Python, subprocess, filepath white spaces and famous 'C:/Program' is not recognized as an internal or external command

Question

Enclosing a full file path inside the "" quotes does not make it work.

cmd = "C:\Program Files (x86)\iTunes\iTunes.exe"

subprocess.popen throws an error of not being able to find an executable if there is a white space in a file-path to be executed.

A while ago I was able to find a solution which involved a use of some weird symbols or their combination... Unfortunately I can't locate a code with that example. I would appreciate if someone would point me in a right direction. Thanks in advance.

Solution 1

Backslashes in strings trigger escape characters. Since Windows fully supports the use of the forward slash as a path separator, just do that:

cmd = "C:/Program Files (x86)/iTunes/iTunes.exe"

No need to fiddle around with \\ or raw strings. ;)

Solution 2

Either use:

cmd = '"C:\\Program Files (x86)\\iTunes\\iTunes.exe"'

or

cmd = r'"C:\Program Files (x86)\iTunesr\iTunes.exe"'

Solution 3

the file path：

file_path= 'E:\\te st.py'

then you should:

file_path = '"E:\\te st.py"'

then it works, my Main.py as show blow:

import subprocess

doc = '"E:\\te st.py"'

p = subprocess.Popen ('python ' + doc , stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE)
output = p.communicate()
print output

and the te st.py is:

print 'hello world'

Comments

[Tim Pierce]

Are you sure that the problem is with the white space and not with the backslashes? Try cmd = "C:\\Program Files (x86)\\iTunes\\iTunes.exe".

[alphanumeric]

cmd = '"C:\\Program Files (x86)\\iTunes\\iTunes.exe"' won't work.

[alphanumeric]

I am not sure about r' "c:\\Program Files\\executable.exe '

[Ryan Haining]

@Sputnix 1) the first won't work or doesn't work? 2) so try it.

[Steve Barnes]

Windows doesn't support unquoted and un-escaped spaces. :(

[Max Noel]

So what, does Popen always use the shell (or whatever the equivalent is) to open external programs on Windows, even with shell=False? In that case, the fix is easy: just add quotes. cmd = '"C:/Program Files (x86)/iTunes/iTunes.exe"'

[Steve Barnes]

Without a windows machine to hand I was reluctant to suggest this without testing as it is Python for Windows that supports forward slashes in file paths rather than windows and I suspected that the nested quotes could possibly defeat this.