>However I haven't seen any justification as to why the ksh93-style >interface is to be preferred over any of the other possible interfaces.
That's an interesting argument to bring to the PSARC meeting. But clearly that has already happened, so we're a bit late. Clearly, we have not analyzed the run-time behaviour of the new commands; we would have found the bug in ksh93 (~()) and we would have found that the ksh93 wants to open ".paths" in every element of $PATH. I think we should fix that: we need to do that for the other shell scripts also (alias, bg, etc) and it's easier to keep sleep as it now is. As for /bin/basename: clearly the optimized version exist for a reason; that is clearly not the case for sleep. Clearly, making basename a script would be wrong. But it might be different in other cases, specifically when the built-in command is faster than the standard Solaris command. Casper