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SSH Remote Shell with Multiple Commands

Demonstrates running several commands one after another in a single remote shell session, retrieving each command's output separately. No PTY is requested, so each command is followed by an echoed marker that signals where its output ends.

Background: Interleaving commands and reads in one shell requires a way to know where each command's output stops. An interactive session would use the shell prompt, but without a PTY the shell is non-interactive and never prints one — so the dependable technique is to append echo SOME_MARKER to each command and read up to that marker. Retrieving the text also clears the receive buffer, which matters here: if a marker were left buffered, the next receive would match it immediately and return the wrong output.

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Local $bSuccess = False

;  This example requires the Chilkat API to have been previously unlocked.
;  See Global Unlock Sample for sample code.

;  Demonstrates running several commands one after another in a single remote shell session,
;  retrieving each command's output separately.
;  
;  No PTY is requested, so the shell runs non-interactively and never prints a command prompt.
;  Because there is no prompt to synchronize on, each command is followed by an "echo" of a
;  unique marker, and the output is read up to that marker.

$oSsh = ObjCreate("Chilkat.Ssh")

Local $sHostname = "ssh.example.com"
Local $iPort = 22
$bSuccess = $oSsh.Connect($sHostname,$iPort)
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

;  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.
Local $sPassword = "mySshPassword"

$bSuccess = $oSsh.AuthenticatePw("mySshLogin",$sPassword)
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

Local $iChannelNum = $oSsh.OpenSessionChannel()
If ($iChannelNum < 0) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

;  Start a shell WITHOUT requesting a PTY.  Without a PTY the shell sees it is connected to a
;  raw data pipe and enters non-interactive mode: it suppresses the command prompt, does not
;  echo typed commands back, and skips interactive login scripts.  The output is therefore
;  clean and easily parseable -- but because no prompt is ever sent, code must not wait for
;  one.  Instead, have each command print a predictable marker, or wait for EOF / channel close.
$bSuccess = $oSsh.SendReqShell($iChannelNum)
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

;  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
;  which means no limit -- without it, this call waits forever if the received data never
;  contains a match.
$oSsh.ReadTimeoutMs = 15000

Local $bCaseSensitive = True

;  ---- 1st command: change directory ----
$bSuccess = $oSsh.ChannelSendString($iChannelNum,"cd /tmp; echo END_OF_CMD_1" & @LF,"utf-8")
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

$bSuccess = $oSsh.ChannelReceiveUntilMatch($iChannelNum,"END_OF_CMD_1","utf-8",$bCaseSensitive)
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

;  Retrieving the text also clears the receive buffer, which matters: if the next marker were
;  left in the buffer, the following receive would match immediately.
Local $sCmdOutput = $oSsh.GetReceivedText($iChannelNum,"utf-8")
If ($oSsh.LastMethodSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite($sCmdOutput & @CRLF)

;  ---- 2nd command: directory listing ----
$bSuccess = $oSsh.ChannelSendString($iChannelNum,"ls; echo END_OF_CMD_2" & @LF,"utf-8")
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

$bSuccess = $oSsh.ChannelReceiveUntilMatch($iChannelNum,"END_OF_CMD_2","utf-8",$bCaseSensitive)
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

$sCmdOutput = $oSsh.GetReceivedText($iChannelNum,"utf-8")
If ($oSsh.LastMethodSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite($sCmdOutput & @CRLF)

;  ---- 3rd command: long listing, then finish the session ----
$bSuccess = $oSsh.ChannelSendString($iChannelNum,"ls -l" & @LF,"utf-8")
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

;  No more input will be sent.
$bSuccess = $oSsh.ChannelSendEof($iChannelNum)
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

$bSuccess = $oSsh.ChannelReceiveToClose($iChannelNum)
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

$sCmdOutput = $oSsh.GetReceivedText($iChannelNum,"utf-8")
If ($oSsh.LastMethodSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite($sCmdOutput & @CRLF)

$oSsh.Disconnect