You can implement new convenience functions (see Convenience Vars)
in Python. A convenience function is an instance of a subclass of the
The initializer for
Function registers the new function with
GDB. The argument name is the name of the function,
a string. The function will be visible to the user as a convenience
variable of type
internal function, whose name is the same as
the given name.
The documentation for the new function is taken from the documentation string for the new class.
When a convenience function is evaluated, its arguments are converted
to instances of
gdb.Value, and then the function’s
invoke method is called. Note that GDB does not
predetermine the arity of convenience functions. Instead, all
available arguments are passed to
invoke, following the
standard Python calling convention. In particular, a convenience
function can have default values for parameters without ill effect.
The return value of this method is used as its value in the enclosing
expression. If an ordinary Python value is returned, it is converted
gdb.Value following the usual rules.
The following code snippet shows how a trivial convenience function can be implemented in Python:
class Greet (gdb.Function): """Return string to greet someone. Takes a name as argument.""" def __init__ (self): super (Greet, self).__init__ ("greet") def invoke (self, name): return "Hello, %s!" % name.string () Greet ()
The last line instantiates the class, and is necessary to trigger the
registration of the function with GDB. Depending on how the
Python code is read into GDB, you may need to import the
gdb module explicitly.
Now you can use the function in an expression:
(gdb) print $greet("Bob") $1 = "Hello, Bob!"