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DataFlex

Send an SSH IGNORE Message over SFTP

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Demonstrates the Chilkat SFtp.SendIgnore method, which sends an SSH IGNORE message. It takes no arguments. The server sends no reply, but a successful send helps confirm the connection is still writable. No SFTP file handle is required.

Background: The SSH IGNORE message is discarded by the peer by design; its value is as a lightweight keep-alive or liveness probe. During a long-idle SFTP session — for instance while waiting between scheduled transfers — a periodic SendIgnore both keeps the connection from being dropped for inactivity and proves the link is still usable, without touching any file.

Chilkat DataFlex Downloads

DataFlex
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoSftp
    Integer iPort
    String sPassword
    String sTemp1

    Move False To iSuccess

    //  Demonstrates the SFtp.SendIgnore method, which sends an SSH IGNORE message.  It takes no
    //  arguments.  The server sends no reply, but a successful send helps confirm the connection is
    //  still writable.  No SFTP file handle is required.

    Get Create (RefClass(cComChilkatSFtp)) To hoSftp
    If (Not(IsComObjectCreated(hoSftp))) Begin
        Send CreateComObject of hoSftp
    End

    //  Step 1: Connect the SSH transport.  Port 22 is the usual port.
    Move 22 To iPort
    Get ComConnect Of hoSftp "sftp.example.com" iPort To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoSftp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  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.
    Move "mySshPassword" To sPassword

    Get ComAuthenticatePw Of hoSftp "mySshLogin" sPassword To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoSftp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  Step 3: Open the SFTP subsystem.  This must be done after authentication and before any
    //  file or directory operations.
    Get ComInitializeSftp Of hoSftp To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoSftp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  Send an IGNORE message to verify the connection is still writable.
    Get ComSendIgnore Of hoSftp To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoSftp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln "IGNORE message sent."

    Send ComDisconnect To hoSftp


End_Procedure