Receive from an SSH Channel Until Any Pattern Matches

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Demonstrates the Chilkat Ssh.ChannelReceiveUntilMatchN method, which works like ChannelReceiveUntilMatch but returns when any pattern in a StringArray matches. The arguments are the channel number, the pattern array, the charset, and case sensitivity. The array must contain at least one element.

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.

Dim success As Long
success = 0

'  Demonstrates the Ssh.ChannelReceiveUntilMatchN method, which receives text until ANY pattern
'  in a StringArray is matched.  The 1st argument is the channel number, the 2nd is the array of
'  patterns, the 3rd is the charset, and the 4th selects case-sensitive matching.

Dim ssh As New ChilkatSsh

Dim sshPort As Long
sshPort = 22
success = ssh.Connect("ssh.example.com",sshPort)
If (success = 0) Then
    Debug.Print ssh.LastErrorText
    Exit Sub
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 = ssh.AuthenticatePw("mySshLogin",password)
If (success = 0) Then
    Debug.Print ssh.LastErrorText
    Exit Sub
End If

Dim channelNum As Long
channelNum = ssh.OpenSessionChannel()
If (channelNum < 0) Then
    Debug.Print ssh.LastErrorText
    Exit Sub
End If

'  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.
success = ssh.SendReqShell(channelNum)
If (success = 0) Then
    Debug.Print ssh.LastErrorText
    Exit Sub
End If

'  There is no prompt to match on.  Instead, run a command that prints one marker on success
'  and a different marker on failure, then wait for whichever appears first.
success = ssh.ChannelSendString(channelNum,"test -f /etc/hosts && echo OK_MARKER || echo ERR_MARKER" & vbLf,"utf-8")
If (success = 0) Then
    Debug.Print ssh.LastErrorText
    Exit Sub
End If

Dim patterns As New CkStringArray
success = patterns.Append("OK_MARKER")
success = patterns.Append("ERR_MARKER")

'  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.
ssh.ReadTimeoutMs = 15000

Dim caseSensitive As Long
caseSensitive = 0
success = ssh.ChannelReceiveUntilMatchN(channelNum,patterns,"utf-8",caseSensitive)
If (success = 0) Then
    Debug.Print ssh.LastErrorText
    Exit Sub
End If

Dim output As String
output = ssh.GetReceivedText(channelNum,"utf-8")
If (ssh.LastMethodSuccess = 0) Then
    Debug.Print ssh.LastErrorText
    Exit Sub
End If

Debug.Print output

ssh.Disconnect