(Go) 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 Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

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

    ssh := chilkat.NewSsh()

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

    var cmdOutput *string = new(string)

    // Connect to an SSH server:
    var hostname string
    var port int

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

    success := ssh.Connect(hostname,port)
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // Wait a max of 10 seconds when reading responses..
    ssh.SetIdleTimeoutMs(10000)

    // Authenticate using login/password:
    success = ssh.AuthenticatePw("myLogin","myPassword")
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // Open a session channel.  (It is possible to have multiple
    // session channels open simultaneously.)
    var channelNum int
    channelNum = ssh.OpenSessionChannel()
    if channelNum < 0 {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    termType := "dumb"
    widthInChars := 120
    heightInChars := 40
    // Use 0 for pixWidth and pixHeight when the dimensions
    // are set in number-of-chars.
    pixWidth := 0
    pixHeight := 0
    success = ssh.SendReqPty(channelNum,termType,widthInChars,heightInChars,pixWidth,pixHeight)
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // Start a shell on the channel:
    success = ssh.SendReqShell(channelNum)
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    //  Run the 1st command in the remote shell, which will be to
    //  "cd" to a subdirectory.
    success = ssh.ChannelSendString(channelNum,"cd workspace\r\n","ansi")
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // Retrieve the output.
    success = ssh.ChannelReceiveUntilMatch(channelNum,myPrompt,"ansi",true)
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    //  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 {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    fmt.Println(*cmdOutput)

    //  Run the 2nd command in the remote shell, which will be
    //  to "ls" the directory.
    success = ssh.ChannelSendString(channelNum,"ls\r\n","ansi")
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // Retrieve and display the output.
    success = ssh.ChannelReceiveUntilMatch(channelNum,myPrompt,"ansi",true)
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    cmdOutput = *ssh.GetReceivedText(channelNum,"ansi")
    if ssh.LastMethodSuccess() != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    fmt.Println(*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\r\n","ansi")
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // 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 {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // 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.
    var n int
    pollTimeoutMs := 2000
    n = ssh.ChannelReadAndPoll(channelNum,pollTimeoutMs)
    if n < 0 {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // Close the channel:
    success = ssh.ChannelSendClose(channelNum)
    if success != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    // 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 {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    cmdOutput = *ssh.GetReceivedText(channelNum,"ansi")
    if ssh.LastMethodSuccess() != true {
        fmt.Println(ssh.LastErrorText())
        ssh.DisposeSsh()
        return
    }

    fmt.Println(*cmdOutput)

    // Disconnect
    ssh.Disconnect()

    ssh.DisposeSsh()