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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

Python pathlib glob function fails on WindowsError: [123]?

I've written the following python function that returns a python list of File Geodatabase Paths. Please note that input_folder is a raw string and contains no unicode characters.
try:
gdbs = list(Path(input_folder).glob('**/*.gdb'))
for gdb in gdbs:
print(gdb)
except WindowsError, e:
print("error")
The problem that I'm having is that pathlib glob method is failing when it encounters unicode characters in the path of files in the directory.
I tried the following but it still fails, which I assume is because I'm not converting the paths the glob generator is coming across.
try:
gdbs = list(Path(unicode(input_folder)).glob('**/*.gdb'))
for gdb in gdbs:
print(gdb)
except WindowsError, e:
print("error")
The error message that is returned is:
WindowsError: [Error 123] The filename, directory name, or volume label syntax is incorrect: 'R:\\Data\\Africa\\Tanzania\\fromDropbox\\DART\\BRT Phase 2-3 designs\\1.12 Engineering Drawings for Service\\ROAD LIGHT\\PDF\\01.Traffic Sign(Kilwa)-??04.pdf'
Any help to handle the following error will be appreciated.

Try this :
input_folder = r'R:\Data\Africa\Tanzania\fromDropbox\DART\BRT Phase 2-3 designs\1.12 Engineering Drawings for Service\ROAD LIGHT\PDF\01.Traffic Sign(Kilwa)-??04.pdf'
The correct call should have 'r' in front of the path, and using single slash.

It seems to be a problem with pathlib because of Python 2.7 not being able to handle non-ascii characters. pathlib chokes up on international characters on Python 2 on Windows

File not found Error in reading text in python [duplicate]

This question already has answers here:
How should I write a Windows path in a Python string literal?
(5 answers)
Closed 7 months ago.
I am trying to read a text file on my hard drive via python with the following script:
fileref = open("H:\CloudandBigData\finalproj\BeautifulSoup\twitter.txt","r")
But it is giving the following error:
IOError Traceback (most recent call last)
<ipython-input-2-4f422ec273ce> in <module>()
----> 1 fileref = open("H:\CloudandBigData\finalproj\BeautifulSoup\twitter.txt","r")
IOError: [Errno 2] No such file or directory: 'H:\\CloudandBigData\x0cinalproj\\BeautifulSoup\twitter.txt'
I also tried with other way:
with open('H:\CloudandBigData\finalproj\BeautifulSoup\twitter.txt', 'r') as f:
print f.read()
Ended up with the same error. The text file is present in the directory specified.

Replace
fileref = open("H:\CloudandBigData\finalproj\BeautifulSoup\twitter.txt","r")
with
fileref = open(r"H:\CloudandBigData\finalproj\BeautifulSoup\twitter.txt","r")
Here, I have created a raw string (r""). This will cause things like "\t" to not be interpreted as a tab character.
Another way to do it without a raw string is
fileref = open("H:\\CloudandBigData\\finalproj\\BeautifulSoup\\twitter.txt","r")
This escapes the backslashes (i.e. "\\" => \).
An even better solution is to use the os module:
import os
filepath = os.path.join('H:', 'CloudandBigData', 'finalproj', 'BeautifulSoup', 'twitter.txt')
fileref = open(filepath, 'r')
This creates your path in an os-independent way so you don't have to worry about those things.
One last note... in general, I think you should use the with construct you mentioned in your question... I didn't in the answer for brevity.

I was encountering same problem. This problem resulted due to different file path notation Python.
For example, filepath in Windows reads with backward slash like: "D:\Python\Project\file.txt"
But Python reads file path with forward slash like: "D:/Python/Project/file.txt"
I used r"filepath.txt" and "os.path.join" and "os.path.abspath" to no relief. os library also generates file path in Windows notation. Then I just resorted to IDE notation.
You don't encounter this error if "file.txt" is located in same directory, as filename is appended to working directory.
PS: I am using Python 3.6 with Spyder IDE on Windows machine.

Error opening a csv file in python from a specific directory

I am very new to python and I am not having much experience in programming.
I try to open a CSV file from a specific directory and I get error.
import csv
ifile = open('F:\Study\CEN\Mini Project\Data Sets\test.csv', "rb");
Error:
Traceback (most recent call last):
File "<pyshell#6>", line 1, in <module>
ifile = open('F:\Study\CEN\Mini Project\Data Sets\test.csv', "rb");
IOError: [Errno 22] invalid mode ('rb') or filename: 'F:\\Study\\CEN\\Mini Project\\Data Sets\test.csv'
What to do ????

Use forward slashes:
ifile = open('F:/Study/CEN/Mini Project/Data Sets/test.csv', "rb");
Or at least escape your backslashes:
ifile = open('F:\\Study\\CEN\\Mini Project\\Data Sets\\test.csv', "rb");
Another option: use os.path.join:
out = os.path.abspath(os.path.join('path', 'test.csv'))

Your problem is here:
'F:\Study\CEN\Mini Project\Data Sets\test.csv'
^^
Because you did not use a raw string, Python thinks \t is supposed to mean a tab character.
You can see that in the error message, by the way: Notice how Python translated all the backslashes into double backslashes (which is how a literal backslash needs to be represented in a normal string) in all the places except the one where "backslash plus letter" actually meant something special?
Use
ifile = open(r'F:\Study\CEN\Mini Project\Data Sets\test.csv', "rb")
(and remove the semicolons, you don't need them in Python) and it should work.

Your problem is with the "\t" AND a lack of exposure to various tools in the os.path package
The correct and easiest way to deal with this problem is to use os.path.normpath, combined with the string literal r, which ensures that backslashes are not interpreted as an escape character.
(Documentation on Lexical Analysis in python can be found here: https://docs.python.org/2/reference/lexical_analysis.html)
Open interactive python by typing "python" at the command line, and do the following to see that it's dead simple.
>>> import os
>>> path = r'F:\Study\CEN\Mini Project\Data Sets\test.csv'
>>> os.path.normpath(path)
'F:\\Study\\CEN\\Mini Project\\Data Sets\\test.csv'
normpath should be used when using hardcoded paths for scripts that may have to run on both dos and unix (eg OS X). It will ensure that the right kind of slashes are used for your particular environment
On a side note, if you are working with CSV files, you should use the petl library instead of the csv module. You'll save yourself a lot of time and hassle. Install it with pip install petl

os.listdir can't see my directory

I am working on a python script that installs an 802.1x certificate on a Windows 8.1 machine. This script works fine on Windows 8 and Windows XP (haven't tried it on other machines).
I have isolated the issue. It has to do with clearing out the folder
"C:\Windows\system32\config\systemprofile\AppData\LocalLow\Microsoft\CryptURLCache\Content"
The problem is that I am using the module os and the command listdir on this folder to delete each file in it. However, listdir errors, saying the folder does not exist, when it does indeed exist.
The issue seems to be that os.listdir cannot see the LocalLow folder. If I make a two line script:
import os
os.listdir("C:\Windows\System32\config\systemprofile\AppData")
It shows the following result:
['Local', 'Roaming']
As you can see, LocalLow is missing.
I thought it might be a permissions issue, but I am having serious trouble figuring out what a next step might be. I am running the process as an administrator from the command line, and it simply doesn't see the folder.
Thanks in advance!
Edit: changing the string to r"C:\Windows\System32\config\systemprofile\AppData", "C:\Windows\System32\config\systemprofile\AppData", or C:/Windows/System32/config/systemprofile/AppData" all produce identical results
Edit: Another unusual wrinkle in this issue: If I manually create a new directory in that location I am unable to see it through os.listdir either. In addition, I cannot browse to the LocalLow or my New Folder through the "Save As.." command in Notepad++
I'm starting to think this is a bug in Windows 8.1 preview.

I encountered this issue recently.
I found it's caused by Windows file system redirector
and you can check out following python snippet
import ctypes
class disable_file_system_redirection:
_disable = ctypes.windll.kernel32.Wow64DisableWow64FsRedirection
_revert = ctypes.windll.kernel32.Wow64RevertWow64FsRedirection
def __enter__(self):
self.old_value = ctypes.c_long()
self.success = self._disable(ctypes.byref(self.old_value))
def __exit__(self, type, value, traceback):
if self.success:
self._revert(self.old_value)
#Example usage
import os
path = 'C:\\Windows\\System32\\config\\systemprofile\\AppData'
print os.listdir(path)
with disable_file_system_redirection():
print os.listdir(path)
print os.listdir(path)
ref : http://code.activestate.com/recipes/578035-disable-file-system-redirector/

You must have escape sequences in your path. You should use a raw string for file/directory paths:
# By putting the 'r' at the start, I make this string a raw string
# Raw strings do not process escape sequences
r"C:\path\to\file"
or put the slashes the other way:
"C:/path/to/file"
or escape the slashes:
# You probably won't want this method because it makes your paths huge
# I just listed it because it *does* work
"C:\\path\\to\\file"

I'm curious as to how you are able to list the contents with those two lines. You are using escape sequences \W, \S, \c, \s, \A in your code. Try escaping the back slash like this:
import os
os.listdir('C:\\Windows\\System32\\config\\systemprofile\\AppData')