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Wait for a Message on Any SSH Channel

Demonstrates the Chilkat Ssh.WaitForChannelMessage method, which waits for the next SSH channel message on any channel. The only argument is the poll timeout: 0 for a nonblocking check, a positive value to wait that long, or a negative value to wait with no method-level timeout. It returns the channel number the message belongs to, -1 if nothing arrived before the timeout, or -2 on another error such as a lost connection.

Background: When several channels are active at once, waiting on one specific channel would block while others sit ready. This method is the multiplexed alternative — it returns as soon as any channel has activity and tells you which one, so a single loop can service them all. The explicit timeout argument governs the wait; shorter ReadTimeoutMs values do not cut it short.

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Local $bSuccess = False

;  Demonstrates the Ssh.WaitForChannelMessage method, which waits for the next SSH channel
;  message on ANY channel.  The only argument is the poll timeout in milliseconds: 0 for a
;  nonblocking check, a positive value to wait that long, or a negative value to wait with no
;  method-level timeout.

$oSsh = ObjCreate("Chilkat.Ssh")

Local $iSshPort = 22
$bSuccess = $oSsh.Connect("ssh.example.com",$iSshPort)
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

$bSuccess = $oSsh.SendReqExec($iChannelNum,"ls -l /tmp")
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

;  Wait up to 5 seconds for the next channel message.  The return value is the channel number
;  the message belongs to, -1 if nothing arrived before the timeout, or -2 on another error.
Local $iPollTimeoutMs = 5000
Local $iResult = $oSsh.WaitForChannelMessage($iPollTimeoutMs)

If ($iResult = -2) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

If ($iResult = -1) Then
    ConsoleWrite("No channel message arrived before the timeout." & @CRLF)
EndIf

If ($iResult >= 0) Then
    ConsoleWrite("Processed a message for channel " & $iResult & @CRLF)
EndIf

$oSsh.Disconnect