--- a/Queue.st	Wed Jun 12 13:35:16 1996 +0200
+++ b/Queue.st	Sat Jun 22 18:52:25 1996 +0200
@@ -17,7 +17,7 @@
 	category:'Collections-Ordered'
 !
 
-!Queue class methodsFor:'documentation'!
+!Queue  class methodsFor:'documentation'!
 
 copyright
 "
@@ -55,7 +55,7 @@
 "
 ! !
 
-!Queue class methodsFor:'instance creation'!
+!Queue  class methodsFor:'instance creation'!
 
 new
     "return a new queue with space for some elements"
@@ -143,6 +143,29 @@
 
     (tally == 0) ifTrue:[^ nil].
     ^ contentsArray at:readPosition.
+!
+
+removeLast
+    "return the last value in the queue; 
+     Return nil, if the queue is empty"
+
+    |value pos "{ Class: SmallInteger }"|
+
+    (tally == 0) ifTrue:[^ nil].
+
+    pos := writePosition.
+    pos == 1 ifTrue:[
+        pos := contentsArray size
+    ] ifFalse:[
+        pos := pos - 1.
+    ].
+
+    value := contentsArray at:pos.
+    writePosition := pos.
+    tally := tally - 1.
+    ^ value
+
+    "Created: 22.6.1996 / 18:49:41 / cg"
 ! !
 
 !Queue methodsFor:'enumerating'!
@@ -200,8 +223,8 @@
     ^ tally
 ! !
 
-!Queue class methodsFor:'documentation'!
+!Queue  class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic2/Queue.st,v 1.17 1996-05-18 15:32:39 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic2/Queue.st,v 1.18 1996-06-22 16:52:09 cg Exp $'
 ! !

--- a/SharedQueue.st	Wed Jun 12 13:35:16 1996 +0200
+++ b/SharedQueue.st	Sat Jun 22 18:52:25 1996 +0200
@@ -17,7 +17,7 @@
 	category:'Kernel-Processes'
 !
 
-!SharedQueue class methodsFor:'documentation'!
+!SharedQueue  class methodsFor:'documentation'!
 
 copyright
 "
@@ -123,6 +123,38 @@
     "Modified: 16.12.1995 / 13:47:11 / cg"
 !
 
+removeLast
+    "return the last value in the queue; if it its empty, wait 'til
+     something is put into the receiver.
+     When the datum has been removed, signal space-availability to
+     writers"
+
+    |value ok|
+
+    ok := false.
+    [ok] whileFalse:[
+        [tally == 0] whileTrue:[
+            dataAvailable wait
+        ].
+        accessProtect critical:[
+            "
+             this check is needed, since another process may
+             have read the value in the meantime ...
+            "
+            tally == 0 ifFalse:[
+                value := super removeLast.
+                tally == (contentsArray size - 1) ifTrue:[
+                    spaceAvailable signal
+                ].
+                ok := true
+            ]
+        ]
+    ].
+    ^ value
+
+    "Created: 22.6.1996 / 18:50:12 / cg"
+!
+
 writeSemaphore
     "return the semaphore which is signalled when the queue has space
      for writing."
@@ -143,8 +175,8 @@
     spaceAvailable := Semaphore new
 ! !
 
-!SharedQueue class methodsFor:'documentation'!
+!SharedQueue  class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic2/SharedQueue.st,v 1.15 1996-04-25 16:54:09 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic2/SharedQueue.st,v 1.16 1996-06-22 16:52:25 cg Exp $'
 ! !