world management and patches

[Barry Margolin <barmar@THINK.COM>]

    Date: Mon, 20 Jun 88 13:37 EDT
    From: DLW@alderaan.scrc.symbolics.com (Daniel L. Weinreb)

	Date: Mon, 20 Jun 88 12:15 EDT
	From: barmar@Think.COM (Barry Margolin)

	What I need is a way to put these patches somewhere and tell the system
	"if anyone loads the C system, and the version number is less than
	XX.YY, AUTOMATICALLY load these patches afterward."

    You say that your worlds are configured to load certain patches
    automatically when they boot.  Can't you just extend this mechanism to
    have them do the equivalent of ":Load Patches Color" when the Color
    system is loaded?  Then just put the patches somewhere on disk such
    that their logical pathnames map to that place, and the patches will
    get loaded.  Your extension could either only be present in Color
    worlds, or it could be present in all worlds and check at runtime
    for the presence of Color, using sct:get-system-version.

When Customer Support mails me a fixed version of something in the Color
system, how can I make it be loaded by "Load Patches Color"?  I can't
make defsystem-style patches to the Color system, because I'm not at the
maintaining site.  Even if I override that, I then have a problem if
Symbolics sends me an ECO tape that includes patches to that system,
since I will have used a minor version number that duplicates one of
yours; this is the reason for the warning when I try to patch a system
not maintained at this site.

                                                barmar