Is my input file too big for VB?

[rodders]

I have a very big fixed length file to read into VB6 (record length 2201).
Each record is only terminated by a line feed and not cr/lf so line input does not work.
In binary mode it works until I reach byte 2,147,483,648 which I believe is the maximum length of a variable length string variable - and then I get "Error code 63: bad record number".
What other options are available to me to access this data? help!

[CVMichael]

With files over 2GBytes, you have to switch to API

[rodders]

Thanks for the reply.
Excuse my ignorance but can anyone point me in the direction of what APIs I should be using?

[CVMichael]

These are the APIs I use:

Private Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, lpSecurityAttributes As SECURITY_ATTRIBUTES, ByVal dwCreationDisposition As Long, ByVal dwFlagsAndAttributes As Long, ByVal hTemplateFile As Long) As Long
 
Private Type OVERLAPPED
    Internal As Long
    InternalHigh As Long
    Offset As Long
    OffsetHigh As Long
    hEvent As Long
End Type
 
Private Declare Function WriteFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToWrite As Long, lpNumberOfBytesWritten As Long, lpOverlapped As Any) As Long
Private Declare Function WriteFileEx Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToWrite As Long, lpOverlapped As OVERLAPPED, ByVal lpCompletionRoutine As Long) As Long
Private Declare Function ReadFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, lpOverlapped As Any) As Long
Private Declare Function ReadFileEx Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToRead As Long, lpOverlapped As OVERLAPPED, ByVal lpCompletionRoutine As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
 
' SetFilePointer, sets AND reads pointer position
Private Declare Function SetFilePointer Lib "kernel32" (ByVal hFile As Long, ByVal lDistanceToMove As Long, lpDistanceToMoveHigh As Long, ByVal dwMoveMethod As Long) As Long

To figure out how to use them, post a question in the API forum

[rodders]

Okay, I will start a thread entitled 'Reading files > 2GB in VB using API' on the API forum.

[szlamany]

Have you tried using the FILESYSTEMOBJECT to read the file?

We have had good luck with that when recordlengths get too large for VB.

[rodders]

FileSystemObject works!

Although the MSDN help is patchy to say the least.

It was only because I read another post that I knew to include Microsoft Scripting Runtime as a reference, and the sample code for OpenTextFile has a bug in it (ForAppending=8 not 3).

I am using On Error to detect the end of file at present - but is there a 'proper' way similar to the EOF function when usin the Open statement? Again, the help is patchy on this.

[Hack]

FileSystemObject works!

Although the MSDN help is patchy to say the least.

It was only because I read another post that I knew to include Microsoft Scripting Runtime as a reference, and the sample code for OpenTextFile has a bug in it (ForAppending=8 not 3).

I am using On Error to detect the end of file at present - but is there a 'proper' way similar to the EOF function when usin the Open statement? Again, the help is patchy on this.

You could try using LOF (Length of file)

[szlamany]

We use FSO/TSO like this...

    Set tso = fso.OpenTextFile(gstrInput)
      
    Do While Not tso.AtEndOfStream
        s1 = tso.ReadLine
.
.
.
        lngReadCnt = lngReadCnt + 1
    Loop