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From: Thomas Jollans on 7 Aug 2010 07:46
On 08/07/2010 01:10 PM, Shambhu Sharma wrote:
> Hi,
>
> I am new to Python. I was trying to use os.unlink function in
> windows. But i am getting error:
> OSError: [Errno 2] No such file or directory:
> 'C:\\SHAMBHU\\tmp\\text_delete.txt'
>
> Input file to os.unlink is: 'C:\SHAMBHU\tmp\text_delete.txt'. But
> os.unlink is adding extra backslash with pathname.

No, it isn't. What you're seeing is simply the repr() of the path name
string.

>>> p = r'C:\SHAMBHU\tmp\text_delete.txt'
>>> p
'C:\\SHAMBHU\\tmp\\text_delete.txt'
>>> print(p)
C:\SHAMBHU\tmp\text_delete.txt
>>>


I think the file you're trying to delete probably doesn't exist. Why
don't you double-check that.



> I tried with
> Python2.5 and Python3.1 but got same error.
> Please suggest how to remove this error.
>
> --
> If linux doesn't have a solution, then u have a wrong problem.
>
> Shambhu Kumar Sharma
> 91-98864 91913
>

From: Shambhu on 8 Aug 2010 07:41
Hi Thomas,

I checked, file is present. Here is my sample script:
import os
filename = "C:\SHAMBHU\tmp\text_delete.txt"
os.unlink(filename)

File "C:\SHAMBHU\tmp\text_delete.txt" is accessible but "C:\\SHAMBHU\
\tmp\\text_delete.txt" is not (with extra backslash in path which is
added by os.unlink).

Regards.
Shambhu.



On Aug 7, 4:46 pm, Thomas Jollans <tho...(a)jollans.com> wrote:
> On 08/07/2010 01:10 PM, Shambhu Sharma wrote:
>
> > Hi,
>
> >         I am new to Python. I was trying to use os.unlink function in
> > windows. But i am getting error:
> > OSError: [Errno 2] No such file or directory:
> > 'C:\\SHAMBHU\\tmp\\text_delete.txt'
>
> > Input file to os.unlink is: 'C:\SHAMBHU\tmp\text_delete.txt'. But
> > os.unlink is adding extra backslash with pathname.
>
> No, it isn't. What you're seeing is simply the repr() of the path name
> string.
>
> >>> p = r'C:\SHAMBHU\tmp\text_delete.txt'
> >>> p
>
> 'C:\\SHAMBHU\\tmp\\text_delete.txt'>>> print(p)
>
> C:\SHAMBHU\tmp\text_delete.txt
>
>
>

> I think the file you're trying to delete probably doesn't exist. Why
> don't you double-check that.
>
> > I tried with
> > Python2.5 and Python3.1 but got same error.
> > Please suggest how to remove this error.
>
> > --
> > If linux doesn't have a solution, then u have a wrong problem.
>
> > Shambhu Kumar Sharma
> > 91-98864 91913
>
>

From: Thomas Jollans on 8 Aug 2010 08:17
On 08/08/2010 01:41 PM, Shambhu wrote:
> Hi Thomas,
>
> I checked, file is present. Here is my sample script:
> import os
> filename = "C:\SHAMBHU\tmp\text_delete.txt"
> os.unlink(filename)
>
> File "C:\SHAMBHU\tmp\text_delete.txt" is accessible but "C:\\SHAMBHU\
> \tmp\\text_delete.txt" is not (with extra backslash in path which is
> added by os.unlink).

os.unlink isn't adding anything. The extra backslashes you're seeing are
being added when DISPLAYING the file name string. That's because Python
uses backslashes to escape special characters in strings.

>>> print("C:\\SHAMBHU\\tmp\\text_delete.txt")
C:\SHAMBHU\tmp\text_delete.txt
>>> print("C:\SHAMBHU\tmp\text_delete.txt")
C:\SHAMBHU mp ext_delete.txt
>>>

'\t' is the TAB character.

What is the error message, exactly, when you run the above script? Since
you didn't escape the backslashes properly, I expect it refers to
'C:\\SHAMBHU\tmp\text_delet.txt' -- The first backslash is still a
backslash -- it gets doubled when printed as a string (but NOT when
passed to the OS by unlink), but the second and third ones were used to
create TAB characters. Probably.

Either always double backslashes in paths, or use raw string literals
(r"C:\SHAMBHU\tmp\text_delete.txt" -- keeps the \s) (or use forward
slashes in paths...)

>
> Regards.
> Shambhu.
>
>
>
> On Aug 7, 4:46 pm, Thomas Jollans <tho...(a)jollans.com> wrote:
>> On 08/07/2010 01:10 PM, Shambhu Sharma wrote:
>>
>>> Hi,
>>
>>> I am new to Python. I was trying to use os.unlink function in
>>> windows. But i am getting error:
>>> OSError: [Errno 2] No such file or directory:
>>> 'C:\\SHAMBHU\\tmp\\text_delete.txt'
>>
>>> Input file to os.unlink is: 'C:\SHAMBHU\tmp\text_delete.txt'. But
>>> os.unlink is adding extra backslash with pathname.
>>
>> No, it isn't. What you're seeing is simply the repr() of the path name
>> string.
>>
>>>>> p = r'C:\SHAMBHU\tmp\text_delete.txt'
>>>>> p
>>
>> 'C:\\SHAMBHU\\tmp\\text_delete.txt'>>> print(p)
>>
>> C:\SHAMBHU\tmp\text_delete.txt
>>
>>
>>
>
>> I think the file you're trying to delete probably doesn't exist. Why
>> don't you double-check that.
>>
>>> I tried with
>>> Python2.5 and Python3.1 but got same error.
>>> Please suggest how to remove this error.
>>
>>> --
>>> If linux doesn't have a solution, then u have a wrong problem.
>>
>>> Shambhu Kumar Sharma
>>> 91-98864 91913
>>
>>
>

From: Steven D'Aprano on 8 Aug 2010 09:29
On Sun, 08 Aug 2010 04:41:14 -0700, Shambhu wrote:

> Hi Thomas,
>
> I checked, file is present. Here is my sample script:
> import os
> filename = "C:\SHAMBHU\tmp\text_delete.txt"

Did you intend to provide a filename with two TAB characters in it?

c colon backslash s h a m b u TAB m p TAB e x t underscore d e l e t e
dot t x t

> File "C:\SHAMBHU\tmp\text_delete.txt" is accessible but "C:\\SHAMBHU\
> \tmp\\text_delete.txt" is not (with extra backslash in path which is
> added by os.unlink).

os.unlink does add any extra backslashes. You are misinterpreting what
you are seeing.



--
Steven
From: Shambhu on 9 Aug 2010 00:57
Hi Thomas, Steven,
Thanks for explanation. It is working now after
using double backslash in pathname. I was misinterpreting the display
output and thinking that it was being added by 'os' module.

Regards,
Shambhu.

T
On Aug 8, 6:29 pm, Steven D'Aprano <st...(a)REMOVE-THIS-
cybersource.com.au> wrote:
> On Sun, 08 Aug 2010 04:41:14 -0700, Shambhu wrote:
> > Hi Thomas,
>
> >            I checked, file is present. Here is my sample script:
> > import os
> > filename = "C:\SHAMBHU\tmp\text_delete.txt"
>
> Did you intend to provide a filename with two TAB characters in it?
>
> c colon backslash s h a m b u TAB m p TAB e x t underscore d e l e t e
> dot t x t
>
> > File "C:\SHAMBHU\tmp\text_delete.txt" is accessible but "C:\\SHAMBHU\
> > \tmp\\text_delete.txt" is not (with extra backslash in path which is
> > added by os.unlink).
>
> os.unlink does add any extra backslashes. You are misinterpreting what
> you are seeing.
>
> --
> Steven

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