open command misleading error message

[Tom Goddard]

The open command gives a misleading error message when opening a file that does not exist. It should simply say the file does not exist. Here is what it says now:

open /something/somewhere
.........................
^{Missing or unknown file type}

[Greg Couch]

open xyzzy
now gives the error:
Missing filename suffix

open xyzzy.aaa
now gives the error:
Unrecognized filename suffix

And {{{open xyzzy.pdb}}
now gives the error:
[Errno 2] No such file or directory: 'xyzzy.pdb'