Xojo Plugin

Create a Hard Link on an SFTP Server

Demonstrates the Chilkat SFtp.HardLink method, which creates a hard link to an existing remote file. The first argument is the existing file and the second is the new link path. It uses the OpenSSH hardlink@openssh.com extension and succeeds only when the server supports it.

Background: A hard link is a second name for the same file data, not a pointer to a path: both names are equal, the data persists until the last name is removed, and there is no "original" to break. Unlike a symbolic link it cannot span filesystems and cannot target a directory. Because it depends on a non-standard OpenSSH extension, expect it to fail against servers that do not implement it.

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Dim success As Boolean
success = False

//  Demonstrates the SFtp.HardLink method, which creates a hard link to an existing remote file.
//  The 1st argument is the existing file and the 2nd is the new link path.

Dim sftp As New Chilkat.SFtp

//  Connect, authenticate, and initialize the SFTP subsystem.
Dim port As Int32
port = 22
success = sftp.Connect("sftp.example.com",port)
If (success = False) Then
    System.DebugLog(sftp.LastErrorText)
    Return
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.
Dim password As String
password = "mySshPassword"

success = sftp.AuthenticatePw("mySshLogin",password)
If (success = False) Then
    System.DebugLog(sftp.LastErrorText)
    Return
End If

success = sftp.InitializeSftp()
If (success = False) Then
    System.DebugLog(sftp.LastErrorText)
    Return
End If

//  Create a hard link.  This uses the OpenSSH hardlink@openssh.com extension and succeeds only
//  when the server supports it.
success = sftp.HardLink("subdir/data.bin","subdir/data_backup.bin")
If (success = False) Then
    System.DebugLog(sftp.LastErrorText)
    Return
End If

System.DebugLog("Hard link created.")

sftp.Disconnect