Microsoft KB Archive/250300

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Article ID: 250300

Article Last Modified on 5/10/2003



APPLIES TO

  • Microsoft FoxPro 2.0
  • Microsoft FoxPro 2.5b for MS-DOS
  • Microsoft FoxPro 2.5a
  • Microsoft FoxPro 2.5b for MS-DOS
  • Microsoft FoxPro 2.6 for MS-DOS
  • Microsoft FoxPro 2.6a Standard Edition
  • Microsoft FoxPro 2.5b
  • Microsoft FoxPro 2.5a
  • Microsoft FoxPro 2.5b
  • Microsoft FoxPro 2.6 Standard Edition
  • Microsoft FoxPro 2.6a Standard Edition
  • Microsoft Visual FoxPro 3.0 Standard Edition
  • Microsoft Visual FoxPro 3.0b Standard Edition
  • Microsoft Visual FoxPro 5.0 Standard Edition
  • Microsoft Visual FoxPro 5.0a
  • Microsoft FoxPro 2.5b for Macintosh
  • Microsoft Visual FoxPro 2.5c for Macintosh
  • Microsoft FoxPro 2.6a Professional Edition for Macintosh
  • Microsoft Visual FoxPro 3.0 for Macintosh
  • Microsoft FoxPro 2.6 for SCO/UNIX



This article was previously published under Q250300

SYMPTOMS

The FoxPro DIR command returns the century portion of the date in the Last Update column as 19xx for any table modified after 12/31/1999.

CAUSE

The date of the last update is stored in the header of the .dbf file. The DIR command looks at the table header to retrieve the last update information. Because this information is stored in YYMMDD format, FoxPro can not determine the century and assumes the 1900s.

RESOLUTION

Two possible workarounds are described in this section. The first workaround uses the ADIR function to provide basic information about the tables. This code can be modified to return information on all files and not just FoxPro tables. Copy this code into a program and execute it:

nCnt=ADIR(aFileList,"*.DBF")
FOR x = 1 TO nCnt
    ? aFileList[x,1], aFileList[x,2], aFileList[x,3]
ENDFOR

                

The second code example provides a more extensive workaround that also uses the ADIR function. Copy the code sample into a program named Zdir.prg and run it with one of the following commands:

  • DO Zdir

    -or-

  • DO Zdir with "*.DBF"

    -or-

  • =Zdir("*.DBF")

    To retrieve a list of any file type, use the following syntax:

    DO Zdir WITH "*.*"
                        



Here is the code sample:

PARAMETERS cFileMask
* Output strings
PRIVATE cFileName, cRecCount, cFileDate, cFileSize
* Environment Settings
PRIVATE cSetTalk, cSetEscape, cOnError, cSetResource

PRIVATE nFileCnt, nFileSize, cReadStr, x, hdl, nIdx, lVFP, cByte1, cTempAlias, cFileToOpen
PRIVATE nCol, nSRows, nSCols, cJustPath, lDBF, nLen, aFileList[1], nTableType, nCnt
PRIVATE lCancel

IF SET('TALK') = "ON"
    SET TALK OFF
    cSetTalk = "ON"
ELSE
    cSetTalk = "OFF"
ENDIF

cOnError = ON("ERROR")

cSetEscape = SET('ESCAPE')
SET ESCAPE OFF

cSetResource = SET('RESOURCE')
SET RESOURCE OFF

* Status of the cancel key
lCancel = .F.

* Used for scaling the rows and columns to the current desktop
nSRows = SROWS()
nSCols = SCOLS()

* Is this VFP - used in determining table type on Fox 2.x
lVFP = ( "VISUAL" $ UPPER(VERSION()) )

IF TYPE("cFileMask") <> "C"
    cFileMask = "*.dbf"
ENDIF

cJustPath = JUSTPATH(cFileMask)
* Set the path to either the path passed in or the current folder
cJustPath = ADDBS(IIF(EMPTY(cJustPath), SYS(5) + SYS(2003), cJustPath))

lDBF = ( UPPER(JUSTEXT(cFileMask)) = "DBF" )

nFileCnt = ADIR(aFileList, cFileMask)
IF nFileCnt = 0
    DIMENSION aFileList[1,5]
    nFileSize = 0
ELSE
*** NOTE -- DIR puts '_' first, ASORT puts "_" last
    =ASORT(aFileList)
ENDIF

nFileSize = 0
nCol = 0
?  && Start with a blank line
IF lDBF
    ? "Database Table/DBF files"
    ?? " # Records" AT 25
    ?? "Last Update" AT 37
    ?? "      Size" AT 50
ENDIF
IF nFileCnt = 0
    ? "None"
ENDIF

cTempAlias = SYS(2015)
FOR x = 1 TO nFileCnt
    cFileName = aFileList[x,1]
    cFileToOpen = ALLTRIM(cJustPath + cFileName)
    cFileDate = PADL(DTOC(aFileList[x,3]), 11)

    IF lDBF
        hdl = FOPEN(cFileToOpen, 0)

        IF hdl > 0
* Nobody has the table exclusive, so check the header for record count
            cByte1 = dec2hex(str2long(FREAD(hdl, 1)))  && Table type
            cReadStr = ""
            FOR nCnt = 7 TO 4 STEP -1
                nIdx = FSEEK(hdl, nCnt, 0)
                cReadStr = cReadStr + dec2hex(str2long(FREAD(hdl, 1)))
            ENDFOR
            cRecCount = PADL(STR(Hex2Dec(cReadStr)), 10)  && Convert the Hex string to numeric and then format
            =FCLOSE(hdl)

* Check to see if the table is Fox 2.x or VFP or Not a table
            DO CASE
            CASE INLIST(cByte1, "02", "03", "43", "63", "83", "8B", "CB", "F5", "FB")
* FoxPro 2.x table
                nTableType = 1
            CASE INLIST(cByte1, "30")
* Visual FoxPro Table
                nTableType = 2
            OTHERWISE
* Not a table
                nTableType = 0
            ENDCASE
            IF nTableType = 0 ;
                    OR (nTableType = 2 AND NOT lVFP)
                cFileName = cFileName + "  Not a Fox database"
                cRecCount = ""
            ENDIF
        ELSE
* File cannot be opened at all.
            cRecCount = "Can't read file"
            cFileDate = ""
        ENDIF

        cFileSize = PADL(STR(aFileList[x,2]), 11)

        ?  cFileName
        ?? cRecCount AT 25
        ?? cFileDate AT 37
        ?? cFileSize AT 50
    ELSE
* Format the output to fit columns on the desktop.
        IF nCol = 0
            ? cFileName AT nCol*14
        ELSE
            ?? cFileName AT nCol*14
        ENDIF
        nLen = INT(LEN(ALLTRIM(cFileName)) / 13)
        IF nLen > 0
            nCol = nCol + nLen
        ENDIF
        nCol = IIF((nCol + 2) * 14 > nSCols, 0, nCol + 1)
    ENDIF
    nFileSize = nFileSize + aFileList[x,2]

    IF INT(ROW()) >= INT(nSRows) - 2 ;
            AND nCol = 0
        WAIT WINDOW
        lCancel = ( LASTKEY() = 27 )  && User hit the escape key
        IF NOT lCancel
            CLEAR
        ENDIF
    ENDIF
    IF lCancel
        EXIT
    ENDIF
ENDFOR
IF lCancel
    ? "*** INTERRUPTED ***"
ELSE
    ?
    ? TRANSFORM(nFileSize, "999999999") + " bytes in " + ALLTRIM(STR(nFileCnt)) + " files."
    ? TRANSFORM(DISKSPACE(), "999999999") + " bytes remaining on drive."
ENDIF

IF cSetTalk = "ON"
    SET TALK ON
ENDIF
IF cSetEscape = "ON"
    SET ESCAPE ON
ENDIF

IF cSetResource = "ON"
    SET RESOURCE ON
ENDIF

RETURN ""

FUNCTION Hex2Dec
******************************************************************************
* passed:  1-byte integer (up to 255)
* returns:  1-byte hex string (up to FF)
* example:
*   nDecimal = 111
*   cHex = dec2hex(nDecimal)   returns "6F"
PARAMETER cHexStr
PRIVATE nDecimal
cHexStr = UPPER(cHexStr)
nDecimal = 0
FOR i=1 TO LEN(cHexStr)
    nDecimal = nDecimal + IIF(ISDIGIT(SUBSTR(cHexStr, i, 1)), ;
        VAL(SUBSTR(cHexStr, i, 1)), ;
        ASC(SUBSTR(cHexStr, i, 1)) - ASC('A') + 10) * 16 ^ (LEN(cHexStr) - i)
ENDFOR

RETURN nDecimal

FUNCTION dec2hex
******************************************************************************
* passed:  1-byte integer (up to 255)
* returns:  1-byte hex string (up to FF)
* example:
*   nDecimal = 111
*   cHex = dec2hex(nDecimal)   returns "6F"
PARAMETER nDecimal
PRIVATE cBit1, cBit2, cHexStr
cBit1 = INT(nDecimal/16)
cBit2 = nDecimal - (cBit1 * 16)

cHexStr = CHR(IIF(cBit1 > 9, 55, 48) + cBit1) + ;
    CHR(IIF(cBit2 > 9, 55, 48) + cBit2)
RETURN cHexStr

FUNCTION str2long
******************************************************************************
* passed:  4-byte character string (m.longstr) in low-high ASCII format
* returns:  long integer value
* example:
*   m.longstr = "1111"
*   m.longval = str2long(m.longstr)

PARAMETERS cLongStr
PRIVATE i, nDecimal
nDecimal = 0
FOR i = 0 TO 24 STEP 8
    nDecimal = nDecimal + (ASC(cLongStr) * (2^i))
    cLongStr = RIGHT(cLongStr, LEN(cLongStr) - 1)
NEXT
RETURN nDecimal

FUNCTION JUSTPATH
* Returns just the pathname.
PARAMETERS m.FilName
m.FilName = ALLTRIM(UPPER(m.FilName))
IF "\" $ m.FilName
    m.FilName = SUBSTR(m.FilName,1,RAT("\",m.FilName))
    IF RIGHT(m.FilName,1) = "\" AND LEN(m.FilName) > 1 ;
            AND SUBSTR(m.FilName,LEN(m.FilName)-1,1) <> ":"
        FilName = SUBSTR(m.FilName,1,LEN(m.FilName)-1)
    ENDIF
    RETURN m.FilName
ELSE
    RETURN ""
ENDIF

FUNCTION JUSTEXT
* Return just the extension from "filname"
PARAMETERS m.FilName
PRIVATE m.ext
m.FilName = JUSTFNAME(m.FilName)   && prevents problems with ..\ paths
m.ext = ""
IF AT(".", m.FilName) > 0
    m.ext = SUBSTR(m.FilName, AT(".", m.FilName) + 1, 3)
ENDIF
RETURN UPPER(m.ext)

FUNCTION JUSTFNAME
* Return just the filename (i.e., no path) from "filname"
PARAMETERS m.FilName
IF RAT("\",m.FilName) > 0
    m.FilName = SUBSTR(m.FilName,RAT("\",m.FilName)+1,255)
ENDIF
IF AT(":",m.FilName) > 0
    m.FilName = SUBSTR(m.FilName,AT(":",m.FilName)+1,255)
ENDIF
RETURN ALLTRIM(UPPER(m.FilName))

FUNCTION ADDBS
* Add a backslash unless there is one already there.
PARAMETER m.pathname
PRIVATE m.separator
m.separator = IIF(_MAC,":","\")
m.pathname = ALLTRIM(UPPER(m.pathname))
IF !(RIGHT(m.pathname,1) $ '\:') AND !EMPTY(m.pathname)
    m.pathname = m.pathname + m.separator
ENDIF
RETURN m.pathname
                

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

Steps to Reproduce the Behavior

  1. Change the system date of the computer to 02/01/2000. The specific date is not critical as long as the year is 2000 or later.
  2. In the FoxPro Command window, type the following without the comments:

    SET CENTURY ON
    USE <tablename>         && Name of the table.
    APPEND BLANK            && Appends a blank record to the table.DIR
    USE                     && This closes the table.
    DIR
                        

    An incorrect answer is listed for the modified table: 02/01/1900.

NOTE: Remember to reset the system date of your computer back to today.

REFERENCES

For additional information about the LUPDATE(), the FDATE(), and the ADIR() functions, click the article numbers below to view the articles in the Microsoft Knowledge Base:

176481 FIX: LUPDATE() Does Not Report Correct Century for Year 2000


130165 PRB: LUPDATE() Does Not Return Date of Last Update


113943 INFO: New and Enhanced Commands and Functions in FoxPro Ver 2.6


100554 INFO: Using ADIR() Function to Obtain MS-DOS File Information


Microsoft FoxPro Help, topic: "LUPDATE() Function"

Microsoft FoxPro Help, topic: "FDATE() Function"

Microsoft FoxPro Help, topic: "ADIR() Function"


Additional query words: Y2K DIR

Keywords: kbxbase kbcodesnippet kbprb kbpending KB250300