(Xojo Plugin) SSH Remote Shell Multiple Commands

Demonstrates how to start a shell on a remote SSH server, run a command, and retrieve the output, then run the next command, retrieve the output, etc.

Chilkat Xojo Plugin Download Xojo Plugin for Windows, Linux, Mac OS X, and ARM, ARM64

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

Dim ssh As New Chilkat.Ssh

// This is the prompt we'll be expecting to find in
// the output of the remote shell.
Dim myPrompt As String
myPrompt = "chilkat@ubuntu:~/workspace$"

Dim cmdOutput As String

// Connect to an SSH server:
Dim hostname As String
Dim port As Int32

// Hostname may be an IP address or hostname:
hostname = "www.some-ssh-server.com"
port = 22

Dim success As Boolean
success = ssh.Connect(hostname,port)
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Wait a max of 10 seconds when reading responses..
ssh.IdleTimeoutMs = 10000

// Authenticate using login/password:
success = ssh.AuthenticatePw("myLogin","myPassword")
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Open a session channel.  (It is possible to have multiple
// session channels open simultaneously.)
Dim channelNum As Int32
channelNum = ssh.OpenSessionChannel()
If (channelNum < 0) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

Dim termType As String
termType = "dumb"
Dim widthInChars As Int32
widthInChars = 120
Dim heightInChars As Int32
heightInChars = 40
// Use 0 for pixWidth and pixHeight when the dimensions
// are set in number-of-chars.
Dim pixWidth As Int32
pixWidth = 0
Dim pixHeight As Int32
pixHeight = 0
success = ssh.SendReqPty(channelNum,termType,widthInChars,heightInChars,pixWidth,pixHeight)
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Start a shell on the channel:
success = ssh.SendReqShell(channelNum)
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

//  Run the 1st command in the remote shell, which will be to
//  "cd" to a subdirectory.
success = ssh.ChannelSendString(channelNum,"cd workspace" + EndOfLine.Windows,"ansi")
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Retrieve the output.
success = ssh.ChannelReceiveUntilMatch(channelNum,myPrompt,"ansi",True)
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

//  Display what we've received so far.  This clears
//  the internal receive buffer, which is important.
//  After we send the command, we'll be reading until
//  the next command prompt.  If the command prompt
//  is already in the internal receive buffer, it'll think it's
//  already finished...
cmdOutput = ssh.GetReceivedText(channelNum,"ansi")
If (ssh.LastMethodSuccess <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

System.DebugLog(cmdOutput)

//  Run the 2nd command in the remote shell, which will be
//  to "ls" the directory.
success = ssh.ChannelSendString(channelNum,"ls" + EndOfLine.Windows,"ansi")
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Retrieve and display the output.
success = ssh.ChannelReceiveUntilMatch(channelNum,myPrompt,"ansi",True)
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

cmdOutput = ssh.GetReceivedText(channelNum,"ansi")
If (ssh.LastMethodSuccess <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

System.DebugLog(cmdOutput)

//  Start the final command in the remote shell.  This example
//  will send a "ls -l" command to retrieve the long format directory listing.
success = ssh.ChannelSendString(channelNum,"ls -l" + EndOfLine.Windows,"ansi")
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Send an EOF.  This tells the server that no more data will 
// be sent on this channel.  The channel remains open, and
// the SSH client may still receive output on this channel.
success = ssh.ChannelSendEof(channelNum)
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Read whatever output may already be available on the
// SSH connection.  ChannelReadAndPoll returns the number of bytes
// that are available in the channel's internal buffer that
// are ready to be "picked up" by calling GetReceivedText
// or GetReceivedData.
// A return value of -1 indicates failure.
// A return value of -2 indicates a failure via timeout.

// The ChannelReadAndPoll method waits
// for data to arrive on the connection usingi the IdleTimeoutMs
// property setting.  Once the first data arrives, it continues
// reading but instead uses the pollTimeoutMs passed in the 2nd argument:
// A return value of -2 indicates a timeout where no data is received.
Dim n As Int32
Dim pollTimeoutMs As Int32
pollTimeoutMs = 2000
n = ssh.ChannelReadAndPoll(channelNum,pollTimeoutMs)
If (n < 0) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Close the channel:
success = ssh.ChannelSendClose(channelNum)
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

// Perhaps we did not receive all of the commands output.
// To make sure,  call ChannelReceiveToClose to accumulate any remaining
// output until the server's corresponding "channel close" is received.
success = ssh.ChannelReceiveToClose(channelNum)
If (success <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

cmdOutput = ssh.GetReceivedText(channelNum,"ansi")
If (ssh.LastMethodSuccess <> True) Then
    System.DebugLog(ssh.LastErrorText)
    Return
End If

System.DebugLog(cmdOutput)

// Disconnect
ssh.Disconnect