Re: NUL to terminate strings; was reinventing ASCII?

"Morris Dovey" <mrdovey@[EMAIL PROTECTED]
> wrote in message
news:47D55539.F04969E6@[EMAIL PROTECTED]
> James Harris wrote:
>
> > I suppose the bit missing from what I said above is that the
> > C concept of a string being an array (of char) allows nowhere for a
> > length prefix. If it is an array of char then all elements should be
> > of type char. I suppose the libraries could just ignore this
> > requirement (could they?) but then would have to agree on how many
> > bytes made up the length and in what order they existed. Hmm....
>
> The Stratus C compiler provides both BCPL and C strings. IIRC,
> the length component of the BCPL-PL/I style string is a 16-bit
> unsigned value.
>

It's been a few years, so I no longer recall the size.  But, the
interesting
aspect Stratus VOS PL/1 strings was that the length at the front of the
string (and whatever else was there... size?) was a header of fixed size.
IIRC, that was true of PL/1's struct's too.  I.e., for C, the header with
the length could be 1) at a negative offset from the start of the string
or
2) an offset for the size of the header could be added to C's char pointer
"to the first of the objects making up the array", i.e., "decayed into"
pointer.  One could implicitly assume that array[length]=='\0'... although
no null character is actually there.  I'm not sure about C compliance
comlications...


Rod Pemberton