Get Windows version

Author: sunjammer (talk, contrib)

Description

A simple function to return the version of Windows that the script is running on. It can detect Windows 95 through Windows 7, returns the version number if it is Windows NT 3 or 4 and returns a blank string if it can not determine the Windows version.

The Script

; GetWindowsVersion 2.0 (2008-01-07)
;
; Based on Yazno's function, http://yazno.tripod.com/powerpimpit/
; Update by Joost Verburg
; Update (Macro, Define, Windows 7 detection) - John T. Haller of PortableApps.com - 2008-01-07
;
; Usage: ${GetWindowsVersion} $R0
;
; $R0 contains: 95, 98, ME, NT x.x, 2000, XP, 2003, Vista, 7 or '' (for unknown)
 
Function GetWindowsVersion
 
  Push $R0
  Push $R1
 
  ClearErrors
 
  ReadRegStr $R0 HKLM \
  "SOFTWARE\Microsoft\Windows NT\CurrentVersion" CurrentVersion
 
  IfErrors 0 lbl_winnt
 
  ; we are not NT
  ReadRegStr $R0 HKLM \
  "SOFTWARE\Microsoft\Windows\CurrentVersion" VersionNumber
 
  StrCpy $R1 $R0 1
  StrCmp $R1 '4' 0 lbl_error
 
  StrCpy $R1 $R0 3
 
  StrCmp $R1 '4.0' lbl_win32_95
  StrCmp $R1 '4.9' lbl_win32_ME lbl_win32_98
 
  lbl_win32_95:
    StrCpy $R0 '95'
  Goto lbl_done
 
  lbl_win32_98:
    StrCpy $R0 '98'
  Goto lbl_done
 
  lbl_win32_ME:
    StrCpy $R0 'ME'
  Goto lbl_done
 
  lbl_winnt:
 
  StrCpy $R1 $R0 1
 
  StrCmp $R1 '3' lbl_winnt_x
  StrCmp $R1 '4' lbl_winnt_x
 
  StrCpy $R1 $R0 3
 
  StrCmp $R1 '5.0' lbl_winnt_2000
  StrCmp $R1 '5.1' lbl_winnt_XP
  StrCmp $R1 '5.2' lbl_winnt_2003
  StrCmp $R1 '6.0' lbl_winnt_vista
  StrCmp $R1 '6.1' lbl_winnt_7 lbl_error
 
  lbl_winnt_x:
    StrCpy $R0 "NT $R0" 6
  Goto lbl_done
 
  lbl_winnt_2000:
    Strcpy $R0 '2000'
  Goto lbl_done
 
  lbl_winnt_XP:
    Strcpy $R0 'XP'
  Goto lbl_done
 
  lbl_winnt_2003:
    Strcpy $R0 '2003'
  Goto lbl_done
 
  lbl_winnt_vista:
    Strcpy $R0 'Vista'
  Goto lbl_done
 
  lbl_winnt_7
    Strcpy $R0 '7'
  Goto lbl_done
 
  lbl_error:
    Strcpy $R0 ''
  lbl_done:
 
  Pop $R1
  Exch $R0
 
FunctionEnd
 
!macro GetWindowsVersion OUTPUT_VALUE
	Call GetWindowsVersion
	Pop `${OUTPUT_VALUE}`
!macroend
 
!define GetWindowsVersion '!insertmacro "GetWindowsVersion"'