类似于如何将 GUD 断点键绑定更改为旧的，但我想绑定CTRL+x后跟SPACEto gud-break。
我的工作（嗯，这是一个黑客；继续阅读）是：
(define-key ctl-x-map " " 'gud-break)
但是ctl-x-map是一个类似于全局映射的全局变量。事实上，如果我切换到另一个 C++ 缓冲区并键入 Ch k Cx SPC，我会得到：
C-x SPC runs the command gud-break (found in global-map), which is an interactive compiled Lisp function.
It is bound to C-x SPC, C-x C-a C-b.
(gud-break ARG)
Set breakpoint at current line.
这意味着所有缓冲区的全局定义都发生了变化，这是不正确的 AFAIK。
有没有办法“插入”或以某种方式影响 Cx 的本地键映射，我相信这是gud-mode-map因为我希望该绑定不是对所有 C++ 缓冲区都是全局的。例如，CTRL+的全局绑定x后跟SPACEis rectangle-mark-mode。
是的，我意识到标准绑定是C-x C-a C-bfor gud-break，但那是要求 RSI。
更新#1
因为我需要本地键映射gud-mode-map，所以只有在我运行调试器时才需要激活它。就我而言，这是在 C++ 模式缓冲区中，但我的理解是，它gud-mode-map仅在调试会话期间在那些 C++ 模式缓冲区中变为活动状态，并在 gud 模式完成时从键绑定中删除。
更新#2
这不起作用：
(define-key gud-mode-map [(control x ?\ )] 'gud-break) ;; <-- gave "Two bases given in one event" error too.
(define-key gud-mode-map (kbd "C-x SPC") 'gud-break) ;; <-- this does not work either.
更新#3
define-key作为一个实验，我在我添加到的钩子中注释掉了我的绑定gud-gdb-mode-hook，重新运行 gdb，然后切换到 gud 缓冲区（不是 C++ 源文件）并输入C-h k C-x SPC我得到这个：
C-x SPC runs the command gud-break (found in gud-mode-map), which is
an interactive Lisp closure.
It is bound to <menu-bar> <debug> <break>, C-x SPC, C-c C-b, C-x C-a
C-b.
(gud-break ARG)
Set breakpoint at current line.
但是当我切换到 C++ 缓冲区时，该缓冲区也应该临时插入相同的绑定（当 gud 模式处于活动状态时），然后做同样的事情，我得到了这个：
C-x SPC runs the command rectangle-mark-mode (found in global-map),
which is an interactive autoloaded compiled Lisp function in
'rect.el'.
It is bound to C-x SPC.
(rectangle-mark-mode &optional ARG)
Toggle the region as rectangular.
Activates the region if needed. Only lasts until the region is deactivated.
切换回 gud 缓冲区，然后键入C-h m以下内容：
Debugger mode defined in 'gud.el':
Major mode for interacting with an inferior debugger process.
You start it up with one of the commands M-x gdb, M-x sdb, M-x dbx,
M-x perldb, M-x xdb, or M-x jdb. Each entry point finishes by executing a
hook; 'gdb-mode-hook', 'sdb-mode-hook', 'dbx-mode-hook',
'perldb-mode-hook', 'xdb-mode-hook', or 'jdb-mode-hook' respectively.
After startup, the following commands are available in both the GUD
interaction buffer and any source buffer GUD visits due to a breakpoint stop
or step operation:
C-x SPC sets a breakpoint at the current file and line. In the
GUD buffer, the current file and line are those of the last breakpoint or
step. In a source buffer, they are the buffer's file and current line.
...
注意C-x SPC上面的引用。就好像他们打算绑定C-x SPC但它不起作用，或者当进入 gud 模式时，某些东西阻止它在该缓冲区中正确绑定。