buf.tofile(files.stdout)

					write_successful = False

					files.stdout.flush()

					failures = 0

					while True:

						try:

							if not write_successful:

								buf.tofile(files.stdout)

								write_successful = True

							files.stdout.flush()

							break

						except IOError, e:

							if e.errno != errno.EAGAIN:

								raise

							del e

							failures += 1

							if failures > 50:

								# Avoid a potentially infinite loop. In

								# most cases, the failure count is zero

								# and it's unlikely to exceed 1.

								raise

							# This means that a subprocess has put an inherited

							# stdio file descriptor (typically stdin) into

							# O_NONBLOCK mode. This is not acceptable (see bug

							# #264435), so revert it. We need to use a loop

							# here since there's a race condition due to

							# parallel processes being able to change the

							# flags on the inherited file descriptor.

							# TODO: When possible, avoid having child processes

							# inherit stdio file descriptors from portage

							# (maybe it can't be avoided with

							# PROPERTIES=interactive).

							fcntl.fcntl(files.stdout.fileno(), fcntl.F_SETFL,

								fcntl.fcntl(files.stdout.fileno(),

								fcntl.F_GETFL) ^ os.O_NONBLOCK)