"File types"

[Chuck Guzis]

On 8/30/2006 at 10:04 PM Hans Franke wrote:

>You may form endless variations of these concepts - as many
>as you got time on your hand, and belive me, the last 50 years
>gave developers quite some time to invent the world over and over.

How about CDC 6000 character records--terminated by 12 bits of zero but
only if in the low-order 12 bits of a 60-bit word?  Otherwise, 00 in any
other position signified one or more colons.   That gave a lot of
programmers fits--there were double-colon sequences that could not be
represented.   Punch two colons as the 8th and 9th characters of an input
record and see two colons read as input.  Move them over one character and
see an end-of-line instead.

Or, the hardware could design a special character or condition, such as a
tape IRG, or a 1620 record or group mark--that did not represent data on
the machine.

There's also one other interesting one that I've seen--the first character
of a record specifies the ending delimiter:  "XorX", for the string "or".

Cheers,
Chuck