PB/CC: Formatted (text) System Error Messages

[Lance Edmonds]

Converts a numeric system error number (ie, from GetLastError()), into a string description.

' FormatMessage() API example by Lance C. Edmonds, April 2001
' PB/CC code.  Change PRINT to MSGBOX for PB/DLL (and delete WAITKEY$).
 
#INCLUDE "win32api.inc"
FUNCTION PBMAIN
    DIM ErrText AS ASCIIZ * 1024, Result&, ErNum&
 
    ErrNum& = %RPC_S_SERVER_UNAVAILABLE
    Result& = FormatMessage(%FORMAT_MESSAGE_FROM_SYSTEM, _
                BYVAL 0, _
                ErrNum&, _
                MAKLNG(%LANG_NEUTRAL, %SUBLANG_DEFAULT), _
                ErrText, _
                SIZEOF(ErrText), _
                BYVAL 0)
    REPLACE CHR$(13,10) WITH "" IN ErrText
    PRINT $DQ ErrText $DQ
    WAITKEY$
END FUNCTION

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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Dave Navarro]

Lance,

There is a similar sample on the PB/CC disk called WINERR.BAS. It does not use the "default language" as yours does, however. You may want to update the WINERR.BAS example for the next release of PB/CC.

------------------
Home of the BASIC Gurus
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[This message has been edited by Dave Navarro (edited April 27, 2001).]

[Tom Hanlin]

The language info needs to be pulled together by MAKELANGID, for which MAKLNG is,
unfortunately, not a replacement. While we're at it, let's lose the static buffer.

' FormatMessage() API example by Tom Hanlin, August 2001
  
#COMPILE EXE
#INCLUDE "win32api.inc"
 
FUNCTION MAKELANGID (BYVAL p AS WORD, BYVAL s AS WORD) AS DWORD

    LOCAL dResult AS DWORD

    dResult = s
    SHIFT LEFT dResult, 10
    dResult = dResult OR p

    FUNCTION = dResult

END FUNCTION
 
FUNCTION WinErrorText (BYVAL dError AS DWORD) AS STRING

    LOCAL pBuffer   AS ASCIIZ PTR
    LOCAL ncbBuffer AS DWORD

    ncbBuffer = FormatMessage( _
                    %FORMAT_MESSAGE_ALLOCATE_BUFFER _
                 OR %FORMAT_MESSAGE_FROM_SYSTEM _
                 OR %FORMAT_MESSAGE_IGNORE_INSERTS, _
                    BYVAL %NULL, _
                    dError, _
                    BYVAL MAKELANGID(%LANG_NEUTRAL, %SUBLANG_DEFAULT), _
                    BYVAL VARPTR(pBuffer), _
                    0, _
                    BYVAL %NULL)

    IF ncbBuffer THEN
        FUNCTION = PEEK$(pBuffer, ncbBuffer)
        LocalFree pBuffer
    ELSE
        FUNCTION = "Unknown error, code = &H" + HEX$(dError, 8)
    END IF

END FUNCTION
 
FUNCTION PBMAIN() AS LONG
#IF %DEF(%PBCC32)
    STDOUT WinErrorText(%ERROR_OUTOFMEMORY)
    WAITKEY$
#ELSE
    MSGBOX WinErrorText(%ERROR_OUTOFMEMORY)
#ENDIF
END FUNCTION

------------------
Tom Hanlin
PowerBASIC Staff