How do I look up overloaded methods in GDB using the python interface?
I have a class which has several methods called 'el', one of which takes two ints. GDB is stopped at a breakpoint, with a member variable called _Dr in scope in the inferior process. I do this to get a Python gdb.Value object representing _Dr:
(gdb) python _Dr = gdb.parse_and_eval('_Dr')
Now I want to get the el(int,int) method:
(gdb) python el = _Dr['el']
Traceback (most recent call last):
File "<string>", line 1, in <module>
gdb.error: cannot resolve overloaded method `el': no arguments supplied
Error while executing Python code.
How do I tell it the types of the arguments to resolve the overload?
I've tried this:
(gdb) python el = _Dr['el(int,int)']
Traceback (most recent call last):
File "<string>", line 1, in <module>
gdb.error: There is no member or method named el(int,int).
Error while executing Python code.
and this:
(gdb) python el = _Dr['el', 'int', 'int']
Traceback (most recent call last):
File "<string>", line 1, in <module>
TypeError: Could not convert Python object: ('el', 'int', 'int').
Error while executing Python code.
and this:
(gdb) python el = _Dr['el(1,1)']
Traceback (most recent call last):
File "<string>", line 1, in <module>
gdb.error: There is no member or method named el(1,1).
Error while executing Python code.
What's the right way of doing this?
The best way to do this is to iterate over the fields of the type, looking for the one you want.
Something like:
for field in _Dr.type.fields():
if field.name == 'el':
... check field.type here ...
See the node "Types in Python" in the gdb manual for more details.
Related
I am trying to open and load pickle file but by two ways. But every time I am getting an error.
Request you to please help.
First way :
enron_data = pickle.load(open("D:/New/ud120-projects/final_project/final_project_dataset.pkl", "r"))
Error: Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: a bytes-like object is required, not 'str'
Second Way :
enron_data = pickle.load(open("D:/New/ud120-projects/final_project/final_project_dataset.pkl", "rb"))
Error : Traceback (most recent call last):
File "<stdin>", line 1, in <module>
_pickle.UnpicklingError: the STRING opcode argument must be quoted
Request you to please help
If you are on Windows you have to use a raw string and backslashes like this:
r'D:\path\to\your\file'
I'm on Debian 7.6. I installed python 2.7 and libguestfs0 and other packages that I need.
This is a sample code that I try to use guestfs, I enter these codes on debian terminal:
debian#debian$ python
>>> import guestfs
>>> g=guestfs.GuestFS (python_return_dict=True)
`Exception AttributeError: "GuestFS instance has no attribute '_o'" in <bound method GuestFS.__del__ of <guestfs.GuestFS instance at 0x203f908>>
ignored
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: __init__() got an unexpected keyword argument 'python_return_dict'`
I searched a lot but I can't find solution for this error.
Thanks
Why these below statements are giving error
>>> exec("x={}".format('b'))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<string>", line 1, in <module>
NameError: name 'b' is not defined
I need the result to be
x='b'
You should provide another pair of quotes
>>> exec("x={}".format("'b'"))
>>> x
'b'
Why?
When you write
exec("x={}".format('b'))
you are trying to write
x=b
obviously python doesn't know what b is unless you have defined it before.
Where as when you write
exec("x={}".format("'b'"))
It is same as
x='b'
I am trying to generate the help text at runtime and i am not able to use the pydoc command in Windows. When i type
>>> pydoc(atexit)
Traceback (most recent call last):
File "<console>", line 1, in <module>
NameError: name 'pydoc' is not defined
I have already set up the environment variables for pydoc.py file. C:\Python33\Lib\pydoc.py.
This also not works like it works for >>help('atexit')
>>> pydoc('atexit')
Traceback (most recent call last):
File "<console>", line 1, in <module>
NameError: name 'pydoc' is not defined
Whats the possible reason for it.
Updates:
>>> import pydoc
>>> pydoc(sys)
Traceback (most recent call last):
File "<console>", line 1, in <module>
TypeError: 'module' object is not callable
>>> pydoc('sys')
Traceback (most recent call last):
File "<console>", line 1, in <module>
TypeError: 'module' object is not callable
Like any library in Python, you need to import it before you can use it.
Edit What exactly are you trying to achieve? Modules are indeed not callable. pydoc.help is the function you want, although I don't really know why you need it, since as you note the standalone help function does the same thing already.
I'm trying to use PyKDE, PyKDE.kdecore.KStandardDirs to be precise. This method is called with two strings according to the documentation and according to the PyQt4 documentation, I can use standard Python strs instead of QString.
This doesn't work:
>> KStandardDirs.locate()("socket", "foo")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: KStandardDirs.locate(): not enough arguments
>>> KStandardDirs.locate("socket", "foo")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: KStandardDirs.locate(): argument 1 has unexpected type 'str'
I can't use QString either because it doesn't seem to exist:
>>> from PyQt4.QtCore import QString
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: cannot import name QString
>>> from PyQt4.QtCore import *
>>> QString
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'QString' is not defined
What am I doing wrong?
I suspect that PyKDE is not yet Python 3 ready, at least as far as that error message is concerned; try passing in a bytestring instead:
KStandardDirs.locate(b"socket", "foo")