I'm trying to open a windows media file on my desktop although it doesn't seem to open anything at all, what is the issue please?
elif action == "Tutorial":
os.system("C:\\Program Files (x86)\Windows Media Player\wmplayer.exe" "C:\\Users\Angus\Desktop\Test.mkv"
there are so many things wrong here,
you did not provide a MCVE.
You don't show any evidence of checking that the elif branch ever
executed in the first place.
You are missing a close ) on os.system(.
You use os.system instead of something in subprocess so you get no error information except the return code which you do not do anything with.
you do not specify a command for os.system like start, just a file which is not valid in bash, just try it in a cmd prompt.
You did not escape the file path so every space makes the program treat it as a seperate argument, you need to add '' quotes around the file name for it to be a valid single path.
You are clearly on windows but not making use of the os.startfile function to do exactly what you are trying to do.
Related
Working with Pure Data, trying to record audio output from a patch I've made, and am 1) unable to create a file within pure data to write to and 2) attempting to use the writesf~ object causes the program to freeze after about two to three seconds. I suspect the two things are related- perhaps the program is attempting to write data somewhere, somehow, but it's going in the wrong place or some such and causing the program to freeze?
I've uninstalled the latest Pure Data release (0.51-1) and installed an earlier stable release (0.5-2) and even tried an alternative called "purr data (latest release)" all with the exact same result on my windows 10 acer laptop: no file created, and program freezes after a few seconds.
I'm testing with this patch:
I first click on the message that reads "open rec.wav" then the start then the stop, and if I take longer than three or so seconds to click on "stop" the program freezes, otherwise nothing at all happens.
I have performed system wide search for the audio file, including the folder that the patch is in, all to no avail.
Any trouble shooting hints will be carefully attempted.
Are you sure you have write-permissions on the target directory?
If your example you use rec.wav which has no explicit target directory (and is just using the "current", so it's hard to tell from outside what this directory would be).
#max-n's answer suggests to use /tmp/foo.wav which is an illegal directory on Windows. Due to a known bug, using an illegal (or otherwise non-writable) path will lock up Pd.
If your "current" directory happens to be your system root (aka C:\), you might well lack the permissions to write there.
You could check by starting the Pd from the cmdline and see whether the terminal spits out any weird errors:
⊞ Win+R
type cmd and hit Enter
in the opening terminal type the full path to your Pd-executable, e.g.:
C:\Program Files\Pd\bin\pd + Enter
(ideally leave out the extension (that is: use .../pd rather than .../pd.exe)
If the problem is indeed a permission problem, you can simply work around it by specifying the full path of the output file (and make sure that it is in a writable directory).
The easiest way to do this is by using a file-selector to choose the output file:
[bang(
|
[savepanel]
|
[open $1(
|
[writesf~]
There might be a reason why the helpfile uses a [delay 1000] to schedule a stop message in a predefined time.
When running an interactive session, PyCharm thinks of os.getcwd() as my project's directory. However, when I run my script from the command line, PyCharm thinks of os.getcwd() as the directory of the script.
Is there a good workaround for this? Here is what I tried and did not like:
going to Run/Edit Configurations and changing the working directory manually. I did not like this solution, because I will have to do it for every script that I run.
having one line in my code that "fixes" the path for the purposes of interactive sessions and commenting it out before running from command line. This works, but feels wrong.
Is there a way to do this or is it just the way it is supposed to be? Maybe I shouldn't be trying to run random scripts within my project?
Any insight would be greatly appreciated.
Clarification:
By "interactive session" I mean being able to run each line individually in a Python/IPython Console
By "running from command line" I mean creating a script my_script.py and running python path_to_myscript/my_script.py (I actually press the Run button at PyCharm, but I think it's the same).
Other facts that might prove worth mentioning:
I have created a PyCharm project. This contains (among other things) the package Graphs, which contains the module Graph and some .txt files. When I do something within my Graph module (e.g. read a graph from a file), I like to test that things worked as expected. I do this by running a selection of lines (interactively). To read a .txt file, I have to go (using os.path.join()) from the current working directory (the project directory, ...\\project_name) to the module's directory ...\\project_name\\Graphs, where the file is located. However, when I run the whole script via the command line, the command reading the .txt file raises an Error, complaining that no file was found. By looking on the name of the file that was not found, I see that the full file name is something like this:
...\\project_name\\Graphs\\Graphs\\graph1.txt
It seems that this time the current working directory is ...\\project_name\\Graphs\\, and my os.path.join() command actually spoils it.
I user various methods in my python scripts.
set the working directory as first step of your code using os.chdir(some_existing_path)
This would mean all your other paths should be referenced to this, as you hard set the path. You just need to make sure it works from any location and your specifically in your IDE. Obviously, another os.chdir() would change the working directory and os.getcwd() would return the new working directory
set the working directory to __file__ by using os.chdir(os.path.dirname(__file__))
This is actually what I use most, as it is quite reliable, and then I reference all further paths or file operations to this. Or you can simply refer to as os.path.dirname(__file__) in your code without actually changing the working directory
get the working directory using os.getcwd()
And reference all path and file operations to this, knowing it will change based on how the script is launched. Note: do NOT assume that this returns the location of your script, it returns the working directory of the shell !!
[EDIT based on new information]
By "interactive session" I mean being able to run each line
individually in a Python/IPython Console
By running interactively line-by-line in a Python console, the __file__ is not defined, afterall: you are not executing a file. Hence you cannot use os.path.dirname(__file__) you will have to use something like os.chdir(some_known_existing_dir) to reference a path. As a programmer you need to be very aware of working directory and changes to this, your code should reflect that.
By "running from command line" I mean creating a script my_script.py
and running python path_to_myscript/my_script.py (I actually press the
Run button at PyCharm, but I think it's the same).
This, both executing a .py from command line as well as running in your IDE, will populate the __file__, hence you can use os.path.dirname(__file__)
HTH
I am purposely adding another answer to this post, in regards the following:
Other facts that might prove worth mentioning:
I have created a PyCharm project. This contains (among other things)
the package Graphs, which contains the module Graph and some .txt
files. When I do something within my Graph module (e.g. read a graph
from a file), I like to test that things worked as expected. I do this
by running a selection of lines (interactively). To read a .txt file,
I have to go (using os.path.join()) from the current working directory
(the project directory, ...\project_name) to the module's directory
...\project_name\Graphs, where the file is located. However, when I
run the whole script via the command line, the command reading the
.txt file raises an Error, complaining that no file was found. By
looking on the name of the file that was not found, I see that the
full file name is something like this:
...\project_name\Graphs\Graphs\graph1.txt It seems that this time
the current working directory is ...\project_name\Graphs\, and my
os.path.join() command actually spoils it.
I strongly believe that if a python script takes input from any file, that the author of the script needs to cater for this in the script.
What I mean is you as the author need to make sure you know the following regardless of how your script is executed:
What is the working directory
What is the script directory
These two you have no control over when you hand off your script to others, or run it on other peoples machines. The working directory is dependent on how the script is launched. It seems that you run on Windows, so here is an example:
C:\> c:\python\python your_script.py
The working directory is now C:\ if your_script.py is in C:\
C:\some_dir\another_dir\> c:\python\python.exe c:\your_script_dir\your_script.py
The working directory is now C:\some_dir\another_dir
And the above example may even give different results if the SYSTEM PATH variable is set to the path of the location of your_script.py
You need to ensure that your script works even if the user(s) of your script are placing this in various locations on their machines. Some people (and I don't know why) tend to put everything on the Desktop. You need to ensure your script can cope with this, including any spaces in the path name.
Furthermore, if your script is taking input from a file, the you as the author need to ensure that you can cope with changes in working directory, and changes of script directory. There are a few things you may consider:
Have your script input from a known (static) directory, something like C:\python_input\
Have your script input from a known (configurable) directory, use ConfigParser, you can search here on stackoverflow on many posts
Have your script input from a known directory related to the location of the script (using os.path.dirname(__file__))
any other method you may employ to ensure your script can get to the input
Ultimately this is all in your control, and you need to code to ensure it is working.
HTH,
Edwin.
I am writing a program that handles some data on a server. Throughout the program, many files are made and sent as input into other programs. To do this, I usually make the command string, then run it like so:
cmd = "prog input_file1 input_file2 > outputfile"
os.system(cmd)
When I run the command, however, the programs being called report that they cannot open the files. If I run the python code on my local computer, it is fine. When I loaded it onto the server, it started to fail. I think this is related to issues with permissions, but am not sure how I can fix this. Many of the files, particularly the output files, are being created at run time. The input files have full permissions for all users. Any help or advice would be appreciated!
Cheers!
The python code you list is simple and correct, so the problem is likely not in the two lines of your example. Here are some related areas for you to check out.
Permissions
The user running the python script must have the appropriate permission (read, write, execute). I see from comments that you've already checked this.
What command are you running
If the command is literally typed into your source code like in the example, then you know what command is being run, but if you are generating any part of it (eg. the list of operands, the name of the output file, other parameters, etc), make sure there are no bugs in the portions of your code that generate the command. For example before the call to os.system(cmd) consider including a line like print("About to execute: " + cmd) so you can see exactly what will be run.
Directly invoke the command
If all the above looks good, try to execute the command directly at a terminal on your server. What output do you get then. It's possible that the problem is with the underlying command itself rather than your python code.
Consider I have the following :
An Excel workbook, which generates a .txt file (through a macro).
An executable file (.exe) which can parse this .txt file.
My objective here is to program the following algorithm :
Get the user to enter his data in the worksheets.
Prepare the .txt file according to what the user entered.
Pass the newly created .txt file to the external program (.exe).
Now, the first two steps work perfectly, I can generate the proper .txt file. The problem comes when I need to pass it to the external executable. Here's what's tried and observed :
Calling Shell() with : "C:\path\to\program.exe" "C:\path\to\file.txt" (EDIT : as a single string) ; simple enough, yet this does not work : the external .exe doesn't like being given a path. I have also tried entering the command directly into Windows' Execute utility : same. It seems like giving the program a path to the .txt isn't enough.
Dragging the .txt file onto the program's .exe works! The external executable does its work correctly. Here, it is as if I had passed the "file" to the program, not just its path. As a UNIX user, this sound like quite a non-sense to me (without a notion of stream or pipe), so maybe I'm missing something here...
Now, here's my question. When dragging-n-dropping a file onto an executable, how does Windows "translate" it ? Obviously, it does not translate it to "pass the file's path as the program's first parameter". How can I pass the .txt file to the executable program, without just passing its path like I did with my first Shell() call ?
A few other notes :
I am using Microsoft Office Excel 2010 on Windows 7. I'm already dying from it, thanks for your concern.
This external .exe I'm talking about cannot be modified and recompiled (which would be awesome), that's the tricky thing. I have to use it as it is, whatever happens.
Using Shell() is not a problem, if you give me the proper command/fix. I have also tried calling Run on a VBA.CreateObject("WScript.Shell"), same result.
Now, here's my question. When dragging-n-dropping a file onto an
executable, how does Windows "translate" it ? Obviously, it does not
translate it to "pass the file's path as the program's first
parameter".
It does exactly that. Create a batch file:
#echo off
echo You passed parameter: %1
pause
Save it as test.bat
Browse to it in file explorer, and drag/drop something onto it:
Previous comments:
Looks like you have to send the path and filename as one parameter, e.g.:
Shell("C:\path\to\program.exe C:\path\to\file.txt")
or if the paths have spaces in them, maybe:
Shell("""C:\path\to\program.exe"" ""C:\path\to\file.txt""")
http://social.msdn.microsoft.com/Forums/en-US/a3a3d1a7-5c9a-4c91-ab96-41d367eac2fb/using-shell-function-in-vba-how-do-i-pass-a-parameter?forum=accessdev
I am developing a Qt application in Linux. I wanted to pass Linux commands to a terminal. That worked but now i also want to get a response from the terminal for this specific command.
For example,
ls -a
As you know this command lists the directories and files of the current working directory. I now want to pass the returned values from the ls call to my application. What is a correct way to do this?
QProcess is the qt class that will let you spawn a process and read the result. There's an example of usage for reading the result of a command on that page.
popen() ， api of linux systerm , return FILE * that you can read it like a file descriptor， may help youp erhaps。
Parsing ls(1) output is dangerous -- make a few files with funny names in a directory and test it out:
touch "one file"
touch "`printf "\x0a\x0a\x0ahello\x0a world"`"
That creates two files in the current working directory. I expect your attempts to parse ls(1) output won't work. This might be alright if you're showing the results to a human, (though a human will be immensely confused if a filename includes output that looks just like ls(1) output!) but if you're trying to present something like an explorer.exe or Finder.app representation of files in the filesystem, this is horribly broken.
Instead, use opendir(3), readdir(3), and closedir(3) to read directory entries yourself. This will be safer, more portable, and (as a side benefit) slightly better performing.