| I'm not going to argue that UNIX got everything right because I don't believe that to be the case either but I don't agree with those specific points: > This means that you can’t send an object and the code for the class definition necessary to implement the object. To some degree you can and I do just this with my own shell I've written. You just have to ensure that both ends of the pipe understands what is being sent (eg is it JSON, text, binary data, etc)? Even with typed terminals (such as Powershell), you still need both ends of the pipe to understand what to expect to some extent. Having this whole thing happen automatically with a class definition is a little optimistic though. Not least of all because not every tool would be suited for every data format (eg a text processor wouldn't be able to do much with a GIF even if it has a class definition). > You can’t send pointers into another process’s address space. Good job too. That seems a very easy path for exploit. Thankfully these days it's less of an issue though because copying memory is comparatively quick and cheap compared to when that handbook was written. > You can’t send file handles Actually that's exactly how piping works as technically the standard streams are just files. So you could launch a program with STDIN being a different file from the previous processes STDOUT. > or tcp connections You can if you pass it as a UNIX socket (where you define a network connection as a file). > or permissions to access particular files or resources. This is a little ambiguous. For example you can pass strings that are credentials. However you cannot alter the running state of another program via it's pipeline (aside what files it has access to). To be honest I prefer the `sudo` type approach but I don't know how much of that is because it's better and how much of that is because it's what I am used to. |
> Actually that's exactly how piping works
Also SCM_RIGHTS, which exists exactly for this purpose (see cmsg(3), unix(7) or https://blog.cloudflare.com/know-your-scm_rights/ for a gentler introduction and application).
That's been around since BSD 4.3, which predates the Hater's Handbook 1ed by 4 years or so.