SET USER_HEADER_FILE=user_usbconfig.h
SET ATU_HEADER_FILE=usbconfig.h
SET ATU_DIRNAME1=TrinketHidCombo
SET ATU_DIRNAME2=TrinketKeyboard
SET ATU_DIRNAME3=TrinketMouse
SET ATU_HEADER_FILE1=%ARDUINO_LIB_DIR%\%ATU_DIRNAME1%\%ATU_HEADER_FILE%
SET ATU_HEADER_FILE2=%ARDUINO_LIB_DIR%\%ATU_DIRNAME2%\%ATU_HEADER_FILE%
SET ATU_HEADER_FILE3=%ARDUINO_LIB_DIR%\%ATU_DIRNAME3%\%ATU_HEADER_FILE%
SET ATU_USER_HEADER_FILE1=%ARDUINO_LIB_DIR%\%ATU_DIRNAME1%\%USER_HEADER_FILE%
SET ATU_USER_HEADER_FILE2=%ARDUINO_LIB_DIR%\%ATU_DIRNAME2%\%USER_HEADER_FILE%
SET ATU_USER_HEADER_FILE3=%ARDUINO_LIB_DIR%\%ATU_DIRNAME3%\%USER_HEADER_FILE%
rem *** START
echo.
echo.
echo Set Thrinket USB Library options to match your project
echo ------------------------------------------------------
echo.
if "@%1"=="@/?" goto USAGE
if "@%1"=="@-?" goto USAGE
goto INTRO
:USAGE
SET USAGEMODE=true
echo Created by Erwin Haantjes 2016
echo.
echo USAGE:
echo %0 [/?,/C,-?,-C]
echo.
echo SWITCHES:
echo - ? Shows this help
echo - C Use copy command instead of symlink to hardcopy the "%USER_HEADER_FILE%" to it's targets
echo.
:INTRO
rem *** WARNING and NOTICE
echo WARNING:
echo - This batch changes/symlink options to be able to config the Trinket USB Library by project easily. Run this file once each time you work on a project to be sure you are using the right settings.
echo - If a physical %USER_HEADER_FILE% file exists in the library directory, it will be deleted!
echo.
echo NOTICE:
echo - Each "%ATU_HEADER_FILE%" file in (parts/the) Trinket USB library must include the line: #include "%USER_HEADER_FILE%" at top of the file after #define __usbconfig_h_included__ .
echo - Once applying this 'patch', you can change USB settings in the "%USER_HEADER_FILE%" file in this directory on the fly without the need to run this batch again. Just compile it after a change and your changes will be 'visible'.
echo.
echo.
echo Library directory is set to:
echo %ARDUINO_LIB_DIR%
echo.
echo.
if "%USAGEMODE%"=="true" goto END
echo Do you want to continue? Press any key.
pause >NUL
echo.
rem *** Check destinations
if exist "%USER_HEADER_FILE%" goto NEXT1
goto ERROR_NO_USER_FILE
:NEXT1
if exist "%ATU_HEADER_FILE1%" goto NEXT2
goto ERROR_LIB_NOT_EXISTS
:NEXT2
if exist "%ATU_HEADER_FILE2%" goto NEXT3
goto ERROR_LIB_NOT_EXISTS
:NEXT3
if exist "%ATU_HEADER_FILE3%" goto NEXT4
goto ERROR_LIB_NOT_EXISTS
:NEXT4
goto APPLY
rem *** ERRORS
:ERROR_NO_USER_FILE
echo ERROR: Create a "%USER_HEADER_FILE%" in this directory first.
goto ABORTED
:ERROR_LIB_NOT_EXISTS
echo %ATU_HEADER_FILE1%
echo ERROR: Check the directory location match your Arduino IDE setup, see "ARDUINO_LIB_DIR" at top of this batch file. Check also if you have the Trinket USB Library currently installed.
goto ABORTED
:APPLY
echo All seems to be fine, applying patch (symlinks).....
echo Checking and removing target files....
if exist "%ATU_USER_HEADER_FILE1%" goto REMOVE1
goto APPLY_NEXT2
:REMOVE1
echo Remove symlink of "%ATU_USER_HEADER_FILE1%" ....
del "%ATU_USER_HEADER_FILE1%"
:APPLY_NEXT2
if exist "%ATU_USER_HEADER_FILE2%" goto REMOVE2
goto APPLY_NEXT3
:REMOVE2
echo Remove symlink of "%ATU_USER_HEADER_FILE2%" ....
del "%ATU_USER_HEADER_FILE2%"
:APPLY_NEXT3
if exist "%ATU_USER_HEADER_FILE3%" goto REMOVE3
goto APPLY_NEXT
:REMOVE3
echo Remove file/symlink of "%ATU_USER_HEADER_FILE3%" ....
del "%ATU_USER_HEADER_FILE3%"
:APPLY_NEXT
echo.
if "@%1"== "@/c" goto APPLY_COPY
if "@%1"== "@/C" goto APPLY_COPY
if "@%1"== "@-c" goto APPLY_COPY
if "@%1"== "@-C" goto APPLY_COPY
echo Applying symlinks....
mklink /H "%ATU_USER_HEADER_FILE1%" "%USER_HEADER_FILE%"
mklink /H "%ATU_USER_HEADER_FILE2%" "%USER_HEADER_FILE%"
mklink /H "%ATU_USER_HEADER_FILE3%" "%USER_HEADER_FILE%"
goto SUCCESS
:APPLY_COPY
echo Copy file(s)....
copy "%USER_HEADER_FILE%" "%ATU_USER_HEADER_FILE1%"
copy "%USER_HEADER_FILE%" "%ATU_USER_HEADER_FILE2%"
copy "%USER_HEADER_FILE%" "%ATU_USER_HEADER_FILE3%"
SET COPYMODE=true
goto SUCCESS
:ABORTED
echo Batch aborted due error.
goto END
:SUCCESS
echo.
echo SUCCESS!
echo NOTICE:
echo - Patch succesfully applied when no error is visible on screen.
if "%COPYMODE%"=="true" echo - Because you specify the copymode switch, you have to take care of updates yourself. Run this batch file again when you have changed USB settings.
:END
SET USAGEMODE=
SET COPYMODE=
echo.
echo Press any key to exit...
pause >NUL
:DIE
echo.
结论和问题：
尽管这种方法运行良好，但我仍然不满意，想知道是否有更简单的方法可以做到这一点，而无需更改库的任何代码行。一个更“即时”的解决方案，因此您不必考虑这一点以避免错误和其他令人头疼的问题。