We only use that language because it's an order of magnitude easier to explain to novice computer users, and because as you stated, the problem still hasn't been fixed at the OS permissions / UI level. A modern OS lets us do that because lots of users are the sole user of their PC and do not understand the idea of permissions.
People understand that webapps are safe, because they have less permissions.
That really isn't telling the whole story at all. Webapps have their own problems -- like no ownership or control over your data.
What I find funny is that this piece of software actually tells you more about what it does than software you pay money for and even uninstalls itself, after it is not needed anymore. It's kinda weird how malware is better quality than most other software.
But sometimes you want to just "open" a file. The fact that your computer may choose to save it is an implementation detail. In fact, most systems don't actually 'save' it in many senses of the word. Instead they write it to the file system in a way that indicates that it may be removed at any time without notifying the user. In fact, on Linux (I can't speak to any other OS), it is common for these temporary files ne…
In a way, that's worse! You'll have someone "open" a file, maybe make some edits to it, save it -- and it won't indicate a problem with that because it's considered as a file on disk somewhere -- and then when they go to send it, they can't find it and it may have been overwritten / deleted.
If the file is opened read-only, then programs should fall back to save as. Unfourtuantly, the only standard way to signal read-only is with file permisions. This will work, but many programs would likely have report a permisions error prior to the save as. Also it will cause problems for programs that transparently modify the file on disk while viewing.
I suppose you could hard code the read only parameter into the command that is used to execute the external program. Or have the external programs check if they are in a tmp-directory.