Added reinitializer package

NEWS

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 version 0.6
+* New s48 library: reinitializer
 * New scsh libraries: file-mode
 * New s48 libraries: SRFI-34/SRFI-35 exceptions and conditions, SRFI-10
 
+
 version 0.5 2003-11-19
 * New s48 libraries: procedure-tables.
 * New scsh libraries: tiff.

s48/heap-images/AUTHORS

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+Martin Gasbichler

s48/heap-images/BLURB

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+reinitializers: Specify code to run on scsh's startup

s48/heap-images/README

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+The package REINITIALIZERS allows the user to specify code that is
+executed on every start of scsh, provided a heap image containing the
+reinitializer is used.
+
+Procedures:
+
+(make-reinitializer thunk) -> reinitializer
+
+Creates a reinitializer that runs THUNK on every start of the system.
+The returned reinitializer should be saved in a global variable to
+ensure that it is reachable for the garbage collector and saved in the
+heap image.

s48/heap-images/interfaces.scm

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+(define-interface reinitializers-interface
+  (export make-reinitializer
+          reinitializer?))
+  

s48/heap-images/packages.scm

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+(define-structure reinitializers reinitializers-interface
+  (open scheme
+        define-record-types
+        records)
+  (files reinitializer))

s48/heap-images/reinitializer.scm

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+(define-record-type reinitializer :reinitializer
+  (make-reinitializer thunk)
+  reinitializer?
+  (thunk reinitializer-thunk))
+
+(define-record-discloser :reinitializer
+  (lambda (r)
+    (list 'reinitializer (reinitializer-thunk r))))
+
+(define-record-resumer :reinitializer
+  (lambda (r)
+    ((reinitializer-thunk r))))