New way of generating .pyc files, thanks to Sjoerd.

urllib.py: '+' is not always safe (even though the RFC says so :-( )
whrandom.py: throw away top bits of time to avoid overflow on Mac
(where times can be negative)

Lib/compileall.py

@@ -0,0 +1,67 @@
+# Routines to force "compilation" of all .py files in a directory
+# tree or on sys.path.  By default recursion is pruned at a depth of
+# 10 and the current directory, if it occurs in sys.path, is skipped.
+# When called as a script, compiles argument directories, or sys.path
+# if no arguments.
+# After a similar module by Sjoerd Mullender.
+
+import os
+import sys
+import py_compile
+
+def compile_dir(dir, maxlevels = 10):
+	print 'Listing', dir, '...'
+	try:
+		names = os.listdir(dir)
+	except os.error:
+		print "Can't list", dir
+		names = []
+	names.sort()
+	for name in names:
+		fullname = os.path.join(dir, name)
+		if os.path.isfile(fullname):
+			head, tail = name[:-3], name[-3:]
+			if tail == '.py':
+				print 'Compiling', fullname, '...'
+				try:
+					py_compile.compile(fullname)
+				except KeyboardInterrupt:
+					del names[:]
+					print '\n[interrupt]'
+					break
+				except:
+					print 'Sorry:', sys.exc_type + ':',
+					print sys.exc_value
+		elif maxlevels > 0 and \
+		     name != os.curdir and name != os.pardir and \
+		     os.path.isdir(fullname) and \
+		     not os.path.islink(fullname):
+			compile_dir(fullname, maxlevels - 1)
+
+def compile_path(skip_curdir = 1):
+	for dir in sys.path:
+		if dir == os.curdir and skip_curdir:
+			print 'Skipping current directory'
+		else:
+			compile_dir(dir, 0)
+
+def main():
+	import getopt
+	try:
+		opts, args = getopt.getopt(sys.argv[1:], 'l')
+	except getopt.error, msg:
+		print msg
+		print "usage: compileall [-l] [directory ...]"
+		print "-l: don't recurse down"
+		print "if no arguments, -l sys.path is assumed"
+	maxlevels = 10
+	for o, a in opts:
+		if o == '-l': maxlevels = 0
+	if args:
+		for dir in sys.argv[1:]:
+			compile_dir(dir, maxlevels)
+	else:
+		compile_path()
+
+if __name__ == '__main__':
+	main()