Lua

Abort a Running SSH Tunnel Operation

Demonstrates the AbortCurrent property, which requests that the currently running foreground operation be aborted. It is intended to be set to true from another thread — for example, to interrupt a synchronous Connect that is waiting for an unresponsive server.

Background: A synchronous call like Connect blocks the calling thread until it finishes or times out, which is a problem when a user clicks "Cancel" or the app needs to shut down. Setting AbortCurrent from a different thread breaks the blocked operation out early, returning a failure the caller can handle. Note its scope is deliberately limited to the current foreground operation: it does not stop the background listener or terminate established tunnel clients — use StopAccepting or CloseTunnel for those.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the SshTunnel.AbortCurrent property, which requests that the currently running
-- foreground operation be aborted.

local tunnel = chilkat.SshTunnel.new()

-- AbortCurrent is intended to be set to true from ANOTHER thread to interrupt a synchronous
-- operation in progress -- for example, a Connect that is waiting for an unresponsive server.
-- It does not stop the background listener or terminate established background tunnel clients.
--
-- The assignment below illustrates the property.  In a real application it would be set on a
-- separate thread while Connect blocks; if it becomes true, the blocked Connect returns with a
-- failure.
tunnel.abort_current = false

tunnel.dest_hostname = "db.internal.example.com"
tunnel.dest_port = 5432

local sshPort = 22
local success = tunnel:connect("ssh.example.com", sshPort)
if not success then
    print(tunnel.last_error_text)
    return
end

print("Connected.")

local waitForThreadExit = true
success = tunnel:close_tunnel(waitForThreadExit)
if not success then
    print(tunnel.last_error_text)
    return
end