On Apr 11, 9:49 pm, m_l_g3 <m_l...@[EMAIL PROTECTED]
> wrote:
> On Apr 11, 8:28 pm, Bruce McFarling <agil...@[EMAIL PROTECTED]
> wrote:
>
> > On Apr 11, 7:43 am, m_l_g3 <m_l...@[EMAIL PROTECTED]
> wrote:
>
> > > One more thing to clarify: can the file reference returned by
ANCHORED
> > > or LIB-ANCHORED be overwritten by S" ?
>
> [...]
>
>
>
> > So it may well be that S" does not exist in the dictionary until it
> > has been loaded from the LIB-ANCHORED filespace by a file that did a:
>
> > [UNDEFINED] S" [IF] ( ... define S" ) [THEN]
>
> > process. And since the definitions of ANCHORED and LIB-ANCHORED leave
> > the buffer opaque, there is no way to *ensure* that the three have a
> > shared buffer.
>
> > Therefore, since "maybe they do and maybe they don't" is a portability
> > headache, required because existing practice "in some cases does and
> > in some cases doesn't", in this case, where I'm going to be putting
> > these into Linux gforth and CP/M hForth and z80 Camel and C64
> > VolksForth for my own personal use, I'm going to start out avoiding
> > the problem all together and being explicit:
>
> > 1. Yes, LIB-ANCHORED and ANCHORED may have a common absolute file
> > reference buffer. On small Forth systems, they are *likely* to have a
> > common absolute file reference buffer, to reduce the codespace
> > footprint of both the buffer and the words manipulating it (+); and
>
> 1a. The buffer is transient, its addresses and contents may
> become invalid after any of the conditions mentioned
> in 3.3.3.6 Other transient regions.
>
> > 2. No, there is no sharing between the LIB-ANCHORED and ANCHORED
> > absolute file reference buffer and any buffer provided for a command-
> > line ``S"''.
>
> Personally I do not see any problem with that the S" buffer may not
> exist. There is even no need to define a word for that buffer, it may
> be just PAD /PAD +
>
> I would prefer to assume that ANCHORED always rewrite the interpreted
> S" buffer. These buffers are anyway transient, no problem if they are
> *one* transient buffer.
>
> So,
>
> 2a. In addition, the buffer may be invalidated after execution of
> 11.6.1.2165 S"
> in interpretation state.
2b. ANCHORED _may_ return the same address and length as were passed
to it, so if the argument string was in a transient buffer, the
result may also be in that transient buffer.
INFORMATIVE we must allow the no-op implementation like
: ANCHORED ;
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