cpython/Lib/idlelib/loader.py
2000-08-15 01:13:23 +00:00

65 lines
2.3 KiB
Python

# Everything is done inside the loader function so that no other names
# are placed in the global namespace. Before user code is executed,
# even this name is unbound.
def loader():
import sys, os, protocol, threading, time
import Remote
## Use to debug the loading process itself:
## sys.stdout = open('c:\\windows\\desktop\\stdout.txt','a')
## sys.stderr = open('c:\\windows\\desktop\\stderr.txt','a')
# Ensure that there is absolutely no pollution of the global
# namespace by deleting the global name of this function.
global loader
del loader
# Connect to IDLE
try:
client = protocol.Client()
except protocol.connectionLost, cL:
print 'loader: Unable to connect to IDLE', cL
return
# Connect to an ExecBinding object that needs our help. If
# the user is starting multiple programs right now, we might get a
# different one than the one that started us. Proving that's okay is
# left as an exercise to the reader. (HINT: Twelve, by the pigeonhole
# principle)
ExecBinding = client.getobject('ExecBinding')
if not ExecBinding:
print "loader: IDLE does not need me."
return
# All of our input and output goes through ExecBinding.
sys.stdin = Remote.pseudoIn( ExecBinding.readline )
sys.stdout = Remote.pseudoOut( ExecBinding.write.void, tag="stdout" )
sys.stderr = Remote.pseudoOut( ExecBinding.write.void, tag="stderr" )
# Create a Remote object and start it running.
remote = Remote.Remote(globals(), ExecBinding)
rthread = threading.Thread(target=remote.mainloop)
rthread.setDaemon(1)
rthread.start()
# Block until either the client or the user program stops
user = rthread.isAlive
while user and client.isAlive():
time.sleep(0.025)
if not user():
user = hasattr(sys, "ready_to_exit") and sys.ready_to_exit
for t in threading.enumerate():
if not t.isDaemon() and t.isAlive() and t!=threading.currentThread():
user = t.isAlive
break
# We need to make sure we actually exit, so that the user doesn't get
# stuck with an invisible process. We want to finalize C modules, so
# we don't use os._exit(), but we don't call sys.exitfunc, which might
# block forever.
del sys.exitfunc
sys.exit()
loader()