Added labels start and exit to system header files

include/apple1.h02

@@ -46,3 +46,7 @@ void newlin();  //Advance cursor to beginning of next line
 char polkey();  //Poll Console for character
 char putchr();  //Print ASCII character to Console
 char getchr();  //Wait for character from Console
+
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/apple2.h02

@@ -29,7 +29,7 @@ char kbd; //Keyboard Data Register
 char akd; //Keyboard Strobe Register
 
 /* Monitor Subroutines */
-void prbyte(); //Print Accumulator as Hexadadecimal number
+void prbyte(); //Print Accumulator as Hexadecimal number
 void prhex();  //Print Low Nybble of Accumulator as Hex Digit
 
 /* System Subroutines */
@@ -43,3 +43,7 @@ void newlin(); //Advance cursor to beginning of next line
 char polkey(); //Poll Console for character
 char putchr(); //Print ASCII character to Console
 void setpos(); //Set Cursor Position
+
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/c64.h02

@@ -33,3 +33,7 @@ void prbyte(); //Print Accumulator as Hexadadecimal number
 void prhex();  //Print Low Nybble of Accumulator as Hex Digit
 char getchr(); //Wait for character from Keyboard
 void setpos(); //Set Cursor Position
+
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/header.h02

@@ -45,3 +45,7 @@ void prbyte(); //Print Accumulator as Hexadadecimal number
 void prhex();  //Print Low Nybble of Accumulator as Hex Digit
 char getchr(); //Wait for character from Console
 void setpos(); //Set Cursor Position
+
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/oric.h02

@@ -25,3 +25,7 @@ void newlin();    //Advance cursor to beginning of next line
 char putchr();    //Print ASCII character to Console
 void prbyte();    //Print Accumulator as Hexadadecimal number
 void prhex();     //Print Low Nybble of Accumulator as Hex Digit
+
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/py65.h02

@@ -34,3 +34,7 @@ void delchr(); //Delete previous character
 char putchr(); //Print ASCII character to Console
 void prbyte(); //Print Accumulator as Hexadadecimal number
 void prhex();  //Print Low Nybble of Accumulator as Hex Digit
+
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/py65min.h02

@@ -16,3 +16,6 @@ char getchr(); //Wait for character from Console
 char getkey(); //Read ASCII character from Console
 char putchr(); //Print ASCII character to Console
 
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/vic20.h02

@@ -33,3 +33,7 @@ void prbyte(); //Print Accumulator as Hexadadecimal number
 void prhex();  //Print Low Nybble of Accumulator as Hex Digit
 char getchr(); //Wait for character from Keyboard
 void setpos(); //Set Cursor Position
+
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/vic3k.h02

@@ -32,3 +32,6 @@ char putchr(); //Print ASCII character to Console
 void prbyte(); //Print Accumulator as Hexadadecimal number
 void prhex();  //Print Low Nybble of Accumulator as Hex Digit
  
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System

include/vic8k.h02

@@ -35,3 +35,7 @@ void clrscr(); //Clear the Screen
 char getsiz(); //Get Screen Size
 char getpos(); //Get Cursor Position
 void setpos(); //Set Cursor Position
+
+//System Labels
+start:  //Start of Code
+exit:   //Return to Operating System