string to file parameter oddity

[meems]

python 2.7

f=r"C:\temp\test.txt"
print f
filein=open(f)
a=filein.read()
filein.close()
print a

it prints

Output:
C:\temp\test.txt

but then it returns ...

Error:
No such file or directory 'C:\\temp\\test.txt'

why is it adding extra \ ?
A string to file parameter oddity that I can't find explained or mentioned anywhere on the net.

help plz, thks

[nilamo]

That has nothing to do with files. Backslash (ie: \) is an escape character. If you want to actually use one in a string, you need to escape it: \\. The only reason it's working for you, is because you marked the string as raw (that's what the "r" in front of your path means). You could also use a single forward slash... python will do The Right Thing depending on what os you're on, so "c:/temp/test.txt" == "c:\\temp\\test.txt" == r"c:\temp\test.txt" == "c:/temp\\test.txt" == r"c:/temp\test.txt".
...but don't mix between the two in a single string. Other people will hate you for purposefully making things hard to read, lol.

[sparkz_alot]

Works for me.

Output:
C:\temp\test.txt
this is a test file

You could also write the line

f=r"C:\temp\test.txt"

as

f="C:/temp/test.txt"

Do you have a file named "test.txt" in "C:\temp" ?

In the future, please place code between the code (python) tags and the full traceback between the error tags.

[meems]

Yes I have a C:\temp\test.txt file

I tried swapping the backslash for a forward slash, get same error.

Also I tried changing

filein=open(f)

to

filein=open(r"C:\TEMP\test.txt")

gives same error

then tried

filein=open("C:\\TEMP\\test.txt")

gives same error

no such file or directory : ' C:\\TEMP\\test.txt"

Don't think my code is wrong, but some setting might be wrong.

[heiner55]

Then try it with a file in the same directory as your script:
f = open("test.txt")

---

Or try:
f = open("./test.txt")
f = open("c:/test.txt")
f = open("c:/temp/test.txt")

[meems]

Fixed

my file was called test.txt.txt, changed it to test.txt

windows doesn't make such errors too clear.

and the python error message with the double backslashes was a red herring. It shouldn't be doing that if it can't find a file!

thks for help.

[heiner55]

In Windows Explorer it is better to switch off the option "Hide extensions for known file types".

[nilamo]

Like I was saying, the error message never mentioned double backslashes. The python error was always telling you the file didn't exist.