[9fans] allowing space (ASCII 0x20) in file names

[G. David Butler gdb@dbSystems.com]

From: "Tom Duff" <td@pixar.com>

>It's ludicrous to make an incompatible change like this with, as you noted,
>such far-reaching consequences, just for one weird little application.

NNTP (look at the new draft rfc1036)? IMAP? CIFS?  These are not "little"
nor "weird" applications.

>If your application doesn't like the names the file system gives it,
>keep a little name-mapping table somewhere and write open and create
>routines that use it.

How do you map a dense UTF-8 encoding on another with 255 octets
to 27?  If there is a character that can be used as a ubiquitous
terminator (like 0x7f perhaps?) then

a-very-long-file-name-that-is-much-longer-than-27-octets

could be

a-very-long-file-name-that-/is-much-longer-than-27-octe/ts{0x7f}

or you could trust MD5 and turn it into 16 bytes mapped to (16/3)*4=24
base64 characters.  But md5 is only one way so you have to create a
file of mappings (your suggestion).  How do you update a file without
file locking by 100's of cpu servers?  That would be very hard with
exclusive access files that don't block (that can be fixed too)!
(BTW: There are also 100's of file servers.)  Also the failure
scenarios are crazy.

We are told Plan9 is dead.  Inferno is alive.  The last time I
talked to Lucent about licensing, they will not license Plan9 for
re-distribution.  So I'm alone anyway if I use Plan9.  It is *much*
easier to change the OS to host the application than it is to twist
the application to live with the OS.  Remember INN, CYRUS and SAMBA
are applications that already exist...

I'm open to suggestions...

Thanks again.

David Butler
gdb@dbSystems.com