-- card: 37379 from stack: in.5
-- bmap block id: 36823
-- flags: 0000
-- background id: 3858
-- name: MonitorCount
----- HyperTalk script -----
on HideObjects
  hide cd btn "Try It!"
end HideObjects

on ShowObjects
  show cd btn "Try It!"
end ShowObjects


-- part 1 (button)
-- low flags: 00
-- high flags: A002
-- rect: left=82 top=185 right=219 bottom=175
-- title width / last selected line: 0
-- icon id / first selected line: 0 / 0
-- text alignment: 1
-- font id: 0
-- text size: 12
-- style flags: 8192
-- line height: 16
-- part name: Try it!
----- HyperTalk script -----
on mouseUp
  answer "This Mac has" && MonitorCount() && "monitors."
end mouseUp




-- part contents for background part 38
----- text -----
30/50

-- part contents for background part 20
----- text -----
    This XFCN returns the number of active (useable) monitors attached to the Mac.

     Calling syntax : MonitorCount()

     Returns: the number of monitors.


-- part contents for background part 42
----- text -----
unit monitorCount;
{}
{monitorCount()}
{ Check and report the number of monitors currenty attached. }
{}
{}
{   brought to you by:      Anup Murarka             Eric Carlson         }
{                       ALINK:  SKEPTIC           ALINK:  cyNic   }
{                                   CIS:  76004,3356         }
{}
{               We are part of the Support Tools Development Group,     }
{               Apple Computer, Inc.      }
{}
{               please DO NOT contack Mac DTS for support of this code!    }
{}
{               please DO contact the authors for support of this code!     }
{}
{               Send comments, bug reports, requests to any of the above   }
{               E-mail addresses or to:}
{}
{                           (one of us)                  }
{                           Apple Computer, Inc.          }
{                           900 E. Hamilton, Ave.          }
{                           Campbell, CA   95008      }
{                           M/S 72-L                     }
{}
{   Copyright:   © 1989, 1990 by Apple Computer, Inc., all rights reserved.     }
{}
{ written by Eric Carlson                                        }
{ AppleLink:  cyNic                                              }
{ modification history                                                                                        }
{          Date                  Initials                                    Comments                                   }
{          ----              ------          --------------------------------------------------}
{       9/1/89             ec            first written                                                               }
{       6/6/90             ec            cleaned code, added comments                                         }
{}
interface
 uses
  HyperXCMD;

 procedure main (paramPtr: XCmdPtr);

implementation


 function askedForHelp (paramPtr: XCmdPtr;
       syntaxMsg: Str255;
       copyRightMsg: Str255): boolean;
{}
{   check to see if the user sent a '?' or a '!' as }
{ the only parameter. if so we will respond with }
{ the calling syntax or the copyright/version info }
{ for this external }
{}
  var
   firstStr: str255;
 begin
  askedForHelp := false;
  if paramPtr^.paramCount = 1 then
   begin
    ZeroToPas(paramPtr, paramPtr^.params[1]^, firstStr);
                    { what is the first param? }
    if firstStr = '?' then
     begin
      paramPtr^.returnValue := PasToZero(paramPtr, syntaxMsg);
      askedForHelp := true
     end     { asked for help }
    else if firstStr = '!' then
     begin
      paramPtr^.returnValue := PasToZero(paramPtr, copyRightMsg);
      askedForHelp := true
     end;    { asked for copyright info }
   end;  { one parameter passed }
 end;    { function }

 function NumberToString (paramPtr: XCmdPtr;
       num: LONGINT): Str255;
{ use the toolbox call rather than HC's }
  var
   tempStr: str255;
 begin
  NumToString(num, tempStr);
  NumberToString := tempStr;
 end;

 procedure monitorCount (paramPtr: XCmdPtr);
  const
   UTableBase = $11C;
   screenActive = 15;               { 1 if in use }

  var
   currGDevice: GDHandle;
   theSysEnv: SysEnvRec;
   envErr: OSErr;
   monitorNum: integer;
   copyRtStr, syntaxStr: str255;

  function TestDeviceAttribute (gdh: GDHandle;
       attribute: INTEGER): BOOLEAN;
  inline
   $AA2C;
  function GetDeviceList: GDHandle;
  inline
   $AA29;
  function GetGDevice: GDHandle;
  inline
   $AA32;

 begin
  syntaxStr := 'monitorCount()';
  copyRtStr := '© 1989,1990 Apple Computer, Inc. v.1.0,  by Eric Carlson.';
  if askedForHelp(paramPtr, syntaxStr, copyRtStr) then
   exit(monitorCount);                         { just asking for help }

  monitorNum := 1;                                      { assume that we'll fond just one monitor }
  envErr := SysEnvirons(1, theSysEnv);           { call sysEnvirons to see about color QD }
  if envErr = noErr then
   if theSysEnv.hasColorQD then         { only proceed if we have color QD }
    begin
     monitorNum := 0;
     currGDevice := GetDeviceList;                   { grab the first gDevice in the list }
     while (currGDevice <> nil) do                     { and step through the whole list }
      begin
       if TestDeviceAttribute(currGDevice, screenActive) then       { see if the screen is active }
        monitorNum := monitorNum + 1;                 { another gDevice = another monitor }
       currGDevice := currGDevice^^.gdNextGD;   { get the next one }
      end;
    end;

  paramPtr^.returnValue := PasToZero(paramPtr, NumberToString(paramPtr, monitorNum));
 end;

 procedure main (paramPtr: XCmdPtr);
 begin
  monitorCount(paramPtr);
 end;
end.