Replace process.api with Event

sys/etc/scripts/follow

@@ -2,8 +2,8 @@ local function follow(id)
 
   require = requireInjector(getfenv(1))
   local Socket = require('socket')
-  local Point = require('point')
-  local process = require('process')
+  local Point  = require('point')
+  local Event  = require('event')
 
   turtle.status = 'follow ' .. id
 
@@ -20,90 +20,86 @@ local function follow(id)
   local lastPoint
   local following = false
 
-  local followThread = process:newThread('follower', function()
-    while true do
+  Event.on('turtle_follow', function(_, pt)
 
-      local function getRemotePoint()
-        if not turtle.abort then
-          if socket:write({ type = 'gps' }) then
-            return socket:read(3)
-          end
+    local pts = {
+      { x = pt.x + 2, z = pt.z,     y = pt.y },
+      { x = pt.x - 2, z = pt.z,     y = pt.y },
+      { x = pt.x,     z = pt.z + 2, y = pt.y },
+      { x = pt.x,     z = pt.z - 2, y = pt.y },
+    }
+
+    local cpt = Point.closest(turtle.point, pts)
+
+    local blocks = { }
+
+    local function addBlocks(tpt)
+      table.insert(blocks, tpt)
+      local apts = Point.adjacentPoints(tpt)
+      for _,apt in pairs(apts) do
+        table.insert(blocks, apt)
+      end
+    end
+
+    -- don't run into player
+    addBlocks(pt)
+    addBlocks({ x = pt.x, z = pt.z, y = pt.y + 1 })
+
+    if turtle.pathfind(cpt, blocks) then
+      turtle.headTowards(pt)
+    end
+    following = false
+  end)
+
+  Event.onInterval(.5, function()
+
+    local function getRemotePoint()
+      if not turtle.abort then
+        if socket:write({ type = 'gps' }) then
+          return socket:read(3)
         end
       end
+    end
 
-      -- sometimes gps will fail if moving
-      local pt, d
+    -- sometimes gps will fail if moving
+    local pt, d
 
-      for i = 1, 3 do
-        pt, d = getRemotePoint()
-        if pt then
-          break
-        end
-        os.sleep(.5)
+    for i = 1, 3 do
+      pt, d = getRemotePoint()
+      if pt then
+        break
       end
-
-      if not pt or turtle.abort then
-        error('Did not receive GPS location')
-      end
-
-      if not lastPoint or (lastPoint.x ~= pt.x or lastPoint.y ~= pt.y or lastPoint.z ~= pt.z) then
-
-        if following then
-          turtle.abort = true
-          while following do
-            os.sleep(.1)
-          end
-          turtle.abort = false
-        end
-
-        -- check if gps is inaccurate (player moving too fast)
-        if d < Point.pythagoreanDistance(turtle.point, pt) + 10 then
-          lastPoint = Point.copy(pt)
-          following = true
-          process:newThread('turtle_follow', function()
-
-            local pts = {
-              { x = pt.x + 2, z = pt.z,     y = pt.y },
-              { x = pt.x - 2, z = pt.z,     y = pt.y },
-              { x = pt.x,     z = pt.z + 2, y = pt.y },
-              { x = pt.x,     z = pt.z - 2, y = pt.y },
-            }
-
-            local cpt = Point.closest(turtle.point, pts)
-
-            local blocks = { }
-
-            local function addBlocks(tpt)
-              table.insert(blocks, tpt)
-              local apts = Point.adjacentPoints(tpt)
-              for _,apt in pairs(apts) do
-                table.insert(blocks, apt)
-              end
-            end
-
-            -- don't run into player
-            addBlocks(pt)
-            addBlocks({ x = pt.x, z = pt.z, y = pt.y + 1 })
-
-            if turtle.pathfind(cpt, blocks) then
-              turtle.headTowards(pt)
-            end
-            following = false
-          end)
-        end
-      end
-
       os.sleep(.5)
     end
+
+    if not pt or turtle.abort then
+      error('Did not receive GPS location')
+    end
+
+    if not lastPoint or (lastPoint.x ~= pt.x or lastPoint.y ~= pt.y or lastPoint.z ~= pt.z) then
+
+      if following then
+        turtle.abort = true
+        while following do
+          os.sleep(.1)
+        end
+        turtle.abort = false
+      end
+
+      -- check if gps is inaccurate (player moving too fast)
+      if d < Point.pythagoreanDistance(turtle.point, pt) + 10 then
+        lastPoint = Point.copy(pt)
+        following = true
+        os.queueEvent('turtle_follow', pt)
+      end
+    end
   end)
 
-  while true do
-    local e = process:pullEvent()
-    if e == 'terminate' or followThread:isDead() or e =='turtle_abort' then
-      process:threadEvent('terminate')
-      break
-    end
-  end
+  Event.on('turtle_abort', function()
+    Event.exitPullEvents()
+  end)
+
+  Event.pullEvents()
 
   socket:close()
 
@@ -114,4 +110,3 @@ local s, m = turtle.run(function() follow({COMPUTER_ID}) end)
 if not s and m then
   error(m)
 end
-