Am I right in assuming that the Python shell is coded in Python? If so, where, might one find the source code? If I wanted to write a shell program that did things differently, could I just copy the code to new_shell.py, make a few changes, and then set up a bash alias 'python'='python3 new_shell'?
There are various versions of Python. The most popular one is cpython, and the source code for that can be found here: cpython. If you want Python written in Python, check out PyPy.
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As we all know, usually Python projects exclusively run on the Python version (2 or 3) that they were made for.
However, when I come across Python projects, for example this one on GitHub, they almost never state the necessary Python version.
How do you know which Python you need to run the project?
Python doesn't support a means to determine this automatically.
You (the author of a python project) can make your python application friendly, as discussed here.
However, if the author didn't do that (and most don't) then you can only try and hope for the best, AFAIK.
I'm kinda new to scripting for IDA - nevertheless, I've written a complex script I need to debug, as it is not working properly.
It is composed of a few different files containing a few different classes.
Writing line-by-line in the commandline is not effective for obvious reasons.
Running a whole script from the File doesn't allow debugging.
Is there a way of using the idc, idautils, idaapi not from within IDA?
I've written the script on PyDev for Eclipse, I'm hoping for a way to run the scripts from within it.
A similar question is, can the api classes I have mentioned work on idb files without IDA having them loaded?
Thanks.
Now I may be wrong for I haven't written any IDA script for long time. But as far as I remember the answer to your first question is no. There is the part that loads the IDA script and prepare the whole environment so you could re implement it and create your own environment, however I would not recommend that.
What I can tell you is to consider running your script from command line if automation is what you are aiming for. IDA python (as well as any other IDA plugin) have a good support for running scripts from command line. For performance you can also run the TUI version of IDA.
There is also a hack for that enables you to launch a new python interpreter in the middle of the IDA script. It is useful for debugging a current state yet you will still need to edit the python file every time to launch the interpreter.
Here is the hack:
import code
all = globals()
all.update(locals())
code.interact(local = all)
Anyway - logs are good and debug prints are OK.
Good luck :)
We've just got a notice from one of our users that the latest version of WingIDE supports debugging of IDAPython scripts. I think there are a couple of other programs using the same approach (import a module to do RPC debugging) that might work.
Is there a way to get eclipse to read .pyc files?
I'm trying to avoid downloading an external program and I would rather not trust an on-line service.
There is no open-source/free decompiler for Python - just a "disassembler" (see the dis-module in the stdlib). Getting back from the Python Stack-VM-assembly (which is stored in .pyc-files) to working Python code is mostly easy, as the general structure of the code is preserved, even when using "-O".
For special case solutions (i.e., marshalling .pyc-s in the old [pre 2.3]-format), see the answer #FabioZadrozny linked, but especially when you're using Python >=2.5 to produce the .pyc-s, this will most probably not work, though, as a lot of opcodes have changed/been added.
I am trying to set up Python on Windows 7. I haven't used this language before so it seems strange to me.
I've downloaded lastest Python release 3.2.2 from official site and upadate path variable.
However I still can't even run simplest program ever like this :
print 'Hello, world!'
It says that there is a syntax error and the last character ' is highlighted with red.
I don't know if my path variable has been set properly. Here is where I installed Python :
C:\Software\Python32
So I added such a variable : var name = PYTHONPATH , var value = C:\Software\Python32\Lib
Is there something with auto-completion and with errors/warnings details ( which line, hint what can be wrong ), for example like Eclipse or NetBeans OR should I use this installed Python IDLE GUI for delevoping or stuff like NotePad++ ?
Actually what is this Python shell for ? - I know that I can type in some arithmetic operations here and I will get results, but is it used for something more advanced ? ( Is it used when I am writting something bigger ? )
Could someone describe simple way to write and execute a program ( or script I a total beginner so I don't really know what it is going on here ) ?
In Python 3.2 you have to use print in the below manner. The parentheses are mandatory. (print became a function in Python 3)
print('Hello World')
As Venk stated, the print statement in Python 2.x has been replaced with print() in 3.x, so your statement should read
print('Hello World')
Since you're new, here some things you should know about Python versions:
Python currently comes in two flavors: Python 2.x and Python 3.x.
Python 2.x has been in development since the late '90s, so most existing codebases, frameworks, and libraries are written in this flavor of Python. Each successive version is backwards compatible, so, for example, all code written in Python 2.4 can be run with Python 2.4+. Its current revision is 2.7.2, which was released last year.
Python 3.x is considered the "future" of Python, and purposefully breaks a lot of the conventions, such as the print statement, in favor of a clearer, more explicit language. Most libraries are working to port over to Python 3.x, but since there are extensive changes in the structure of the language, most library maintainers have not yet been able to release a Python 3.x compatible version with the full features of the Python 2.x version of the library.
If you're developing now, you should learn Python 2.x; otherwise, it's recommended you learn Python 3.x.
To answer your other questions:
Python's native IDLE is an excellent IDE, but if you're looking for something more advanced, you may want to try out Eclipse's PyDev extension or PyCharm. I personally prefer PyCharm, since it doesn't keep giving me errors when I'm importing/using nonstandard Python libraries/frameworks.
In addition, Python's shell is used to interpret Python scripts (in the background) and for interactive interpreting (i.e., quick and dirty testing), and can execute code you type into it. The latter, however, is not recommended, as a single syntax error in multiple lines of code can force you to retype all the lines to fix a single bug.
Furthermore, all Python scripts end in .py, so if you can see the file extensions, you can convert a text file into a Python script, and run from shell by typing python path/to/file.py. Note, however, that you still have to write a valid Python script, or it will not run.
I suggest A Byte of Python. It'll take you through install, REPL, syntax, and the std library.
The python shell is for entering code interactively.
Try the following: http://docs.python.org/tutorial/
I've been using Python on Windows 7 for 3 years now, and I strongly recommend Notepad++ as your editor/interpreter. It is ideal for people who want to play around with the language and are learning. Notepad++ can be customized for almost any language and is free for Windows. Follow this link
and take a look at how to conveniently use Notepad++ to execute Python scripts.
I am learning Python. My intentions are:
to write a webapp in Python/Django
create an android app (using Jython)
write some python scripts for unix box
I was under (incorrect) impression that because Python has been implemented in Java (Jython) and .NET (IronPython), I could simply write my Python code and run it through either interpreter/compiler.
I thought if I wrote a hello world in CPython and compiled it with Jython, I'd get Java bytecode. If I compliled it with IronPython, I'd get .NET bytecode.
But now it seems like regular Python code won't work with Jython compiler/interpreter. You've to import some fancy Java specific modules. So, that means, I would have to re-write my program for Java using Java modules/libraries.
Any tips on how to write my Python code so that it works everywhere? Web, Unix, Android.
NOTE: I don't want to have to learn Java.
Thanks
print 'Hello, World!'
This works just fine on any Python implementation worthy of the name. So will most other pure-Python code. Where it gets tricky is when using libraries, as Jython and IronPython are missing some standard library modules and don't support C extensions. Dealing with platform-specific code can also present some issues.
If you want your code to be portable, you need to remove as many dependencies as possible from the shared code. The standard library is generally OK (but not complete in either), and pure-Python external modules are generally OK if they only depend on other pure-Python modules.
If you do need to detect them, I believe the canonical checks are:
if os.name == 'java': # Jython
if sys.platform == 'cli': # IronPython
Neither Jython nor IronPython will produce programs that will run without Jython/IronPython being present. In principle it's possible, and it's even possible to compile a subset of Python to pure bytecode; the former requires linking in the Python engine, and the latter would require restricting what parts of Python you could use.
If someone were to provide this for IronPython I wouldn't turn it down, and I doubt the Jython team would either, but I'm not holding my breath. Either option is a lot of work.
Please be more specific about what you are trying to do. What is your regular Python code ? What does not work with it as you expected ?
According to the Jython FAQ, Jython is an implementation of the Python language. The same Python code should produce the same result on Jython or CPython.