Module Name: src
Committed By: uwe
Date: Thu Sep 23 13:16:13 UTC 2021
Modified Files:
src/lib/libc/sys: eventfd.2
Log Message:
Markup fixes.
To generate a diff of this commit:
cvs rdiff -u -r1.1 -r1.2 src/lib/libc/sys/eventfd.2
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/libc/sys/eventfd.2
diff -u src/lib/libc/sys/eventfd.2:1.1 src/lib/libc/sys/eventfd.2:1.2
--- src/lib/libc/sys/eventfd.2:1.1 Sun Sep 19 15:51:28 2021
+++ src/lib/libc/sys/eventfd.2 Thu Sep 23 13:16:13 2021
@@ -1,4 +1,4 @@
-.\" $NetBSD: eventfd.2,v 1.1 2021/09/19 15:51:28 thorpej Exp $
+.\" $NetBSD: eventfd.2,v 1.2 2021/09/23 13:16:13 uwe Exp $
.\"
.\" Copyright (c) 2021 The NetBSD Foundation, Inc.
.\" All rights reserved.
@@ -30,11 +30,15 @@
.Dd September 17, 2021
.Dt EVENTFD 2
.Os
+.\"
+.\"
.Sh NAME
.Nm eventfd ,
.Nm eventfd_read ,
.Nm eventfd_write
.Nd create and interact with a counting event descriptor
+.\"
+.\"
.Sh SYNOPSIS
.In sys/eventfd.h
.Ft int
@@ -43,6 +47,8 @@
.Fn eventfd_read "int efd" "eventfd_t *valp"
.Ft int
.Fn eventfd_write "int efd" "eventfd_t val"
+.\"
+.\"
.Sh DESCRIPTION
The
.Nm
@@ -52,10 +58,7 @@ respectively.
When the object's value is non-zero, the file descriptor is considered
.Dq readable ,
and when the count is less than the maximum value
-.Po
-.Dv UINT64_MAX
-- 1
-.Pc
+.Li UINT64_MAX\^-\^1
it is considered
.Dq writable .
When an
@@ -65,11 +68,11 @@ object is no longer needed, it may be di
.Pp
All I/O to an
.Nm
-object is 8 bytes in length, which is the space required to store an
+object is 8\~bytes in length, which is the space required to store an
unsigned 64-bit integer.
-Any read or write with a buffer smaller than 8 bytes will fail with
-.Dv EINVAL .
-Only the first 8 bytes of the buffer will be used.
+Any read or write with a buffer smaller than 8\~bytes will fail with
+.Er EINVAL .
+Only the first 8\~bytes of the buffer will be used.
.Pp
The
.Fn eventfd
@@ -79,7 +82,7 @@ The initial value of the object is speci
.Fa val
argument.
The following flags define the behavior of the resulting object:
-.Bl -tag -width "EFD_SEMAPHORE"
+.Bl -tag -width Dv
.It Dv EFD_CLOEXEC
This is an alias for the
.Dv O_CLOEXEC
@@ -111,24 +114,20 @@ If the
.Nm
object was created in
.Dq semaphore mode ,
-reads return the value
-.Dv 1
-and object's counter is decremented by
-.Dv 1 .
+reads return the value\~1
+and object's counter is decremented by\~1.
.It
If the
.Nm
object was not created in
.Dq semaphore mode ,
reads return the current value of the object's counter
-reset the counter to
-.Dv 0 .
+and reset the counter to\~0.
.El
.Pp
If the value of the
.Nm
-object's counter is
-.Dv 0 ,
+object's counter is\~0,
then reads will block, unless the
.Nm
object is set for non-blocking I/O.
@@ -155,37 +154,32 @@ objects, and are simply wrappers around
and
.Xr write 2
system calls:
-.Bl -tag -width "eventfd_writeXX"
-.It Fn eventfd_read
+.Bl -tag -width Fn
+.It Fn eventfd_read efd valp
Reads the unsigned 64-bit integer value of the
.Nm
object and returns it in
.Fa valp .
-.It Fn eventfd_write
+.It Fn eventfd_write efd val
Writes the unsigned 64-bit integer value
.Fa val
to the
.Nm
object.
.El
+.\"
+.\"
.Sh RETURN VALUES
The
.Fn eventfd
-system call returns
-.Dv -1
-if an error occurs, otherwise the return value is a descriptor representing the
+system call returns\~\-1 if an error occurs,
+otherwise the return value is a descriptor representing the
.Nm
object.
.Pp
-The
-.Fn eventfd_read
-and
-.Fn eventfd_write
-functions return
-.Dv 0
-upon success or
-.Dv -1
-if an error occurs.
+.Rv -std eventfd_read eventfd_write
+.\"
+.\"
.Sh ERRORS
The
.Fn eventfd
@@ -213,9 +207,7 @@ function fails if:
.It Bq Er EAGAIN
The value of the
.Nm
-object is
-.Dv 0
-and the
+object is\~0 and the
.Nm
object is set for non-blocking I/O.
.El
@@ -230,10 +222,7 @@ The resulting value of the
object after adding the value
.Fa val
would exceed the maximum value
-.Po
-.Dv UINT64_MAX
-- 1
-.Pc
+.Li UINT64_MAX\^-\^1
and the
.Nm
object is set for non-blocking I/O.
@@ -250,9 +239,11 @@ a read from or write to an
object fails if:
.Bl -tag -width Er
.It Bq Er EINVAL
-The size of the buffer is less than 8 bytes
+The size of the buffer is less than 8\~bytes
.Pq the size required to hold an unsigned 64-bit integer .
.El
+.\"
+.\"
.Sh SEE ALSO
.Xr close 2 ,
.Xr kevent 2 ,
@@ -261,6 +252,8 @@ The size of the buffer is less than 8 by
.Xr read 2 ,
.Xr select 2 ,
.Xr write 2
+.\"
+.\"
.Sh HISTORY
The
.Nm
