Oracle's RMAN should come back with a prompt or at least the welcome banner when it is started. So I was pretty amazed when I found out that all attempts to start rman on a Suse system did result in - - - nothing at all :-(
Of course the first thing I tried was a different login, different database, etc.
Then I thought - as I had similar problems on this machine that there might be a problem with a path. However I was 110 % sure that the oraenv did its job.
which rman revealed:
which seems to be RosettaMan, a system to reformat man pages. I didn't know that RMAN was capable of doing this, too ;-)