[[!meta copyright="Copyright © 2009, 2010 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled [[GNU Free Documentation License|/fdl]]."]]"""]] The GNU Hurd uses a similar concept to [[UNIX processes|unix/process]]. As a [[Mach task|microkernel/mach/task]] only implements a part of a UNIX process, there is additional work to be done, for example for [[signal]]s, [[environment_variable]]s, [[file_descriptor]]s. # Controlling TTY Hurd controlling tty behavior is generally consistent with BSD's, including `TIOCSCTTY`. Linux also has `TIOCSCTTY` and it is harmless to use it there. But BSD and Hurd never do an implicit `TIOCSCTTY` (hence our `O_NOCTTY` is zero). C.f. and the following messages.