Philippe Verdy scripsit: > Are there still now platforms where storage bytes are not octets but nonets? As others have written, the PDP-10/PDP-20 hardware is long obsolete. However, there are still emulators running on modern 32-bit and 64-bit hardware. That was the point of the remark about "the number of 36-bit hosts on the Internet has grown by an order of magnitude", viz. from about one to about ten.
> This means that the interchange would require to send 2 octets to represent > each 9-bit byte without loosing data, or to use a complex bit pattern to > pack sequences of height 9-bit bytes into sequences of nine 8-bit bytes, and > with a way to interpret the last sequence [...]. A number of such conventions were used on actual PDP-10s/20s, including: 5 octets interpreted as 36 bits with 4 padding bits, 5 octets interpreted as 32 bits with 4 bits lost, 5 octets interpreted as 5 7-byte characters with the extra bit either lost or stuffed into the last octet, 6 octets interpreted as 6 6-bit characters, and 9 octets interpreted as two consecutive 36-bit words. > What will happen then to a plain-text coded with UTF-9, and that is sent > through FTP? FTP has two modes, text and image. Today this is used to decide whether to translate line-ends to and from the on-the-wire standard of CR+LF or not, but on the PDP-10/20 it was used to discriminate between sending 35 bits in 5 octets (the standard for ASCII text) and sending 72 bits in 9 octets. -- "You know, you haven't stopped talking John Cowan since I came here. You must have been http://www.reutershealth.com vaccinated with a phonograph needle." [EMAIL PROTECTED] --Rufus T. Firefly http://www.ccil.org/~cowan
