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Write Text at a 64-bit Offset in a Remote SFTP File

Demonstrates the Chilkat SFtp.WriteFileText64 method, which encodes text and writes it at a specific 64-bit byte offset in an open handle. The arguments are the handle, the offset, the charset, and the text. The 64-bit offset supports very large files.

Background: A 32-bit offset tops out at about 4 GB, so files larger than that require the 64-bit form to address positions beyond that boundary. The behavior is otherwise identical to the 32-bit version — the only difference is the width of the offset argument, chosen to match the size of the file you are working with.

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Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

#  Demonstrates the SFtp.WriteFileText64 method, which encodes text and writes it at a specific
#  64-bit byte offset in an open handle.  The 1st argument is the handle, the 2nd is the offset,
#  the 3rd is the charset, and the 4th is the text.  The 64-bit offset supports very large files.

$sftp = New-Object Chilkat.SFtp

#  Connect, authenticate, and initialize the SFTP subsystem.
$port = 22
$success = $sftp.Connect("sftp.example.com",$port)
if ($success -eq $false) {
    $($sftp.LastErrorText)
    exit
}

#  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 -eq $false) {
    $($sftp.LastErrorText)
    exit
}

$success = $sftp.InitializeSftp()
if ($success -eq $false) {
    $($sftp.LastErrorText)
    exit
}

$handle = $sftp.OpenFile("subdir/hugefile.dat","readWrite","openOrCreate")
if ($sftp.LastMethodSuccess -eq $false) {
    $($sftp.LastErrorText)
    exit
}

#  Write at a byte offset beyond the 32-bit (4 GB) range.
$offset = 5000000000
$success = $sftp.WriteFileText64($handle,$offset,"utf-8","MARKER")
if ($success -eq $false) {
    $($sftp.LastErrorText)
    exit
}

$success = $sftp.CloseHandle($handle)
if ($success -eq $false) {
    $($sftp.LastErrorText)
    exit
}

$("Wrote at the 64-bit offset.")

$sftp.Disconnect()