[codedokode]

The problem with replacing exec/fork is that you usually want to configure new process: for example, set up signal handlers, close or open FDs, switch namespaces, setup seccomp, adjust permissions. And all the system calls to do it apply only to the current process and you need something to replace them. The proposal in the article was to create a new API for this.

My idea is that we could make a new syscall, for example "spawn", that creates a new empty process, loads some lightweight "loader" into it, and passes arbitrary configuration data. The loader configures the process and exec()'s the main program. This allows to avoid forking the memory and keep existing APIs, but still requires to fork file descriptors and other things.

[nyrikki]

Luckily someone with a time machine saw your post and added it to POSIX.1-2001 :)

(Sorry if you weren't joking) but yes, posix_spawn() has been a thing and in glibc fork is just a alias to clone()

Not exactly that OP idea, but fork/exec is legacy really.

[MayCXC]

other people in the thread say that posix_spawn is more or less implemented as a fork+exec wrapper though? it sounds like the idea is more like if there were a separate deferred_fork that made an intermediate "process factory" that let you set up a process without actually creating a new one until the exec. obviously the if() construct would have to be replaced with an in-process handle that mimics calls to the posix api.