Windows: tell app to open file - windows

On Windows, how do I get my app to tell another app to open a file that I just generated. For example, "WordPad, please open 'foo.rtf' that I just made." Or Word, or other big apps that may already be open with other files. I have to assume that the app may or may not be open already.
Alternatively, if I could only do the equivalent of double-clicking the file, so as to open it with its default application, that would still be all right.

Depends on how your application handles opening other files.
One would think that assuming filetype associations are configured properly in Windows, it should know what application to open .rtf files with (per your example).
In powershell, you could use gc if you're only looking at plaintext data.
http://www.ats.ucla.edu/stat/mult_pkg/faq/general/powershell_examples.htm
In Python, you would handle the file as an object, per the example here:
https://docs.python.org/2/tutorial/inputoutput.html#reading-and-writing-files
But if you wanted to launch a specific secondary application to open the file, you might try running an outside program (executable) in python?

Related

Alternative to Windows Alternate Data Streams

I have the following need to implement on Windows: file with files.
Originally I was thinking to use directory with extension. Something like "folderA.myappext", so when user clicks on it in Explorer, my app is launched instead of folder being opened. Unfortunately, I was unable to find a way to do that. Then I tried to use Alternate Data Streams. This works just fine, but several problems with it:
It works only in NTFS, so no way to send it via email or FTP as is;
Only WinRAR can properly archive it, and you still have to do extra clicks in the UI for that;
The real file size (with all streams in it) is not shown in Explorer and does not participate in showing free/used space, which can very quickly lead to big problems for the user.
No, I can't use zip or any other way to combine files into one - this is high-performance app that also requires write streaming (i.e. it changes data all the time).
Any idea how else to achieve my need on Windows? I know on MacOS you can use 'package', but there is nothing like that on Windows. Any idea?
Something like "folderA.myappext", so when user clicks on it in Explorer, my app is launched instead of folder being opened.
You can't do it based on the extension because folders don't have extensions but you can do it with desktop.ini. Windows 7 and later supports custom verbs on folders.
A working example can be found here.

Open With Application: How to detect filename in go

I have created a go application on my mac that reads/writes from files *.myext. The executable was packed into an a Bundle called "MyApp".
I can start MyApp and then read/write *.myext files, that works.
My question is: how to detect the filename if I am opening e.g. test.myext by Open With > MyApp (usually right mouse button)?
I have tried to read the file name from os.Args, but the file name is not in there.
Is there a way?
Thank you for your help!
Leo
Looks like a program started via "Open With" does not receive the name of the file it has been invoked on but rather has to obtain it using "Apple events" as described in the accepted answer here.
I am thereby afraid currently the only way to solve the problem would be to use cgo; may be along these lines.

NSWorkspace notification - application close [duplicate]

My requirement is to open a file like pdf/ppt etc and close it after 20 minutes. I am able to open the files appropriately thanks to NSWorkspace. But how can I close the files ?. NSWorkspace does not seem to have a close method.
NSWorkspace just asks the operating system to open the file, it doesn't maintain any connection to the file at all. The OS will open the file with whatever the default application is for that file type, unless you specify a particular application to use. Anything that happens with the file after that point is completely outside of your application's control because the file is being managed by another process.
You would need to use either AppleScript/Apple Events or the Accessibility Framework to control whatever application currently has the file open and ask it to close the file, but there is no guarantee that it will do so.
The only way to guarantee that you will be able to close the file is to open it in your app. Obviously, this is impossible if you need to open a variety of diverse and possibly proprietary file types.

the action can't be completed because the folder or a file in it is open in another program

When deleting a folder that contains a file that is in use, it is common to see the following Windows 7 message,
"The action can't be completed because the folder or a file in it is open in another program."
I commonly have 10-20 programs open, 30-40 folders open, etc. In short, I have many executables running and many windows explorers open.
Does anyone know a simple trick to determine which program is using the file?
Does anyone know a simple trick to determine which file is blocking the delete operation?
This information would be highly useful to display in the Windows 7 'folder in use' dialog, but it is missing.
Consequently I have to close many of my open applications and folders to complete the delete operation. This is annoying because I have to re-open them after deleting them.
Have you seen this other question or this one?
I use to run ProccessExplorer and Find for the blocked folder.
Closing the application Malwarebytes allowed me to delete what I needed to via Windows Explorer.

Redirect default program to another program when a file opens in Windows OS

This is only under windows env.
As I know windows os identifies associated application of a particular file by file extension.
Like wise each file (binary) starting with corresponding symbols ("starting symbols"). For an example .JPG starts with ÿØÿà. Let say I open this .JPG file in a Hex editor or a Text editor and then I change that starting symbols into another file type. for an example I can change ÿØÿà to .Eߣ (.mkv). So when I double click on the .JPG the Windows Photo Viewer says there are some errors or similar message. So I need to get some information about the application that tries to open that kind of a file. If I can, I need to open that file using the application that associated with "starting symbols".
Briefly when I open .JPG I need to open a default video player .mkv files. But It may not work for this example. Because I changed only the "starting symbols" of my .JPG.
Please give me any idea to do this.
Thanks!
When you encrypt the file, give it a new extension. e.g. Picture.jpg becomes Picture.encrypted-jpg. You then register as the handler for encrypted-jpg, decrypt the file, then launch the normal jpg handler.
When the shell is asked to perform a verb on a file, the shell does not use the contents of the file to determine which app to pass it to. The file extension is what determines how the file will be treated.
You wish to use the contents of the file to influence which app processes a shell verb. In order to do so you would need to create a launcher app that reads the file header and then decides which app to pass the file on to. You would assign your launcher app as the handler app for all file extensions that you were interested in.
Although you could do this, it would be much easier just to set the file extension appropriately.
The proper way to do this sort of thing is to replace the files with reparse points.
The downside is that this involves writing a file system filter driver, i.e., an operating system extension, which is a whole level of trouble above and beyond ordinary application programming. (Since Windows already does file encryption, I doubt it would be worth the effort.)

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