Add Atari version of of doesclrscrafterexit().

- Update documentation.
- Update atari.h and apple2.h header files.
- Adapt Atari test/target programs.
- Fix a typo in "div" entry in funcref.sgml.

doc/funcref.sgml

@@ -949,27 +949,7 @@ id="malloc" name="malloc"> may still return <tt/NULL/.
 <tag/Declaration/<tt/unsigned char _is_cmdline_dos (void);/
 <tag/Description/The function returns 0 if the DOS doesn't support command line arguments.
 It returns 1 if it does.
-<tag/Notes/<itemize>
-<item>Many Atari DOSes which don't support command line arguments immediately clear the screen
-and display their menu after a program exits. Therefore it might be difficult to read
-the last messages printed by the program prior to its exit. This function can be used
-to decide if a delay or wait for a key press should be executed when then program
-exits.
-</itemize>
 <tag/Availability/cc65 (<tt/atari/ and <tt/atarixl/ platforms)
-<tag/Example/<verb>
-/* Hello World for Atari */
-#include <stdio.h>
-#include <unistd.h>
-#include <atari.h>
-int main(void)
-{
-    printf("Hello World\n");
-    if (! _is_cmdline_dos())
-        sleep(5);
-    return 0;
-}
-</verb>
 </descrip>
 </quote>
 
@@ -2572,8 +2552,8 @@ used in presence of a prototype.
 <descrip>
 <tag/Function/Divide two ints and return quotient and remainder.
 <tag/Header/<tt/<ref id="stdlib.h" name="stdlib.h">/
-<tag/Declaration/<tt/div_t __fastcall__ div (int numer, int denom);/
-<tag/Description/<tt/div/ divides <tt/numer/ by <tt/denom/ and returns the
+<tag/Declaration/<tt/div_t __fastcall__ div (int number, int denom);/
+<tag/Description/<tt/div/ divides <tt/number/ by <tt/denom/ and returns the
 quotient and remainder in a <tt/div_t/ structure.
 <tag/Notes/<itemize>
 <item>The function is only available as fastcall function, so it may only
@@ -2587,6 +2567,40 @@ ldiv
 </quote>
 
 
+<sect1>doesclrscrafterexit<label id="doesclrscrafterexit"><p>
+
+<quote>
+<descrip>
+<tag/Function/Determines whether the screen is going to be cleared after program exit.
+<tag/Header/<tt/<ref id="atari.h" name="atari.h">, <ref id="apple2.h" name="apple2.h">/
+<tag/Declaration/<tt/unsigned char doesclrscrafterexit (void);/
+<tag/Description/The function returns 0 if the screen won't be cleared immediately after
+program termination. It returns 1 if it will.
+<tag/Notes/<itemize>
+<item>Some systems, maybe depending on configuration, immediately clear the screen
+after a program exits. Therefore it might be difficult to read
+the last messages printed by the program prior to its exit. This function can be used
+to decide if a delay or wait for a key press should be executed when then program
+exits.
+</itemize>
+<tag/Availability/cc65 (<tt/atari/, <tt/atarixl/, <tt/apple2/, and <tt/apple2enh/ platforms)
+<tag/Example/<verb>
+/* Hello World */
+#include <stdio.h>
+#include <unistd.h>
+#include <atari.h>
+int main(void)
+{
+    printf("Hello World\n");
+    if (doesclrscrafterexit())
+        sleep(5);
+    return 0;
+}
+</verb>
+</descrip>
+</quote>
+
+
 <sect1>em_commit<label id="em_commit"><p>
 
 <quote>

include/apple2.h

@@ -177,6 +177,9 @@ unsigned char get_ostype (void);
 void rebootafterexit (void);
 /* Reboot machine after program termination has completed. */
 
+unsigned char doesclrscrafterexit (void);
+/* Will the screen automatically be cleared after program termination. */
+
 #define ser_apple2_slot(num)  ser_ioctl (0, (void*) (num))
 /* Select a slot number from 1 to 7 prior to ser_open.
 ** The default slot number is 2.

include/atari.h

@@ -161,12 +161,13 @@ extern void __fastcall__ _scroll (signed char numlines);
                                           /* numlines < 0  scrolls down */
 
 /* misc. functions */
-extern unsigned char get_ostype(void);       /* get ROM version */
-extern unsigned char get_tv(void);           /* get TV system */
-extern void _save_vecs(void);                /* save system vectors */
-extern void _rest_vecs(void);                /* restore system vectors */
-extern char *_getdefdev(void);               /* get default floppy device */
-extern unsigned char _is_cmdline_dos(void);  /* does DOS support command lines */
+extern unsigned char get_ostype(void);            /* get ROM version */
+extern unsigned char get_tv(void);                /* get TV system */
+extern void _save_vecs(void);                     /* save system vectors */
+extern void _rest_vecs(void);                     /* restore system vectors */
+extern char *_getdefdev(void);                    /* get default floppy device */
+extern unsigned char _is_cmdline_dos(void);       /* does DOS support command lines */
+extern unsigned char doesclrscrafterexit (void);  /* will DOS clear the screen after program termination */
 
 /* global variables */
 extern unsigned char _dos_type;         /* the DOS flavour */

libsrc/atari/doesclrscr.s

@@ -0,0 +1,19 @@
+;
+; Christian Groessler, June-2016
+;
+; unsigned char doesclrscr(void);
+;
+; returns 0/1 if after program termination the screen isn't/is cleared
+;
+
+        .export  _doesclrscrafterexit
+        .import  __dos_type
+        .include "atari.inc"
+
+_doesclrscrafterexit:
+        ldx     #0
+        lda     __dos_type
+        cmp     #MAX_DOS_WITH_CMDLINE + 1
+        txa
+        rol     a
+        rts

libsrc/atari/is_cmdline_dos.s

@@ -7,14 +7,9 @@
 ;
 
         .export  __is_cmdline_dos
-        .import  __dos_type
-        .include "atari.inc"
+        .import  _doesclrscrafterexit
 
 __is_cmdline_dos:
-        ldx     #0
-        lda     __dos_type
-        cmp     #MAX_DOS_WITH_CMDLINE + 1
-        txa
-        rol     a
-        eor     #$01
+        jsr     _doesclrscrafterexit    ; currently (unless a DOS behaving differently is popping up)
+        eor     #$01                    ; we can get by with the inverse of _doesclrscrafterexit
         rts

libsrc/atari/targetutil/w2cas.c

@@ -35,7 +35,7 @@ static struct __iocb *findfreeiocb(void)
 static void exitfn(void)
 {
     /* if DOS will automatically clear the screen, after the program exits, wait for a keypress... */
-    if (! _is_cmdline_dos())
+    if (doesclrscrafterexit())
         cgetc();
 }
 

testcode/lib/atari/defdev.c

@@ -13,6 +13,6 @@ extern char _defdev[];
 int main(void)
 {
         printf("default device: %s\n", _defdev);
-        if (! _is_cmdline_dos()) cgetc();
+        if (doesclrscrafterexit()) cgetc();
         return 0;
 }

testcode/lib/atari/mem.c

@@ -41,6 +41,6 @@ int main(void)
   printf("  sp:              $%04X  (stack ptr)\n", getsp());
 
   if (allocmem) free(allocmem);
-  if (! _is_cmdline_dos()) cgetc();
+  if (doesclrscrafterexit()) cgetc();
   return(0);
 }