pdb
The module pdb defines an interactive source code debugger for
Python programs. It supports setting breakpoints and single stepping
at the source line level, inspection of stack frames, source code
listing, and evaluation of arbitrary Python code in the context of any
stack frame. It also supports post-mortem debugging and can be called
under program control.
The debugger is extensible — it is actually defined as a class
Pdb. This is currently undocumented but easily understood by
reading the source. The extension interface uses the (also
undocumented) modules bdb and cmd.
Pdb
bdb
cmd
A primitive windowing version of the debugger also exists — this is
module wdb, which requires STDWIN (see the chapter on STDWIN
specific modules).
wdb
The debugger's prompt is ``(Pdb) ''.
Typical usage to run a program under control of the debugger is:
>>> import pdb
>>> import mymodule
>>> pdb.run('mymodule.test()')
> <string>(0)?()
(Pdb) continue
> <string>(1)?()
(Pdb) continue
NameError: 'spam'
> <string>(1)?()
(Pdb)
Typical usage to inspect a crashed program is:
>>> import pdb
>>> import mymodule
>>> mymodule.test()
Traceback (innermost last):
File "<stdin>", line 1, in ?
File "./mymodule.py", line 4, in test
test2()
File "./mymodule.py", line 3, in test2
print spam
NameError: spam
>>> pdb.pm()
> ./mymodule.py(3)test2()
-> print spam
(Pdb)
The module defines the following functions; each enters the debugger
in a slightly different way:
Subsections