🚀 go-pugleaf

>> Are values in ASN.1 character string types that by default include no Cn
>> sets (e.g. Graphic String) permitted to load a Cn set via an escape
>> sequence?  I should appreciate a reference to appropriate defining
>> text.

Simon Walton writes:

>   When using basic encoding rules the representation for
> GraphicString may contain escape sequences to invoke Cn
> character sets.

Was this just a slip of the finger?   My copies of  X.208  &  X.209  say
that GraphicString may contain escape sequences to invoke _Gn_ character
sets.

My summary of the standards:

Graphic  Strings  may  not  contain  control  characters.    Their   BER
representations  may  contain  ESCape  sequences,  but  only  to specify
different graphic character sets.

In general, string types may only contain the  characters  specified  in
X.208; their BER representations may contain only the representations of
those  characters,  including  whatever  ESCape/control  sequences   are
necessary to set the context for those representations (according to ISO
2022 etc).

(References: X.208 table 6 (near section 31.2); X.208 section 31.6;
X.209 table 2 (near section 23.5.2); X.209 section 23.5.1)

I'm sure somebody will correct me if I'm wrong...

David Stone
<dstone@wl9.prime.com>
speaking for myself, and not Prime Computer.