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How do I get the path of the current executed file in Python?

This may seem like a newbie question, but it is not. Some common approaches don't work in all cases:

sys.argv[0]

This means using path = os.path.abspath(os.path.dirname(sys.argv[0])), but this does not work if you are running from another Python script in another directory, and this can happen in real life.

__file__

This means using path = os.path.abspath(os.path.dirname(__file__)), but I found that this doesn't work:

py2exe doesn't have a __file__ attribute, but there is a workaround

When you run from IDLE with execute() there is no __file__ attribute

Mac OS X v10.6 (Snow Leopard) where I get NameError: global name '__file__' is not defined

Related questions with incomplete answers:

Find path to currently running file

Path to current file depends on how I execute the program

How can I know the path of the running script in Python?

Change directory to the directory of a Python script

I'm looking for a generic solution, one that would work in all above use cases.

Update

Here is the result of a testcase:

Output of python a.py (on Windows)

a.py: __file__= a.py
a.py: os.getcwd()= C:\zzz

b.py: sys.argv[0]= a.py
b.py: __file__= a.py
b.py: os.getcwd()= C:\zzz

a.py

#! /usr/bin/env python
import os, sys

print "a.py: sys.argv[0]=", sys.argv[0]
print "a.py: __file__=", __file__
print "a.py: os.getcwd()=", os.getcwd()
print

execfile("subdir/b.py")

File subdir/b.py

#! /usr/bin/env python
import os, sys

print "b.py: sys.argv[0]=", sys.argv[0]
print "b.py: __file__=", __file__
print "b.py: os.getcwd()=", os.getcwd()
print

tree

C:.
|   a.py
\---subdir
        b.py

A
ArtOfWarfare

First, you need to import from inspect and os

from inspect import getsourcefile
from os.path import abspath

Next, wherever you want to find the source file from you just use

abspath(getsourcefile(lambda:0))

Best answer. Thank you.
Great answer. Thanks. It also seems to also be the shortest and most portable (running on different os-es) answer and doesn't encounter problems such as NameError: global name '__file__' is not defined (another solution caused this).
Another possibility which is equally short: lambda:_. It worked for me - not sure it'll always work. lambda:0 probably runs faster by some immeasurably small amount (or maybe not so small... might be a load immediate or something even faster for 0 vs a load global for _?) Debatable whether it's cleaner or easier to read or even more clever/obscure.
As with almost every proposal I have tried, this just returns the cwd for me, not the directory file I am running (debugging).
@James - This code goes in the file you're running... running getsourcefile(lambda:0) will be meaningless and just return None if you try running it at an interactive prompt (since the lambda won't be in any source file.) If you want to know where another function or object is coming from in an interactive environment, maybe abspath(getsourcefile(thatFunctionOrObject)) will be more helpful for you?
D
Daniel Stutzbach

You can't directly determine the location of the main script being executed. After all, sometimes the script didn't come from a file at all. For example, it could come from the interactive interpreter or dynamically generated code stored only in memory.

However, you can reliably determine the location of a module, since modules are always loaded from a file. If you create a module with the following code and put it in the same directory as your main script, then the main script can import the module and use that to locate itself.

some_path/module_locator.py:

def we_are_frozen():
    # All of the modules are built-in to the interpreter, e.g., by py2exe
    return hasattr(sys, "frozen")

def module_path():
    encoding = sys.getfilesystemencoding()
    if we_are_frozen():
        return os.path.dirname(unicode(sys.executable, encoding))
    return os.path.dirname(unicode(__file__, encoding))

some_path/main.py:

import module_locator
my_path = module_locator.module_path()

If you have several main scripts in different directories, you may need more than one copy of module_locator.

Of course, if your main script is loaded by some other tool that doesn't let you import modules that are co-located with your script, then you're out of luck. In cases like that, the information you're after simply doesn't exist anywhere in your program. Your best bet would be to file a bug with the authors of the tool.


I mention that on OS 10.6 I get NameError: global name '__file__' is not defined using file and this is not inside the IDLE. Think that __file__ is defined only inside modules.
@Sorin Sbarnea: I updated my answer with how I get around that.
Thanks, but in fact the problem with missing __file__ had nothing to do with Unicode. I don't know why __file__ is not defined but I'm looking for a generic solution this will work an all cases.
Sorry this is not possible in all cases. For example I try to do this in waf.googlecode.com from inside a wscript file (python). These files are executed but they are not modules and you cannot made them modules (they can be any any subdirectory from the source tree).
Won't that give you the location of some_path/module_locator.py instead?
P
Peter Mortensen

This solution is robust even in executables:

import inspect, os.path

filename = inspect.getframeinfo(inspect.currentframe()).filename
path     = os.path.dirname(os.path.abspath(filename))

This should be the correct answer. This works even in entry_point: console_script, but none of the other answers.
just gets cwd()
@eric: Point being?
@PeterMortensen file being run is often not in cwd()
P
Peter Mortensen

I was running into a similar problem, and I think this might solve the problem:

def module_path(local_function):
   ''' returns the module path without the use of __file__.  Requires a function defined
   locally in the module.
   from http://stackoverflow.com/questions/729583/getting-file-path-of-imported-module'''
   return os.path.abspath(inspect.getsourcefile(local_function))

It works for regular scripts and in IDLE. All I can say is try it out for others!

My typical usage:

from toolbox import module_path
def main():
   pass # Do stuff

global __modpath__
__modpath__ = module_path(main)

Now I use _modpath_ instead of _file_.


According to the PEP8 coding style guide, one should never create names with double leading and trailing underscores -- so __modpath__ should be renamed. You also probably don't need the global statement. Otherwise +1!
Actually you can define the local function right in the call to module_path(). i.e. module_path(lambda _: None) which doesn't depend on the other contents of the script it is in.
@martineau: I took your suggestion of lambda _: None and have used it for nearly the past two years, but just now I discovered I could condense it down to just lambda:0. Is there any particular reason you suggested the form you did, with an ignored argument of _, instead of with no argument at all? Is there something superior about None prefixed with a space rather than just 0? They're both equally cryptic, I think, just one is 8 characters long while the other is 14 characters long.
@ArtOfWarfare: The difference between the two is that lambda _: is a function that takes one argument and lambda: is one that doesn't take any. It doesn't matter since the function is never called. Likewise it doesn't matter what return value is used. I guess I chose None because at the time it seemed to indicate it was a do-nothing, never-to-be-called function better. The space in front of it is optional and again there only for improved readability (always trying to follow PEP8 is habit-forming).
@martineau: It's obviously an abuse of lambda though, using it for something it was never meant to do. If you were to follow PEP8, I think the right content for it would be pass, not None, but it's not valid to put a statement in a lambda, so you have to put in something with a value. There's a few valid 2 character things you could put in, but I think the only valid single character things you can put in are 0-9 (or a single character variable name assigned outside the lambda.) I figure 0 best indicates the nothingness of 0-9.
d
dgb

You have simply called:

path = os.path.abspath(os.path.dirname(sys.argv[0]))

instead of:

path = os.path.dirname(os.path.abspath(sys.argv[0]))

abspath() gives you the absolute path of sys.argv[0] (the filename your code is in) and dirname() returns the directory path without the filename.


C
Community

The short answer is that there is no guaranteed way to get the information you want, however there are heuristics that work almost always in practice. You might look at How do I find the location of the executable in C?. It discusses the problem from a C point of view, but the proposed solutions are easily transcribed into Python.


Hello, my flag was declined so I've now started a discussion on meta: meta.stackoverflow.com/questions/277272/…
There are simple working answers already on this page however. My solution works well: stackoverflow.com/a/33531619/3787376.
E
Edward

See my answer to the question Importing modules from parent folder for related information, including why my answer doesn't use the unreliable __file__ variable. This simple solution should be cross-compatible with different operating systems as the modules os and inspect come as part of Python.

First, you need to import parts of the inspect and os modules.

from inspect import getsourcefile
from os.path import abspath

Next, use the following line anywhere else it's needed in your Python code:

abspath(getsourcefile(lambda:0))

How it works:

From the built-in module os (description below), the abspath tool is imported.

OS routines for Mac, NT, or Posix depending on what system we're on.

Then getsourcefile (description below) is imported from the built-in module inspect.

Get useful information from live Python objects.

abspath(path) returns the absolute/full version of a file path

getsourcefile(lambda:0) somehow gets the internal source file of the lambda function object, so returns '' in the Python shell or returns the file path of the Python code currently being executed.

Using abspath on the result of getsourcefile(lambda:0) should make sure that the file path generated is the full file path of the Python file.
This explained solution was originally based on code from the answer at How do I get the path of the current executed file in Python?.


yeah I just came up with the same solution... way better than the answers that just say it can't reliably be done... unless the question isn't asking what I think it is...
P
Peter Mortensen

This should do the trick in a cross-platform way (so long as you're not using the interpreter or something):

import os, sys
non_symbolic=os.path.realpath(sys.argv[0])
program_filepath=os.path.join(sys.path[0], os.path.basename(non_symbolic))

sys.path[0] is the directory that your calling script is in (the first place it looks for modules to be used by that script). We can take the name of the file itself off the end of sys.argv[0] (which is what I did with os.path.basename). os.path.join just sticks them together in a cross-platform way. os.path.realpath just makes sure if we get any symbolic links with different names than the script itself that we still get the real name of the script.

I don't have a Mac; so, I haven't tested this on one. Please let me know if it works, as it seems it should. I tested this in Linux (Xubuntu) with Python 3.4. Note that many solutions for this problem don't work on Macs (since I've heard that __file__ is not present on Macs).

Note that if your script is a symbolic link, it will give you the path of the file it links to (and not the path of the symbolic link).


G
Gavriel Cohen

You can use Path from the pathlib module:

from pathlib import Path

# ...

Path(__file__)

You can use call to parent to go further in the path:

Path(__file__).parent

This answer uses the __file__ variable which can be unreliable (isn't always the full file path, doesn't work on every operating system etc.) as StackOverflow users have often mentioned. Changing the answer to not include it will cause less problems and be more cross-compatible. For more information, see stackoverflow.com/a/33532002/3787376.
@mrroot5 Ok, so delete your comment please.
P
Papershine

Simply add the following:

from sys import *
path_to_current_file = sys.argv[0]
print(path_to_current_file)

Or:

from sys import *
print(sys.argv[0])

A
Alex Cohn

If the code is coming from a file, you can get its full name

sys._getframe().f_code.co_filename

You can also retrieve the function name as f_code.co_name


T
ThienSuBS

The main idea is, somebody will run your python code, but you need to get the folder nearest the python file.

My solution is:

import os
print(os.path.dirname(os.path.abspath(__file__)))

With os.path.dirname(os.path.abspath(__file__)) You can use it with to save photos, output files, ...etc


An explanation would be in order. E.g., what is the idea/gist? Please respond by editing (changing) your answer, not here in comments (without "Edit:", "Update:", or similar - the answer should appear as if it was written today).
M
Mohamed.Abdo
import os
current_file_path=os.path.dirname(os.path.realpath('__file__'))

This does not make sense. First, '__file__' should not be a string, second, if you did __file__, this would only work for the file that this line of code is in, and not the file that is executed?
An explanation would be in order. E.g., what is the idea/gist? Please respond by editing (changing) your answer, not here in comments (without "Edit:", "Update:", or similar - the answer should appear as if it was written today).