(Lianja) Multiple SendReqExec on Same Connection

Shows how to execute a series of commands on an SSH server and retrieve each command's output (using SendReqExec). Each call to SendReqExec requires its own logical channel. This is not a separate SSH connection -- it's simply a new session channel on the existing SSH connection.

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

loSsh = createobject("CkSsh")

// Hostname may be an IP address or domain:
lcHostname = "172.16.16.46"
lnPort = 22

llSuccess = loSsh.Connect(lcHostname,lnPort)
if (llSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// If receiving output from a command stalls for more than 5 seconds, then stop waiting.
loSsh.IdleTimeoutMs = 5000

// Authenticate using login/password:
llSuccess = loSsh.AuthenticatePw("myLogin","myPassword")
if (llSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Open a session channel.  (It is possible to have multiple
// session channels open simultaneously.)
lnChannelNum = loSsh.OpenSessionChannel()
if (lnChannelNum < 0) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Request a directory listing on the remote server:
// If your server is Linux/UNIX, change the string from "dir" to "ls"
// Note: Some SSH servers require a CRLF instead of a bare-LF
lcCmd = "ls -al" + Chr(10)
llSuccess = loSsh.SendReqExec(lnChannelNum,lcCmd)
if (llSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// 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.
lnPollTimeoutMs = 2000
n = loSsh.ChannelReadAndPoll(lnChannelNum,lnPollTimeoutMs)
if (n < 0) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Close the channel:
llSuccess = loSsh.ChannelSendClose(lnChannelNum)
if (llSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// 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.
llSuccess = loSsh.ChannelReceiveToClose(lnChannelNum)
if (llSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Get the accumulated output of the command:

lcCmdOutput = loSsh.GetReceivedText(lnChannelNum,"ansi")
if (loSsh.LastMethodSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Display the remote shell's command output:
? lcCmdOutput
? "----"

// -----------------------------------------------------------------
// Now for the 2nd SendReqExe (on the same connection,
// but on a separate logical channel).
// -----------------------------------------------------------------

lnChannelNum = loSsh.OpenSessionChannel()
if (lnChannelNum < 0) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

lcCmd = "nslookup chilkatsoft.com" + Chr(10)
llSuccess = loSsh.SendReqExec(lnChannelNum,lcCmd)
if (llSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

lnPollTimeoutMs = 2000
n = loSsh.ChannelReadAndPoll(lnChannelNum,lnPollTimeoutMs)
if (n < 0) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

llSuccess = loSsh.ChannelSendClose(lnChannelNum)
if (llSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

llSuccess = loSsh.ChannelReceiveToClose(lnChannelNum)
if (llSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

lcCmdOutput = loSsh.GetReceivedText(lnChannelNum,"ansi")
if (loSsh.LastMethodSuccess = .F.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

? lcCmdOutput


release loSsh