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Receive from an SSH Channel Until a Pattern Matches

Demonstrates the Chilkat Ssh.ChannelReceiveUntilMatch method, which receives text until the accumulated text matches a pattern. The arguments are the channel number, the pattern, the charset, and whether matching is case-sensitive. Existing buffered text is checked before waiting for more network data.

Important: Set the ReadTimeoutMs property before calling this method. It defaults to 0, meaning no limit, so without it the call waits forever if the received data never contains a match.

Background: Driving a shell channel means knowing when the remote side has finished talking. With no PTY requested the shell is non-interactive and never prints a prompt, so the reliable signal is a marker you deliberately echo after your command. This method automates "read until you see X." The pattern syntax is deliberately minimal: literal characters plus *, which matches zero or more characters and can span line breaks. ? and bracket classes are not supported, and backslash does not escape a literal *.

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Local $bSuccess = False

;  Demonstrates the Ssh.ChannelReceiveUntilMatch method, which receives text until the
;  accumulated text matches a pattern.  The 1st argument is the channel number, the 2nd is the
;  pattern, the 3rd is the charset, and the 4th selects case-sensitive matching.  The pattern
;  supports literal characters plus "*", which matches zero or more characters.

$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

;  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

;  There is no prompt to wait for, so make the command itself announce when it has finished
;  by echoing a marker after it.
$bSuccess = $oSsh.ChannelSendString($iChannelNum,"ls -l /tmp; echo DONE_MARKER" & @LF,"utf-8")
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

;  Receive until the marker appears in the output.
Local $bCaseSensitive = False
$bSuccess = $oSsh.ChannelReceiveUntilMatch($iChannelNum,"DONE_MARKER","utf-8",$bCaseSensitive)
If ($bSuccess = False) Then
    ConsoleWrite($oSsh.LastErrorText & @CRLF)
    Exit
EndIf

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

ConsoleWrite($sOutput & @CRLF)

$oSsh.Disconnect