Multiple blocks in MDI

[Fred Proctor <proctor-at-cme.nist.gov>]

Ray et al,

I looked at the RS-274-NGC spec, which I have on paper only, and I saw
that the end-of-block (EOB) character is a line feed, 0x0A, and also
that a semicolon will be displayed as the EOB. I talked with Tom Kramer,
the writer of the interpreter, and he agreed that splitting the line
into blocks at the GUI is the best place to do this. He wrote:

>
It would be very hard to put multiple blocks on one line into the
interpreter itself, because of its alternating read/execute cycle.
It should be a piece of cake to do this from your MDI interface,
though, by picking out the blocks of text between the semicolons
and calling first read then execute for each block.
Remember that in the new interpreter, rs274ngc_read is called
with a non-null string for doing MDI. If I were programming it,
I might try replacing each semicolon with NULL, effectively breaking
the string into substrings. Might have to take strlen before doing
that to know where the real end is when it is peppered with NULLs.

The interpreter itself don't know nuffin 'bout no semicolons, as you
observed. That bit from the spec about semicolons probably was intended
to allow multiple blocks on one line, but you sure can't tell that by
reading the spec.
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--Fred