--- a/hglib.lua	Wed Sep 07 21:15:06 2016 +0800
+++ b/hglib.lua	Thu Sep 08 13:03:21 2016 +0800
@@ -1,3 +1,5 @@
+local lpc = require('lpc')
+
 local sizes = { i4 = 4, u4 = 4, c = 1 }
 
 local function read_u4(rh)
@@ -31,9 +33,28 @@
 	setmetatable(client, Client)
 	client.rh = rh
 	client.wh = wh
+	client:read_hello()
 	return client
 end
 
+function Client.open(repo)
+	local cmd = { 'hg', 'serve', '--cmdserver', 'pipe', '--config', 'ui.interactive=True' }
+	if repo ~= nil then
+		table.insert(cmd, '-R')
+		table.insert(cmd, repo)
+	end
+	local pid, wh, rh = lpc.run(unpack(cmd))
+	local client = Client.connect(rh, wh)
+	client.lpcpid = pid
+	return client
+end
+
+function Client:close()
+	if self.wh ~= nil then self.wh:close() end
+	if self.rh ~= nil then self.rh:close() end
+	if self.lpcpid ~= nil then lpc.wait(self.lpcpid) end
+end
+
 function Client:read_hello()
 	local channel, message = read_channel(self.rh)
 	assert(channel == 'o', 'channel for the hello message must be "o"')

--- a/spec/hglib_spec.lua	Wed Sep 07 21:15:06 2016 +0800
+++ b/spec/hglib_spec.lua	Thu Sep 08 13:03:21 2016 +0800
@@ -1,10 +1,9 @@
 local hglib = require('hglib')
 
 describe('hglib client', function()
-	it('can read hello', function()
+	it('can connect using just file handles', function()
 		local rh = io.open('spec/data/hello', 'rb')
 		local client = hglib.Client.connect(rh, nil)
-		client:read_hello()
 		rh:close()
 		assert.is_true(client.capabilities.getencoding)
 		assert.is_true(client.capabilities.runcommand)
@@ -12,4 +11,14 @@
 		assert.are_equal(3615, client.pid)
 		assert.are_equal(3615, client.pgid)
 	end)
+
+	it('can launch a new cmdserver process', function()
+		local client = hglib.Client.open()
+		assert.is_true(client.capabilities.getencoding)
+		assert.is_true(client.capabilities.runcommand)
+		assert.are_equal('UTF-8', client.encoding)
+		assert.are_equal('number', type(client.pid))
+		assert.are_equal('number', type(client.lpcpid))
+		client:close()
+	end)
 end)