standards.7: Add some more standards

[thirdparty/man-pages.git] / man7 / sem_overview.7

diff --git a/man7/sem_overview.7 b/man7/sem_overview.7
index 312e4bdaac425eac3b9efab92751ebd99fe15244..cdf7958c56714d6a8cf069005344db736f879cef 100644 (file)
--- a/man7/sem_overview.7
+++ b/man7/sem_overview.7
@@ -1,8 +1,7 @@
 '\" t
-.\" Hey Emacs! This file is -*- nroff -*- source.
-.\"
 .\" Copyright (C) 2006 Michael Kerrisk <mtk.manpages@gmail.com>
 .\"
+.\" %%%LICENSE_START(VERBATIM)
 .\" Permission is granted to make and distribute verbatim copies of this
 .\" manual provided the copyright notice and this permission notice are
 .\" preserved on all copies.
@@ -22,13 +21,14 @@
 .\"
 .\" Formatted or processed versions of this manual, if unaccompanied by
 .\" the source, must acknowledge the copyright and authors of this work.
+.\" %%%LICENSE_END
 .\"
-.TH SEM_OVERVIEW 7 2010-05-22 "Linux" "Linux Programmer's Manual"
+.TH SEM_OVERVIEW 7 2017-05-03 "Linux" "Linux Programmer's Manual"
 .SH NAME
-sem_overview \- Overview of POSIX semaphores
+sem_overview \- overview of POSIX semaphores
 .SH DESCRIPTION
 POSIX semaphores allow processes and threads to synchronize their actions.
-
+.PP
 A semaphore is an integer whose value is never allowed to fall below zero.
 Two operations can be performed on semaphores:
 increment the semaphore value by one
@@ -38,7 +38,7 @@ and decrement the semaphore value by one
 If the value of a semaphore is currently zero, then a
 .BR sem_wait (3)
 operation will block until the value becomes greater than zero.
-
+.PP
 POSIX semaphores come in two forms: named semaphores and
 unnamed semaphores.
 .TP
@@ -61,7 +61,7 @@ followed by one or more characters, none of which are slashes.
 Two processes can operate on the same named semaphore by passing
 the same name to
 .BR sem_open (3).
-
+.IP
 The
 .BR sem_open (3)
 function creates a new named semaphore or opens an existing
@@ -85,13 +85,13 @@ is shared between multiple threads (a
 or processes (a
 .IR "process-shared semaphore" ).
 A thread-shared semaphore is placed in an area of memory shared
-between by the threads of a process, for example, a global variable.
+between the threads of a process, for example, a global variable.
 A process-shared semaphore must be placed in a shared memory region
 (e.g., a System V shared memory segment created using
 .BR shmget (2),
 or a POSIX shared memory object built created using
 .BR shm_open (3)).
-
+.IP
 Before being used, an unnamed semaphore must be initialized using
 .BR sem_init (3).
 It can then be operated on using
@@ -106,7 +106,7 @@ the semaphore should be destroyed using
 The remainder of this section describes some specific details
 of the Linux implementation of POSIX semaphores.
 .SS Versions
-Prior to kernel 2.6, Linux only supported unnamed,
+Prior to kernel 2.6, Linux supported only unnamed,
 thread-shared semaphores.
 On a system with Linux 2.6 and a glibc that provides the NPTL
 threading implementation,
@@ -118,11 +118,11 @@ if not removed by
 a semaphore will exist until the system is shut down.
 .SS Linking
 Programs using the POSIX semaphores API must be compiled with
-.I cc \-lrt
+.I cc \-pthread
 to link against the real-time library,
 .IR librt .
-.SS Accessing named semaphores via the file system
-On Linux, named semaphores are created in a virtual file system,
+.SS Accessing named semaphores via the filesystem
+On Linux, named semaphores are created in a virtual filesystem,
 normally mounted under
 .IR /dev/shm ,
 with names of the form
@@ -132,11 +132,9 @@ with names of the form
 rather than
 .B NAME_MAX
 characters.)
-
+.PP
 Since Linux 2.6.19, ACLs can be placed on files under this directory,
 to control object permissions on a per-user and per-group basis.
-.SH "CONFORMING TO"
-POSIX.1-2001.
 .SH NOTES
 System V semaphores
 .RB ( semget (2),
@@ -149,7 +147,7 @@ on the other hand POSIX semaphores are less widely available
 .SH EXAMPLE
 An example of the use of various POSIX semaphore functions is shown in
 .BR sem_wait (3).
-.SH "SEE ALSO"
+.SH SEE ALSO
 .BR sem_close (3),
 .BR sem_destroy (3),
 .BR sem_getvalue (3),
@@ -158,4 +156,5 @@ An example of the use of various POSIX semaphore functions is shown in
 .BR sem_post (3),
 .BR sem_unlink (3),
 .BR sem_wait (3),
-.BR pthreads (7)
+.BR pthreads (7),
+.BR shm_overview (7)