add library stubs for openbsd: device (vm support coming soon)

FossilOrigin-Name: acfaa8caead4e0c4229bdf48180ad52cb99330da3f7dbd315477c59ad3a7792b

RELEASE-NOTES

@@ -46,13 +46,17 @@
   - stack comments & descriptions are now part of the standard
     system image
   - add `d:words-missing-details`
-  - add `describe`
+  - add `add-description`
 
 - library
 
   - added "tob", a text output buffer
   - added "c:get/ext", for reading keys and returning unique
     codes for arrows
+  - added "openbsd", for interacting with an openbsd-specific
+    i/o extension
+    - adds "openbsd:pledge"
+    - adds "openbsd:unveil"
 
 - retro-compiler
 

interface/descriptions.retro

@@ -3,9 +3,10 @@
   d:lookup dup n:-zero? [ d:descr &s:keep dip store ] &drop-pair choose ;
 'add_a_description_to_a_word 'd:set-description d:set-description
 
-:describe (:s-)
+:add-description (:s-)
   s:keep d:last d:descr store ;
-  'add_a_description_for_the_most_recently_defined_word describe
+  'add_a_description_for_the_most_recently_defined_word
+  add-description
 ~~~
 
 ~~~

library/openbsd.retro

@@ -0,0 +1,16 @@
+Extensions relating to OpenBSD-specific functionality
+
+~~~
+:io:openbsd (:...n-)
+  ;
+'For_use_on_OpenBSD_only:_invoke_host_specific_functionality.
+add-description
+
+:openbsd:pledge (:s-) ;
+'For_use_on_OpenBSD_only:_invoke_pledge()_with_the_provided_string.
+add-description
+
+:openbsd:unveil (:s-) ;
+'For_use_on_OpenBSD_only:_invoke_unveil()_with_the_provided_string._A_pointer_to_0_can_also_be_passed.
+add-description
+~~~