python - GDB:如何从内置 python 更改便利变量

Question

如何从其内置的 python 中为 gdb 便利变量 赋值？我认为它应该很简单，因为它在尝试实现用户定义的函数时自然会出现。但是我找不到任何东西。

更新:添加了一个简化的示例。不过，我的实际功能更为复杂。无论如何，将变量从 python 传输到 gdb 的方法会有很大帮助。

一个用法示例(achtung!——它会引发错误):

#accept a string, return it's lenght
define RetLenOfArg
  py arg0 = gdb.parse_and_eval("$arg0")
  set $Retrn = py len(arg0)
end

Answer 1

存在 gdb 的 python API 来获取/设置便利变量:来自 documentation

Function: gdb.convenience_variable (name) Return the value of theconvenience variable (see Convenience Vars) named name. name must be astring. The name should not include the ‘$’ that is used to mark aconvenience variable in an expression. If the convenience variabledoes not exist, then None is returned.

Function: gdb.set_convenience_variable (name, value) Set the value ofthe convenience variable (see Convenience Vars) named name. name mustbe a string. The name should not include the ‘$’ that is used to marka convenience variable in an expression. If value is None, then theconvenience variable is removed. Otherwise, if value is not agdb.Value (see Values From Inferior), it is is converted using thegdb.Value constructor.