mirror of
https://git.rtems.org/rtems-docs/
synced 2025-05-31 08:11:24 +08:00
2c3cf2166d
This is a replacement of the POSIX 1003.1 Compliance Guide. It will be generated from a .csv file. Updates #3177.
34 lines
1.6 KiB
ReStructuredText
34 lines
1.6 KiB
ReStructuredText
.. comment SPDX-License-Identifier: CC-BY-SA-4.0
|
|
|
|
.. COMMENT: COPYRIGHT (c) 1988-2017.
|
|
.. COMMENT: On-Line Applications Research Corporation (OAR).
|
|
.. COMMENT: All rights reserved.
|
|
|
|
Preface
|
|
=======
|
|
|
|
RTEMS supports a variety of POSIX and BSD features including some POSIX
|
|
methods that are now deemed obsolete and some methods for compatibility
|
|
with GNU/Linux and FreeBSD. There are multiple POSIX standard versions
|
|
as well as multiple efforts to tailor (e.g. profile) POSIX for embedded
|
|
environments. They range in size from less than 200 required capabilities
|
|
to the full POSIX standard which has over 1200 required capabilities. This
|
|
document reports on the alignment of RTEMS with various standard versions
|
|
and defined profiles.
|
|
|
|
RTEMS supports a number of POSIX process, user, and group oriented
|
|
routines in what is referred to as a "SUSP" (Single-User, Single
|
|
Process) manner. RTEMS supports a single process, multithreaded
|
|
POSIX environment. In a pure world, there would be no reason to even
|
|
include routines like ``getpid()`` when there can only be one process.
|
|
But providing routines like ``getpid()`` and making them work in
|
|
a sensible fashion for an embedded environment while not returning
|
|
``ENOSYS`` (for not implemented) makes it significantly easier to port
|
|
code from a UNIX environment without modifying it.
|
|
|
|
Each chapter in this document presents the alignment of RTEMS with
|
|
a specific standard version or defined profile. Each section with a
|
|
chapter details the alignment of a specific header file relative to the
|
|
chapter's standard or profile. The implementation status of the items
|
|
required by the standard are listed.
|