“Do one thing and do it very well” is the UNIX philosophy after all; if you’re 99% likely to just create that missing file after you get a file not found error, why should
touchwaste your time?with this logic, any command that moves, copies or opens a file should just create a new file if it doesn’t exist
and now you’re just creating new files without realising just because of a typo
Because now touch does two things.
Without touch, we could “just” use the shell to create files.
: > foo.txtTouch does one thing from a “contract” perspective:
Ensure the timestamp of <file> is <now>
Systemd also does one thing from a contract perspective: run your system
Does it do it well, though?
Oh no.
:(
But this directly goes against that philosophy, since now instead of changing timestamps it’s also creating files
You can pass
-cto not create a file, but it does go against the philosophy that it creates them by default instead of that being an optionEDIT: Looking closer into the code, it would appear to maybe be an efficiency thing based on underlying system calls
Without that check, touch just opens a file for writing, with no other filesystem check, and closes it
With that check, touch first checks if the file exists, and then if so opens the file for writing
