VBScript

Read Text at a String Offset from a Remote SFTP File

Demonstrates the Chilkat SFtp.ReadFileText64s method, which is like ReadFileText64 but takes the byte offset as a decimal string. The arguments are the handle, the offset string, the maximum number of bytes, and the charset.

Background: The string-offset read exists for the same reason as its write counterpart: it lets code in languages without convenient 64-bit integers still address positions in very large files by supplying the offset as text. Functionally it is identical to the int64 version.

Chilkat VBScript Downloads

Download Chilkat for VBScript

VBScript

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

success = 0

'  Demonstrates the SFtp.ReadFileText64s method, which is like ReadFileText64 but takes the byte
'  offset as a decimal string.  The 1st argument is the handle, the 2nd is the offset string, the
'  3rd is the maximum number of bytes, and the 4th is the charset.

set sftp = CreateObject("Chilkat.SFtp")

'  Connect, authenticate, and initialize the SFTP subsystem.
port = 22
success = sftp.Connect("sftp.example.com",port)
If (success = 0) Then
    outFile.WriteLine(sftp.LastErrorText)
    WScript.Quit
End If

'  Normally you would not hard-code the password in source.  You should instead obtain it
'  from an interactive prompt, environment variable, or a secrets vault.
password = "mySshPassword"

success = sftp.AuthenticatePw("mySshLogin",password)
If (success = 0) Then
    outFile.WriteLine(sftp.LastErrorText)
    WScript.Quit
End If

success = sftp.InitializeSftp()
If (success = 0) Then
    outFile.WriteLine(sftp.LastErrorText)
    WScript.Quit
End If

handle = sftp.OpenFile("subdir/hugefile.dat","readOnly","openExisting")
If (sftp.LastMethodSuccess = 0) Then
    outFile.WriteLine(sftp.LastErrorText)
    WScript.Quit
End If

'  Supplying the offset as a string is convenient in languages without a native 64-bit integer.
offset = "5000000000"
numBytes = 6
text = sftp.ReadFileText64s(handle,offset,numBytes,"utf-8")
If (sftp.LastMethodSuccess = 0) Then
    outFile.WriteLine(sftp.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine(text)

success = sftp.CloseHandle(handle)
If (success = 0) Then
    outFile.WriteLine(sftp.LastErrorText)
    WScript.Quit
End If

sftp.Disconnect 

outFile.Close