Making XPL written in Xy4 compatible with Xy3 [was Re: young and notabene]

[cld@xxxxxxxx (Carl Distefano)]

Reply to note from "Young For Life Products, Ltd"
 Sun, 21 Oct 2001 10:32:53 -0500

> Morris, what a good idea. I don't have XY3 anymore,
> unfortunately. Is there somewhere I can download it still?

You don't need Xy3 to write a program that will run in Xy3. Just
write it in Xy4, using Xy3 conventions. It will run, and you'll be
able to debug it, in Xy4. If there are debugging issues specific to
v3, interested Xy3 users will tell you about them.

What exactly does your program do? I'm not clear on that.

If you're ever unsure about where your Xy4 program directory is,
simply command VA/NV $ED. This returns the full path to EDITOR.EXE.

When you want to know where *somebody elses's* Xy4 directory is --
and often you do if you're writing "public" XPL -- use 
(avilable in v4+ only). This returns the fully-qualified path to
EDITOR.EXE, for example, in your system, D:\XY4\EDITOR.EXE. To get
the directory name, save  to a Save/Get and parse the
contents of that Save/Get into two strings, directory and filename.

The Jumbo U2 has a routine, GETPATH, that does that parsing job.
Feed it any fully-qualified filename in Save/Get 50 and it returns
the directory portion (minus the final backslash) in S/G 50. So,
for example, to put the directory that contains EDITOR.EXE into S/G
50, you'd write: >JM 2.GetPathQ2 . You can then use
S/G 50 to locate and use other files in the same directory. For
example,
;*;
BX exist \underln.exe ONQ2 )>;*;
BX do/nv/x \underln.exe ONQ2 ;*;

--
Carl Distefano
cld@xxxxxxxx
http://users.datarealm.com/xywwweb/