Subprocess.Popen() not working when reading file path from csv file

Subprocess.Popen() not working when reading file path from csv file - Printable Version

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RE: Subprocess.Popen() not working when reading file path from csv file - herwin - May-07-2021

Thanks !

Most now works using the code you mention, but not all.

the csv file has these lines:

C:\\Program Files\\BraveSoftware\\Brave-Browser\\Application\\brave.exe
C:\\Program Files\\Google\\Chrome\\Application\\chrome.exe
C:\\Program Files (x86)\\Foxit Software\\Foxit Reader\\FoxitUpdater.exe
C:\\Users\\zorin\\Documents\\Python Scripts\\test folder\\JavaUpdate.bat
C:\\Users\\zorin\\Documents\\Python Scripts\\test folder\\KeepassXC Update.bat
C:\\Program Files\\Tracker Software\\Update\\TrackerUpdate.exe
C:\\Program Files (x86)\\2BrightSparks\\SyncBackFree\\SyncBackFree.exe
C:\\Program Files\\VideoLAN\\VLC\\vlc.exe
C:\\Users\\zorin\\Documents\\Python Scripts\\test folder\\windowsupdate.bat
C:\\Users\\zorin\\AppData\\Roaming\\Zoom\\bin\\Zoom.exe

The code works fine for all lines, except 2:

SyncbackFree (7)
vlc.exe (8)

if I chose either of these from my menu I get this error message:

Error:Traceback (most recent call last):
  File "test_csv.py", line 33, in <module>
    mainmenu()
  File "test_csv.py", line 31, in mainmenu
    subprocess.Popen([prg])
  File "C:\Users\zorin\AppData\Local\Programs\Python\Python38\lib\subprocess.py", line 858, in __init__
    self._execute_child(args, executable, preexec_fn, close_fds,
  File "C:\Users\zorin\AppData\Local\Programs\Python\Python38\lib\subprocess.py", line 1311, in _execute_child
    hp, ht, pid, tid = _winapi.CreateProcess(executable, args,
FileNotFoundError: [WinError 2] The system cannot find the file specified

I copied the line from the csv into a command prompt and the programs open fine, so I know the paths and file names are correct.

Any suggestions why these two give an error message and it works for the rest?

RE: Subprocess.Popen() not working when reading file path from csv file - Gribouillis - May-07-2021

Ask Python to print(repr(prg)) before it attempts to execute each program with subprocess.Popen()

RE: Subprocess.Popen() not working when reading file path from csv file - ibreeden - May-07-2021

I still believe something is going wrong with the interpretation of special characters. For example: you can insert a "vertical tab" by asigning the literal: "\v".
See this:

>>> print("C:\\Program Files\\VideoLAN\\VLC\\vlc.exe")
C:\Program Files\VideoLAN\VLC\vlc.exe
>>> print("C:\Program Files\VideoLAN\VLC\vlc.exe")
C:\Program Files\VideoLAN\VLC
                             lc.exe

>>> print("C:\\Program Files (x86)\\2BrightSparks\\SyncBackFree\\SyncBackFree.exe")
C:\Program Files (x86)\2BrightSparks\SyncBackFree\SyncBackFree.exe
>>> print("C:\Program Files (x86)\2BrightSparks\SyncBackFree\SyncBackFree.exe")
C:\Program Files (x86)BrightSparks\SyncBackFree\SyncBackFree.exe

In the first example ("C:\Program Files\VideoLAN\VLC\vlc.exe") you see the "\v" is replaced by a "vertical tab".
In the second example ("C:\Program Files (x86)\2BrightSparks\SyncBackFree\SyncBackFree.exe") you can see the "\2" is replaced by ... I don't know. It disappeared. Apparently it is seen as an octal code.

See String literals to see how backslashes are handled.
Could it be something like this is happening when assigning literals to strings?

I believe it is allowed in Python for Windows to use the forward slash instead of the backslash in folder paths. Perhaps you can try that.

RE: Subprocess.Popen() not working when reading file path from csv file - herwin - May-07-2021

Thanks for all your help.

When printing the path before the subprocess.popen I noticed that in the file paths for the two programs where it did not work the space between 'Program' and 'Files' was replaced with '\xa0'

When I manually retyped the files paths in the csv file that was fixed and now it works fine.

Thanks again