💾 Archived View for bbs.geminispace.org › u › clseibold › 11921 captured on 2023-12-28 at 16:49:01. Gemini links have been rewritten to link to archived content
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Re: "How to open files and URLs with the preferred application..."
@lufte For the filetypes on Windows, there is AssocQueryString.
Don't let the terrible Win32 MSDN docs scare you too much, it's simpler than the docs make it look, lol. Here's an example usage from StackOverflow:
— https://stackoverflow.com/a/17773402
However, the above will only give you what the application is. To actually open the application, I believe you need to then use another Win32 API call, but I don't know which one.
More simply, you could also just call ShellExecute, although I wouldn't recommend this:
— https://learn.microsoft.com/en-us/windows/win32/api/shellapi/nf-shellapi-shellexecutew
Finally, for macOS, there are APIs in the Launch Services stuff (whatever that is, lol). Here's the docs for LSOpenCFURLRef, which is likely what you want, and this is for macOS 10.0+:
— https://developer.apple.com/documentation/coreservices/1442850-lsopencfurlref
There is also a deprecated LSCopyDefaultApplicationURLForURL which is just for macOS 10.10 through 12.0:
— https://developer.apple.com/documentation/coreservices/1448824-lscopydefaultapplicationurlforur
Nov 21 · 5 weeks ago
Taking notes here. The implementation from open-python looks simple enough too.
🚀 clseibold · Nov 21 at 22:46:
@lufte I do have to say that when starting subprocesses like this, one does need to consider security. For example, the Python subprocess.call() and subprocess.run() functions can take a Shell argument that, when set to true, calls into the shell, which can be vulnerable to command injection (which is similar to sql injection, but for shell commands). It's the same for C's system() and exec() functions too.
There are also performance implications with subprocesses. Subprocesses are heavier and take more resources than API calls.
While not perfect, you can usually detect the OS in use from an env var (again, not always relioable but pretty good) and then switch on the OS using xdg-open on linux, open on osx, etc. (providing a fallback as just downloading the file when a program is not available or there is not a handler for a filetype).
👻 mediocregopher · Nov 22 at 07:19:
If a Linux system doesn't have xdg-open, is there some alternative URL opener it might have? I've only ever seen xdg-open...
🚀 clseibold · Nov 22 at 08:00:
@sloum I never thought about detecting the OS with an environment variable. Usually I do it with compile-time statements (Odin's `when ODIN_OS == .Windows {`), or with the language's runtime variables (I think Golang does it this way).
🚀 clseibold · Nov 22 at 08:03:
@mediocregopher I believe gnome-open is also a thing, but I am not experienced in doing that type of stuff in linux, so I don't know much about it, lol. Xdg-open is very common in linux, so it's probably just fine to use it. Don't mind my bitterness towards linux too much, I just hate that Unix's potential went to waste with Linux's unstandardized and frantic approach :D
Update: Apparently xdg-open is just a wrapper around multiple desktop environments, including gnome-open and `gio open`. Does anyone know if xdg-open requires a DE to work, or if it also works in terminal-only environments?
Update 2: I've also found an exo-open which is the gnome-open equivalent for XFCE. KDE uses kde-open. All three (exo-open, kde-open, and gio) are wrapped with xdg-open.
👻 mediocregopher · Nov 22 at 08:37:
@clseibold thank you for doing my research for me :) I'll remain contented with xdg-open then.
re: working in a terminal-only environment, I can't think one would.... what the behavior even be? Run a process as a background job in the current shell?
🚀 clseibold · Nov 22 at 09:32:
@mediocregopher Personally, I would expect that a system where you can specify default applications for different filetypes and URIs be standardized in the OS APIs, and that a cli `open` command would call out to this API and open the file/URI with that default application as a subprocess of the shell. I believe this is essentially what macOS does (macOS does have an `open` command), and it's also what Windows does, and Haiku afaik. Because it would be a part of the OS, it would work in a terminal-only environment and a graphical environment, and there'd be one standard across all variants/extensions of the OS.
@clseibold Yes, most languages will have some module for OS detection. You can check against `$OSTYPE`, which I believe should be available for pretty much every major system. Subprocessing out to `uname` can also be useful for this purpose. I can't remember which I did... my use case was in a makefile (for gnu make, since bsd make does not support if statements). So I think it makes sense in a makefile (again, targeting a non-bsd system) but may not have the same use case in a more full featured language/environment.
How to open files and URLs with the preferred application in multiple operating systems? Not really related to Gemini, but I need to implement a way in my Gemini client to open unsupported URLs and files on their proper apps, mostly on Linux but ideally in other systems as well. Fellows who have written their own clients, how did you do it?