Linux

No

I always try to avoid these, unless the application I'm installing has it's own package management functionality, like Rustup or Nix. Everything else should be handled by the system package manager.

I usually just take a look at the code with a get request. Then if it looks good, then run manually. Most of the time, it's fine. Sometimes there's something that would break something on the system.

I haven't seen anything explicitly nefarious, but it's better to be safe than sorry.

And don't forget to sudo!

Just use a VM or container for installing software. It can go horribly wrong in a isolated place.

What does curl even do? Unstraighten? Seems like any other command I’d blindly paste from an internet thread into a terminal window to try to get something on Linux to work.

| sh stands for shake head at bad practices

Most packages managers can run arbitrary code on install or upgrade or removal. You are trusting the code you choose to run on your system no matter where you get it from. Remember the old bug in ubuntu that ran a rm -rf / usr/.. instead of rm -rf /usr/... and wiped a load of peoples systems?

Flatpacks, Apparmor and snaps are better in this reguard as they are somewhat more sandboxed and can restrict what the applications have access to.

But really if the install script is from the authors of the package then it should be just as trustworthy as the package. But generally I download and read the install scripts as there is no standard they are following and I don't want them touching random system files in ways I am not aware of or cannot undo easily. Sometimes they are just detecting the OS and picking relevant packages to install - maybe with some thrid party repos. Other times they mess with your home partition and do a bunch of stuff including messing with bashrc files to add things to your PATH which I don't like. I would never run a install script that is not from the author of the application though and be very wary of install scripts from a smaller package with fewer users.

Just direct it into a file, read the script, and run it if you're happy. It's just a shorthand that doesn't require saving the script that will only be used once.

I also feel incredibly uncomfortable with this. Ultimately it comes down to if you trust the application or not. If you do then this isn't really a problem as regardless they're getting code execution on your machine. If you don't, well then don't install the application. In general I don't like installing applications that aren't from my distro's official repositories but mostly because I like knowing at least they trust it and think it's safe, as opposed to any software that isn't which is more of an unknown.

Also it's unlikely for the script to be malicious if the application is not. Further, I'm not sure a manual install really protects anyone from anything. Inexperienced users will go through great lengths and jump through some impressive hoops to try and make something work, to their own detriment sometimes. My favorite example of this is the LTT Linux challenge. apt did EVERYTHING it could think to do to alert that the steam package was broken and he probably didn't want to install it, and instead of reading the error he just blindly typed out the confirmation statement. Nothing will save a user from ruining their system if they're bound and determined to do something.