SSH Quick/Simple Shell Session

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Demonstrates the simplified way to run multiple commands in a shell session using QuickShell, which combines OpenSessionChannel, SendReqPty, and SendReqShell into one call. The commands are built in a StringBuilder, sent together, and the output is read up to a marker echoed by the final command.

load ./chilkat.dll

set success 0

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

#  Demonstrates the simplified way to run multiple commands in a shell session using QuickShell.
#  
#  Note: QuickShell internally does OpenSessionChannel, SendReqPty, and SendReqShell, so it DOES
#  allocate a pseudo-terminal.  The remote shell therefore runs interactively: it prints a
#  command prompt and echoes back the commands that are sent to it.  Both the echoed input and
#  the real output appear in what is received.

set ssh [new_CkSsh]

set port 22
set success [CkSsh_Connect $ssh "ssh.example.com" $port]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

#  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.
set password "mySshPassword"

set success [CkSsh_AuthenticatePw $ssh "mySshLogin" $password]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

#  Start the shell session.  A negative return value indicates failure.
set channelNum [CkSsh_QuickShell $ssh]
if {$channelNum < 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

#  Build the commands, one per line.  Line endings matter: Unix/Linux servers typically expect
#  a bare LF, while Windows servers may require CRLF.
set sbCommands [new_CkStringBuilder]

CkStringBuilder_Append $sbCommands "echo hello world\n"
CkStringBuilder_Append $sbCommands "date\n"
CkStringBuilder_Append $sbCommands "df\n"

#  The final command echoes a marker used to detect the end of the output.  The single quotes
#  around 'IS' are a trick: the terminal echo of the typed command includes the quotes, while
#  the command's actual output does not.  Matching the unquoted form therefore matches the real
#  output rather than the echo.
CkStringBuilder_Append $sbCommands "echo THIS 'IS' THE END OF THE SCRIPT\n"

set commands [CkStringBuilder_getAsString $sbCommands]
set success [CkSsh_ChannelSendString $ssh $channelNum $commands "utf-8"]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringBuilder $sbCommands
    exit
}

#  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.
CkSsh_put_ReadTimeoutMs $ssh 15000

set caseSensitive 1
set success [CkSsh_ChannelReceiveUntilMatch $ssh $channelNum "THIS IS THE END OF THE SCRIPT" "utf-8" $caseSensitive]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringBuilder $sbCommands
    exit
}

#  Indicate that no more commands will be sent, then close the channel.  Close only after the
#  desired output has been received.
set success [CkSsh_ChannelSendEof $ssh $channelNum]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringBuilder $sbCommands
    exit
}

set success [CkSsh_ChannelSendClose $ssh $channelNum]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringBuilder $sbCommands
    exit
}

#  Collect any remaining output.
set success [CkSsh_ChannelReceiveToClose $ssh $channelNum]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringBuilder $sbCommands
    exit
}

set sessionOutput [CkSsh_getReceivedText $ssh $channelNum "utf-8"]
if {[CkSsh_get_LastMethodSuccess $ssh] == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringBuilder $sbCommands
    exit
}

puts "--- output ----"
puts "$sessionOutput"

CkSsh_Disconnect $ssh

delete_CkSsh $ssh
delete_CkStringBuilder $sbCommands