473,396 Members | 1,606 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,396 software developers and data experts.

__file__ vs __FILE__

I apologize in advance for coming at this from this angle but...

In PHP you have the __FILE__ constant which gives you the value of the
absolute path of the file you're in (as opposed to the main script
file.) With the function dirname, this makes it easy to get the
parent dir of a particular file from within that file:

$parent_dir = dirname(__FILE__);

I'm looking for the best way to accomplish this in Python. This seems
to work:

parent_dir = os.path.normpath(os.path.join(os.path.abspath(__fi le__),
'..'))

Can anyone confirm the reliability of this method or suggest a better
(one-line) method for accomplishing this?

Thanks,
Tom

Nov 3 '07 #1
10 12360
The __file__ attribute is present when you run a script from a file.
If you run from the interactive interpreter, it will raise a
NameError. Likewise, I believe that in earlier versions of Python
(2.1? Pre 2.2?) it was only set within imported modules. I've used the
'os.path.realpath(os.path.pardir)' construct in a couple of scripts
myself. That ought to work within the interactive interpreter.

Jeff

On Nov 2, 2007, at 11:21 PM, klenwell wrote:
I apologize in advance for coming at this from this angle but...

In PHP you have the __FILE__ constant which gives you the value of the
absolute path of the file you're in (as opposed to the main script
file.) With the function dirname, this makes it easy to get the
parent dir of a particular file from within that file:

$parent_dir = dirname(__FILE__);

I'm looking for the best way to accomplish this in Python. This seems
to work:

parent_dir = os.path.normpath(os.path.join(os.path.abspath(__fi le__),
'..'))

Can anyone confirm the reliability of this method or suggest a better
(one-line) method for accomplishing this?

Thanks,
Tom

--
http://mail.python.org/mailman/listinfo/python-list
Nov 3 '07 #2
Jeff McNeil wrote:
I've used the 'os.path.realpath(os.path.pardir)' construct in a
couple of scripts myself.
In Windows? Using Linux, this gives me "..".

I use os.path.dirname(os.path.abspath(__file__))
That ought to work within the interactive interpreter.
Why do you also enter that code in the interpreter? If it is in a
module, you should always be able to use __file__.

Regards,
Björn

--
BOFH excuse #238:

You did wha... oh _dear_....

Nov 3 '07 #3
On 3 Nov, 04:21, klenwell <klenw...@gmail.comwrote:
I apologize in advance for coming at this from this angle but...

In PHP you have the __FILE__ constant which gives you the value of the
absolute path of the file you're in (as opposed to the main script
file.) With the function dirname, this makes it easy to get the
parent dir of a particular file from within that file:

$parent_dir = dirname(__FILE__);

I'm looking for the best way to accomplish this in Python. This seems
to work:

parent_dir = os.path.normpath(os.path.join(os.path.abspath(__fi le__),
'..'))

Can anyone confirm the reliability of this method or suggest a better
(one-line) method for accomplishing this?

Thanks,
Tom
This is not really 'one-line' since you have to import two modules
first, but it looks nicer...:

import sys, os
print sys.argv[0] # absolute file name
print os.path.dirname(sys.argv[0]) # absolute dir name

Nov 3 '07 #4
En Sat, 03 Nov 2007 10:07:10 -0300, Giampaolo Rodola' <gn****@gmail.com>
escribió:
On 3 Nov, 04:21, klenwell <klenw...@gmail.comwrote:
>In PHP you have the __FILE__ constant which gives you the value of the
absolute path of the file you're in (as opposed to the main script
file.)
This is not really 'one-line' since you have to import two modules
first, but it looks nicer...:

import sys, os
print sys.argv[0] # absolute file name
print os.path.dirname(sys.argv[0]) # absolute dir name
Note that this returns the location of the *main* script, not the current
module, as the OP explicitely asked for.

--
Gabriel Genellina

Nov 3 '07 #5
I'm using Mac OS X, and it get:

Python 2.5 (r25:51918, Sep 19 2006, 08:49:13)
[GCC 4.0.1 (Apple Computer, Inc. build 5341)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>import os
os.getcwd()
'/Users/jeff'
>>os.path.realpath(os.path.pardir)
'/Users'
>>>
The __file__ construct is fine from within a module and is probably
more inline with what the OP was looking for anyways.

On Nov 3, 2007, at 7:18 AM, Bjoern Schliessmann wrote:
Jeff McNeil wrote:
>I've used the 'os.path.realpath(os.path.pardir)' construct in a
couple of scripts myself.

In Windows? Using Linux, this gives me "..".

I use os.path.dirname(os.path.abspath(__file__))
>That ought to work within the interactive interpreter.

Why do you also enter that code in the interpreter? If it is in a
module, you should always be able to use __file__.

Regards,
Björn

--
BOFH excuse #238:

You did wha... oh _dear_....

--
http://mail.python.org/mailman/listinfo/python-list
Nov 3 '07 #6
On Nov 3, 4:18 am, Bjoern Schliessmann <usenet-
mail-0306.20.chr0n...@spamgourmet.comwrote:
Jeff McNeil wrote:
I've used the 'os.path.realpath(os.path.pardir)' construct in a
couple of scripts myself.

In Windows? Using Linux, this gives me "..".

I use os.path.dirname(os.path.abspath(__file__))
That ought to work within the interactive interpreter.

Why do you also enter that code in the interpreter? If it is in a
module, you should always be able to use __file__.

Regards,

Björn

--
BOFH excuse #238:

You did wha... oh _dear_....
I use os.path.dirname(os.path.abspath(__file__))
That makes sense, as it is almost a literal translation of what I'm
used to using in PHP. Thanks for pointing this out.

Nov 3 '07 #7
klenwell wrote:
Bjoern Schliessmann wrote:
>I use os.path.dirname(os.path.abspath(__file__))

That makes sense, as it is almost a literal translation of what
I'm used to using in PHP. Thanks for pointing this out.
You're welcome, happy coding :)

Regards,
Björn

--
BOFH excuse #286:

Telecommunications is downgrading.

Nov 4 '07 #8
On 3 Nov, 15:46, "Gabriel Genellina" <gagsl-...@yahoo.com.arwrote:
En Sat, 03 Nov 2007 10:07:10 -0300, Giampaolo Rodola' <gne...@gmail.com
escribió:
On 3 Nov, 04:21, klenwell <klenw...@gmail.comwrote:
In PHP you have the __FILE__ constant which gives you the value of the
absolute path of the file you're in (as opposed to the main script
file.)
This is not really 'one-line' since you have to import two modules
first, but it looks nicer...:
import sys, os
print sys.argv[0] # absolute file name
print os.path.dirname(sys.argv[0]) # absolute dir name

Note that this returns the location of the *main* script, not the current
module, as the OP explicitely asked for.

--
Gabriel Genellina
Whoops! You're right.

Nov 5 '07 #9
interestingly...
I wanted to reuse this code so i wrote function in a file

def getParentDir():
import os
return os.path.dirname(os.path.abspath(__file__))
and called this function, in another file, its giving me parent
directory of file where this function is defined.?
how to reuse this piece of code then? or am i doing something wrong?

btw using __path__[0], I can get the parent directory of file too...
sandip


On Nov 5, 5:09 am, Giampaolo Rodola' <gne...@gmail.comwrote:
On 3 Nov, 15:46, "Gabriel Genellina" <gagsl-...@yahoo.com.arwrote:
En Sat, 03 Nov 2007 10:07:10 -0300, Giampaolo Rodola' <gne...@gmail.com
escribió:
On 3 Nov, 04:21, klenwell <klenw...@gmail.comwrote:
>In PHP you have the __FILE__ constant which gives you the value of the
>absolute path of the file you're in (as opposed to the main script
>file.)
This is not really 'one-line' since you have to import two modules
first, but it looks nicer...:
import sys, os
print sys.argv[0] # absolute file name
print os.path.dirname(sys.argv[0]) # absolute dir name
Note that this returns the location of the *main* script, not the current
module, as the OP explicitely asked for.
--
Gabriel Genellina

Whoops! You're right.

Nov 5 '07 #10
On Nov 5, 1:07 am, sandipm <sandip.m...@gmail.comwrote:
interestingly...
I wanted to reuse this code so i wrote function in a file

def getParentDir():
import os
return os.path.dirname(os.path.abspath(__file__))

and called this function, in another file, its giving me parent
directory of file where this function is defined.?
This is true. __file__ is defined at the module level where the
function is defined.
how to reuse this piece of code then? or am i doing something wrong?
You have a few choices. You could implement it wherever you need it
which might actually be nice from a OO point of view. You could modify
the function above to accept a parameter and operate on the __file__
attribute of that parameter. Or, you could use the inspect module to
look at the stack and operate on the __file__ attribute of the caller.

The first one is obvious to implement, although it will only apply to
modules you have implemented. The second one I think someone has
already posted a solution to. Here is how to implement the third one
(this is also usable with a parameter).

Expand|Select|Wrap|Line Numbers
  1. import inspect
  2. import os
  3.  
  4. def getpardir(obj=None):
  5. if obj is None:
  6. obj = inspect.stack()[1][0]
  7. return os.path.dirname(inspect.getfile(obj))
  8.  
Some may choose to stay away from this sort of thing though, since
inspecting the stack can tend to feel a bit like voo-doo. Passing a
parameter is probably your best bet IMHO.

Matt

Nov 5 '07 #11

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

0
by: Chris Pomasl | last post by:
We picked up a helpdesk script from sourceforge, Mantis. This script uses the __FILE__ magic constant to ostensibly derive the path to the include directory from a script in the top level...
1
by: Chris Pomasl | last post by:
Does no one have any insight?......please? Chris -------- Original Message -------- Subject: Problem with __FILE__ magic constant Date: Tue, 06 Jan 2004 16:43:41 GMT From: Chris Pomasl...
6
by: Tom | last post by:
I'm trying to dynamically adjust the path for one of my scripts using this: $script_path = str_replace( $_SERVER, "", dirname(realpath(__FILE__)) ) . DIRECTORY_SEPARATOR; The problem: the...
1
by: Spry | last post by:
Hi, I wanted to write macros for finding the number of memory allocations and deallocations also wanted to find the locations. The code I have is a pretty big one. I have a wrapper on top of...
5
by: jake1138 | last post by:
I couldn't find an example of this anywhere so I post it in the hope that someone finds it useful. I believe this is compiler specific (I'm using gcc), as C99 defines __VA_ARGS__. Comments are...
5
by: baumann.Pan | last post by:
where are these macros defined? can I use it a release ver code?
2
by: fortepianissimo | last post by:
This is a question to all of you who use Komodo IDE for development: when I tried to debug my script which uses __file__ to get the absolute path to the file, Komodo complained that the variable is...
18
by: Lukas Ruf | last post by:
Dear all, for debugging purposes, I like the pre-compiler macros __FILE__, __FUNCTION__, __LINE__ I have been wondering if there is a short form of __FILE__ that provides only the filename...
3
by: mh | last post by:
So on most modules I import, I can access the .__file__ attribute to find the implementation. ie: >>> import time >>> time.__file__ '/data1/virtualpython/lib/python2.3/lib-dynload/timemodule.so'...
4
by: 7stud | last post by:
Hi, I'm having trouble understanding what the definition of __file__ is. With this program: ------ #data.py: def show(): print __file__
0
by: Charles Arthur | last post by:
How do i turn on java script on a villaon, callus and itel keypad mobile phone
0
by: emmanuelkatto | last post by:
Hi All, I am Emmanuel katto from Uganda. I want to ask what challenges you've faced while migrating a website to cloud. Please let me know. Thanks! Emmanuel
0
BarryA
by: BarryA | last post by:
What are the essential steps and strategies outlined in the Data Structures and Algorithms (DSA) roadmap for aspiring data scientists? How can individuals effectively utilize this roadmap to progress...
1
by: nemocccc | last post by:
hello, everyone, I want to develop a software for my android phone for daily needs, any suggestions?
1
by: Sonnysonu | last post by:
This is the data of csv file 1 2 3 1 2 3 1 2 3 1 2 3 2 3 2 3 3 the lengths should be different i have to store the data by column-wise with in the specific length. suppose the i have to...
0
by: Hystou | last post by:
There are some requirements for setting up RAID: 1. The motherboard and BIOS support RAID configuration. 2. The motherboard has 2 or more available SATA protocol SSD/HDD slots (including MSATA, M.2...
0
marktang
by: marktang | last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However,...
0
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers,...
0
tracyyun
by: tracyyun | last post by:
Dear forum friends, With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.