Mailing List Archive: Re: sizeof(structure)

[REBOL] Re: sizeof(structure)

From: greggirwin:mindspring at: 18-Sep-2003 22:48


Hi Paul,

PT> Yeah I actually tried that thinking the same but had no luck with it.  I get
PT> a return value of 0 which denotes failure of the GetVersionEx function.

The fixed char array will give you grief, if you haven't already dealt
with them in structs. Here's a very quick hack for you, with credit to
Pekr and Cyphre for the nifty trick of generating elements dynamically
to emulate char arrays in structs.

-- Gregg

make-elements: func [name count type /local result][
    if not word? type [type: type?/word type]
    result: copy "^/"
    repeat i count [
        append result join name [i " [" type "]" newline]
    ]
    to block! result
]

kernel.dll: load/library %kernel32.dll

OSVERSIONINFOEXA: make struct! OSVERSIONINFOEXA-def: compose/deep [
    dwOSVersionInfoSize     [integer!]      ; DWORD
    dwMajorVersion      [integer!]      ; DWORD
    dwMinorVersion      [integer!]      ; DWORD
    dwBuildNumber       [integer!]      ; DWORD
    dwPlatformId        [integer!]      ; DWORD
    (make-elements 'szCSDVersion 128 #"@")  ; TCHAR
] none
OSVERSIONINFOEXA/dwOSVersionInfoSize: length? third OSVERSIONINFOEXA

GetVersionEx: make routine! compose/deep/only [
    lpVersionInformation    [struct! (OSVERSIONINFOEXA-def)] ;LPOSVERSIONINFO
    return:     [integer!]  ;BOOL
] kernel.dll "GetVersionExA"

get-version: has [res] [
    res: GetVersionEx OSVERSIONINFOEXA
    either 0 = res [none][OSVERSIONINFOEXA]
]

res: get-version
print [
    "Major:" res/dwMajorVersion newline
    "Minor:" res/dwMinorVersion newline
    "Build:" res/dwBuildNumber  newline
    "Version:" to-string copy/part at third OSVERSIONINFOEXA 21 128
]

free kernel.dll