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How do you define a local path in python

Good morning, I can indicate how to enter a path of internal hard disk in python, currently use the statement:
file = GETfile() or 'http://**********'
I would like to put a path to a local file, but it does not work, where am I wrong?
file = GETfile() or 'D:\xxx\xxxx\playlist\playlist.m3u'

\ is a escape character. You have three options.
1) use /. This, as a bonus works for linux as well:
'D:/xxx/xxxx/playlist/playlist.m3u'
2) escape the backslash
'D:\\xxx\\xxxx\\playlist\\playlist.m3u'
3) use raw strings:
r'D:\xxx\xxxx\playlist\playlist.m3u'

A correct answer is already given, but some additional information when working with local drive paths on Windows operating system.
Personally I would go with the r'D:\dir\subdir\filename.ext' format, however the other two methods already mentioned are valid as well.
Furthermore, file operations on Windows are limited by Explorer to a 256 character limit. Longer path names will usually result in an OS error.
However there is a workaround, by pre fixing "\\?\" to a long path.
Example of a path which does not work:
D:\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\filename.ext
Same file path which does work:
\\?\D:\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\reallyreallyreallyreallyreallylonglonglonglongdir\filename.ext
so the following code I use to change filenames to include the "\\?\":
import os
import platform
def full_path_windows(filepath):
if platform.system() == 'Windows':
if filepath[1:3] == ':\\':
return u'\\\\?\\' + os.path.normcase(filepath)
return os.path.normcase(filepath)
I use this for every path to file (or directories), it will return the path with a prefix. The path does not need to exist; so you can use this also before you create a file or directory, to ensure you are not running into the Windows Explorer limitations.
HTH

Find desktop folder in a custom location? [duplicate]

I have this small program and it needs to create a small .txt file in their 'My Documents' Folder. Here's the code I have for that:
textfile=open('C:\Users\MYNAME\Documents','w')
lines=['stuff goes here']
textfile.writelines(lines)
textfile.close()
The problem is that if other people use it, how do I change the MYNAME to their account name?

Use os.path.expanduser(path), see http://docs.python.org/library/os.path.html
e.g. expanduser('~/filename')
This works on both Unix and Windows, according to the docs.
Edit: forward slash due to Sven's comment.

This works without any extra libs:
import ctypes.wintypes
CSIDL_PERSONAL = 5 # My Documents
SHGFP_TYPE_CURRENT = 0 # Get current, not default value
buf= ctypes.create_unicode_buffer(ctypes.wintypes.MAX_PATH)
ctypes.windll.shell32.SHGetFolderPathW(None, CSIDL_PERSONAL, None, SHGFP_TYPE_CURRENT, buf)
print(buf.value)
Also works if documents location and/or default save location is changed by user.

On Windows, you can use something similar what is shown in the accepted answer to the question: Python, get windows special folders for currently logged-in user.
For the My Documents folder path, useshellcon.CSIDL_PERSONALin the shell.SHGetFolderPath() function call instead of shellcon.CSIDL_MYPICTURES.
So, assuming you have the PyWin32 extensions1 installed, this might work (see caveat in Update section below):
>>> from win32com.shell import shell, shellcon
>>> shell.SHGetFolderPath(0, shellcon.CSIDL_PERSONAL, None, 0)
u'<path\\to\\folder>'
Update: I just read something that said that CSIDL_PERSONAL won't return the correct folder if the user has changed the default save folder in the Win7 Documents library. This is referring to what you can do in library's Properties dialog:
The checkmark means that the path is set as the default save location.
I currently am unware of a way to call the SHLoadLibraryFromKnownFolder() function through PyWin32 (there currently isn't a shell.SHLoadLibraryFromKnownFolder. However it should be possible to do so using the ctypes module.
1Installers for the latest versions of the Python for Windows Extensions are currently available from: http://sourceforge.net/projects/pywin32

How to write OS X Finder Comments from python?

I'm working on a python script that creates numerous images files based on a variety of inputs in OS X Yosemite. I am trying to write the inputs used to create each file as 'Finder comments' as each file is created so that IF the the output is visually interesting I can look at the specific input values that generated the file. I've verified that this can be done easily with apple script.
tell application "Finder" to set comment of (POSIX file "/Users/mgarito/Desktop/Random_Pixel_Color/2015-01-03_14.04.21.png" as alias) to {Val1, Val2, Val3} as Unicode text
Afterward, upon selecting the file and showing its info (cmd+i) the Finder comments clearly display the expected text 'Val1, Val2, Val2'.
This is further confirmed by running mdls [File/Path/Name] before and after the applescript is used which clearly shows the expected text has been properly added.
The problem is I can't figure out how to incorporate this into my python script to save myself.
Im under the impression the solution should* be something to the effect of:
VarList = [Var1, Var2, Var3]
Fiele = [File/Path/Name]
file.os.system.add(kMDItemFinderComment, VarList)
As a side note I've also look at xattr -w [Attribute_Name] [Attribute_Value] [File/Path/Name] but found that though this will store the attribute, it is not stored in the desired location. Instead it ends up in an affiliated pList which is not what I'm after.

Here is my way to do that.
First you need to install applescript package using pip install applescript command.
Here is a function to add comments to a file:
def set_comment(file_path, comment_text):
import applescript
applescript.tell.app("Finder", f'set comment of (POSIX file "{file_path}" as alias) to "{comment_text}" as Unicode text')
and then I'm just using it like this:
set_comment('/Users/UserAccountName/Pictures/IMG_6860.MOV', 'my comment')

After more digging, I was able to locate a python applescript bundle: https://pypi.python.org/pypi/py-applescript
This got me to a workable answer, though I'd still prefer to do this natively in python if anyone has a better option?
import applescript
NewFile = '[File/Path/Name]' <br>
Comment = "Almost there.."
AddComment = applescript.AppleScript('''
on run {arg1, arg2}
tell application "Finder" to set comment of (POSIX file arg1 as alias) to arg2 as Unicode text
return
end run
''')
print(AddComment.run(NewFile, Comment))
print("Done")

This is the function to get comment of a file.
def get_comment(file_path):
import applescript
return applescript.tell.app("Finder", f'get comment of (POSIX file "{file_path}" as alias)').out
print(get_comment('Your Path'))

Another approach is to use appscript, a high-level Apple event bridge that is sadly no longer officially supported but still works (and saw an updated release in Jan. 2021). Here is an example of reading and setting the comment on a file:
import appscript
import mactypes
# Get a handle on the Finder.
finder = appscript.app('Finder')
# Tell Finder to select the file.
file = finder.items[mactypes.Alias("/path/to/a/file")]
# Print the current comment
comment = file.comment()
print("Current comment: " + comment)
# Set a new comment.
file.comment.set("New comment")
# Print the current comment again to verify.
comment = file.comment()
print("Current comment: " + comment)
Despite that the author of appscript recommends against using it in new projects, I used it recently to create a command-line utility called Urial for the specialized purpose of writing and updating URIs in Finder comments. Perhaps its code can serve as an an additional example of using appscript to manipulate Finder comments.

Read registry value with python problems

I feel like I am taking crazy pills. So for security on an api at work I am using, I have to read 2 things from the registry, that I then pass to suds. The problem is with reading the registry values. No matter what I do, I get "Error2 the system cannot find the file specified". I know that the registry file is there, yet it won't let me read it. I have tried the code below on 2 different 2008 r2 servers. On one windows 7 box, I am able to read the values...but only on one machine. Below is the code, with the actual directory I need changed(to protect anonymity)
from _winreg import *
key = OpenKey(HKEY_LOCAL_MACHINE, r"Software\a\b", 0, KEY_ALL_ACCESS)
devguid = QueryValueEx(key, "DeviceID")
devid = QueryValueEx(key, "DeviceGUID")
devnm = socket.gethostname()
If I change the directory to something other than \a\b, it works fine. I have verified that the permissions on these directories are the exact same as directories I can read from.
Also, I can run the following command from cmd and get the output I need:
reg query HKLM\software\a\b /v DeviceGUID
But when I run it from a python script, it says cannot find file specified.
import os
cmd = "reg query HKEY_LOCAL_MACHINE\software\a\b /v DeviceGUID"
a = os.system(cmd)
print a
Running my script as admin or anything doesn't help. For some reason, python is unable to try and ready registry....

First of all you do need to make sure that your backslashes are suitably escaped, or use raw strings as per the first code sample. I'm going to assume that you've done that.
The most likely explanation is that you use 32 bit Python on a 64 bit system. And so are subject to the registry redirector serving up the 32 bit view of the registry.
Either use 64 bit Python, or specifically open they key with a 64 bit view. Do the latter by specifying the KEY_WOW64_64KEY flag.

tarfile and user,group information problem

I am using python tarfile module to extract files from a *.tgz file. Here what I use:
import tarfile
tar = tarfile.open("some.tar")
tar.extractall(".")
tar.close()
Assume "some.tar" contents as:
-a.txt ===> user:usr1 , group: grp1
-b.txt ===> user:usr2 , group: grp2
But after extracting I lose all of user,group,date... information. They now belong to whoever calls the script(in my case root). They become like:
-a.txt ===> user:root , group: root
-b.txt ===> user:root , group: root
Is there a way to keep file owner,date information of files?
From tarfile module page:
-handles directories, regular files, hardlinks, symbolic links, fifos, character devices and block devices and is able to acquire and restore file information like timestamp, access permissions and owner.
From this statement I understand that is is very well possible to do this by "tarfile" module, or do I understand it wrong?
Python version is 2.6.1
Edit: I am running this script as root
Thanks

As guettli says, you have to be root to be able to change the ownership of a file to somebody else. Otherwise, you open a huge security hole. This is true when using the tar(1) program or when trying to use the tarfile package from python.
Note, though, that some earlier version of Python have a bug (see issue in comments below) that means files extracted by root are owned by root instead of the real owner (user and group).

First, your script needs to run as root (on unix like systems). Otherwise, you can't use chown.
You need to get the TarInfo object for the files:
http://docs.python.org/library/tarfile.html#tarfile.TarInfo
There you get uid (user id) and gid (group id) and (or user name).
Then you need to use chown.