coroutine yeilding and sleep( )

process = {}
process.running = {}
function process.create( name, func ) --this creates a process that can be run later
local func = coroutine.create( func ) --creates a coroutine of the function passed in
process.running[name] = { } --makes a new slot in the process.running table for the process
process.running[name].window = window.getFree( ) --sets the slot of the window it will use
window.create( window.getFree( ) ) --makes a new window at the slot
process.running[name].co = func --sets the processes coroutine to the function passed in
end --ends the function
function process.getIndex( name, t ) --returns the index of a process
t = t or process.running --makes sure t exists
local i = 1 --sets i to 1
for k,v in pairs( t ) do --goes through all the coroutines
  if k == name then --checks if the process its at is the one the user is looking for
   return i --returns the index
  end
  local i = i+1 --goes to the next index
end
end
function process.run( name ) --runs a process
if coroutine.status( process.running[name].co ) == "dead" then --checks if its dead
  local k = process.getIndex( name, process.running ) --gets the index of the dead process
  if not k then error( "wierd" ) end --errors if it cannot find the index of a process
  table.remove( window.s, process.running[name].window ) --removes the processes window
  table.remove( process.running, k ) --removes the process
else
  coroutine.resume( process.running[name].co ) --runs the process
end
end
window = {}
window.s = { }
function window.getFree( ) --returns the first free slot
local i = 1 --sets i to 1
while true do --loops
  if not window.s[i] then --if the slot is free then
   return i --returns the index
  end
  i = i+1
  if i > 500 then --checks if it has been running too long
   return --quits the loop
  end
end
error( "no windows left" ) --errors if it cannot find a free window
end
function window.genScreen( x, y, bc, tc ) --generates a new screen
for i = 1, y do --loops through y
  screen[i] = { } --sets the y to a table
  for m = 1, x do --loops through x
   screen[i][m] = { [1] = " ", [2] = bc, [3] = tc } --sets the x to a table containing draw data
   return screen --returns the result
  end
end
error( "failed to generate screen" ) --errors if it failed to do any of the above
end
function window.create( index, x, y, bc, tc, screen, xpos, ypos ) --creates a new window
local index = index or window.getFree( ) --if no index is passed on it sets the index to the first one available
local x = x or 51 --goes through all the variables making sure they exist
local y = y or 19
local bc = bc or colours.black
local tc = tc or 1
local xpos = xpos or 1
local ypos = ypos or 1
local screen = window.genScreen( x, y, bc, tc ) --generates a screen
table.insert( window.s, index, { screen = screen, bc = bc, tc = tc, x = xpos, y = ypos } ) --inserts the window into the window.s table
end
function window.write( index, ... ) --puts strings into the window.s[index].screen table
local str = ""
for i = 1,#arg do
  str = str..tostring( arg[i] ) --joins all the args into 1 string
end
local len = string.len( str ) --gets the length of the string
local m = { }
for i = 1,len do
  table.insert( m, string.sub( str, i, i ) ) --splits all the chars into a table
end
local win = window.s[index] --sets win to the window selected table
for i = 1,#m do
  if ( i+win.x )-1 <= 51 then --makes sure it will not go off screen
   win.screen[win.y][( i+win.x )-1] = { [1] = m[i], [2] = win.bc, [3] = win.tc } --inserts the char into the processes screen
  end
end
end
screen = { }
function screen.draw( ) --draws all the screens ( will be updated )
for i = 1,#window.s do
  local s = window.s[i].screen
  for m = 1,#s do
   for k = 1,#s[m] do
	oldTerm.setCursorPos( k, m ) --sets the cursor pos
	oldTerm.setBackgroundColour( s[m][k][2] ) --sets the colour
	oldTerm.setTextColour( s[m][k][3] ) --sets the other colour
	oldTerm.write( s[m][k][1] ) --writes the char
   end
  end
end
end
oldTerm = _G["term"] --sets oldTerm to term
term = { } --removes term
function term.write( ... ) --rewrites term ( puts it into the files screen )
local prog = shell.getRunningProgram( ) --gets the file/program its being called from
if process.running[prog] then --checks if there is a process for it
  window.write( process.running[prog].window, unpack( arg ) ) --writes it
  screen.draw( ) --draws the screen
else
  error( "unknown application tried to draw to screen" ) --errors that there was no process for the function
end
end
function term.clear( )
local prog = shell.getRunningProgram( ) --gets the running program
if process.running[prog] then --checks of there is a process for it
  local win = process.running[prog].window --gets the window for the process
  window.s[win].screen = window.genScreen( #window.s[win].screen, #window.s[win].screen[1], window.s[win].bc, window.s[win].tc ) --resets it
  screen.draw( ) --draws the screen
else
  error( "unknown application tried to draw to screen" )
end
end
--the rest of the term functions will come later ( they aren't very complicated )
function runProgram( path )
process.create( path, function() shell.run( path ) end ) --creates a process for a program/file
end
runProgram( "hello" )
for z = 1,10 do
process.run( "hello" )
sleep( 0.1 )
end
term = { }
term = oldTerm