VBScript

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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VBScript

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

success = 0

'  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.

set ssh = CreateObject("Chilkat.Ssh")

hostname = "ssh.example.com"
port = 22
success = ssh.Connect(hostname,port)
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
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.
password = "mySshPassword"

success = ssh.AuthenticatePw("mySshLogin",password)
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

channelNum = ssh.OpenSessionChannel()
If (channelNum < 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
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
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

'  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

caseSensitive = 1

'  ---- 1st command: change directory ----
success = ssh.ChannelSendString(channelNum,"cd /tmp; echo END_OF_CMD_1" & vbLf,"utf-8")
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

success = ssh.ChannelReceiveUntilMatch(channelNum,"END_OF_CMD_1","utf-8",caseSensitive)
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

'  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.
cmdOutput = ssh.GetReceivedText(channelNum,"utf-8")
If (ssh.LastMethodSuccess = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine(cmdOutput)

'  ---- 2nd command: directory listing ----
success = ssh.ChannelSendString(channelNum,"ls; echo END_OF_CMD_2" & vbLf,"utf-8")
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

success = ssh.ChannelReceiveUntilMatch(channelNum,"END_OF_CMD_2","utf-8",caseSensitive)
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

cmdOutput = ssh.GetReceivedText(channelNum,"utf-8")
If (ssh.LastMethodSuccess = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine(cmdOutput)

'  ---- 3rd command: long listing, then finish the session ----
success = ssh.ChannelSendString(channelNum,"ls -l" & vbLf,"utf-8")
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

'  No more input will be sent.
success = ssh.ChannelSendEof(channelNum)
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

success = ssh.ChannelReceiveToClose(channelNum)
If (success = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

cmdOutput = ssh.GetReceivedText(channelNum,"utf-8")
If (ssh.LastMethodSuccess = 0) Then
    outFile.WriteLine(ssh.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine(cmdOutput)

ssh.Disconnect 

outFile.Close