SSH Remote Shell with Multiple Commands

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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.

integer li_rc
integer li_Success
oleobject loo_Ssh
string ls_Hostname
integer li_Port
string ls_Password
integer li_ChannelNum
integer li_CaseSensitive
string ls_CmdOutput

li_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.

loo_Ssh = create oleobject
li_rc = loo_Ssh.ConnectToNewObject("Chilkat.Ssh")
if li_rc < 0 then
    destroy loo_Ssh
    MessageBox("Error","Connecting to COM object failed")
    return
end if

ls_Hostname = "ssh.example.com"
li_Port = 22
li_Success = loo_Ssh.Connect(ls_Hostname,li_Port)
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
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.
ls_Password = "mySshPassword"

li_Success = loo_Ssh.AuthenticatePw("mySshLogin",ls_Password)
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

li_ChannelNum = loo_Ssh.OpenSessionChannel()
if li_ChannelNum < 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
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.
li_Success = loo_Ssh.SendReqShell(li_ChannelNum)
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
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.
loo_Ssh.ReadTimeoutMs = 15000

li_CaseSensitive = 1

//  ---- 1st command: change directory ----
li_Success = loo_Ssh.ChannelSendString(li_ChannelNum,"cd /tmp; echo END_OF_CMD_1~n","utf-8")
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

li_Success = loo_Ssh.ChannelReceiveUntilMatch(li_ChannelNum,"END_OF_CMD_1","utf-8",li_CaseSensitive)
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
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.
ls_CmdOutput = loo_Ssh.GetReceivedText(li_ChannelNum,"utf-8")
if loo_Ssh.LastMethodSuccess = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

Write-Debug ls_CmdOutput

//  ---- 2nd command: directory listing ----
li_Success = loo_Ssh.ChannelSendString(li_ChannelNum,"ls; echo END_OF_CMD_2~n","utf-8")
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

li_Success = loo_Ssh.ChannelReceiveUntilMatch(li_ChannelNum,"END_OF_CMD_2","utf-8",li_CaseSensitive)
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

ls_CmdOutput = loo_Ssh.GetReceivedText(li_ChannelNum,"utf-8")
if loo_Ssh.LastMethodSuccess = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

Write-Debug ls_CmdOutput

//  ---- 3rd command: long listing, then finish the session ----
li_Success = loo_Ssh.ChannelSendString(li_ChannelNum,"ls -l~n","utf-8")
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

//  No more input will be sent.
li_Success = loo_Ssh.ChannelSendEof(li_ChannelNum)
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

li_Success = loo_Ssh.ChannelReceiveToClose(li_ChannelNum)
if li_Success = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

ls_CmdOutput = loo_Ssh.GetReceivedText(li_ChannelNum,"utf-8")
if loo_Ssh.LastMethodSuccess = 0 then
    Write-Debug loo_Ssh.LastErrorText
    destroy loo_Ssh
    return
end if

Write-Debug ls_CmdOutput

loo_Ssh.Disconnect()


destroy loo_Ssh