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gdb provides values it obtains from the inferior program in
an object of type gdb.Value
. gdb uses this object
for its internal bookkeeping of the inferior's values, and for
fetching values when necessary.
Inferior values that are simple scalars can be used directly in
Python expressions that are valid for the value's data type. Here's
an example for an integer or floating-point value some_val
:
bar = some_val + 2
As result of this, bar
will also be a gdb.Value
object
whose values are of the same type as those of some_val
.
Inferior values that are structures or instances of some class can
be accessed using the Python dictionary syntax. For example, if
some_val
is a gdb.Value
instance holding a structure, you
can access its foo
element with:
bar = some_val['foo']
Again, bar
will also be a gdb.Value
object.
For pointer data types, gdb.Value
provides a method for
dereferencing the pointer to obtain the object it points to.
This method returns a new
gdb.Value
object whose contents is the object pointed to by the pointer. For example, iffoo
is a C pointer to anint
, declared in your C program asint *foo;then you can use the corresponding
gdb.Value
to access whatfoo
points to like this:bar = foo.dereference ()The result
bar
will be agdb.Value
object holding the value pointed to byfoo
.