diff options
Diffstat (limited to 'lib/libc/sys/nanosleep.2')
| -rw-r--r-- | lib/libc/sys/nanosleep.2 | 94 |
1 files changed, 58 insertions, 36 deletions
diff --git a/lib/libc/sys/nanosleep.2 b/lib/libc/sys/nanosleep.2 index 63e4e4e365b..fc2bffb9a9d 100644 --- a/lib/libc/sys/nanosleep.2 +++ b/lib/libc/sys/nanosleep.2 @@ -1,4 +1,4 @@ -.\" $OpenBSD: nanosleep.2,v 1.16 2018/12/31 18:54:00 cheloha Exp $ +.\" $OpenBSD: nanosleep.2,v 1.17 2021/07/23 12:47:21 cheloha Exp $ .\" $NetBSD: nanosleep.2,v 1.1 1997/04/17 18:12:02 jtc Exp $ .\" .\" Copyright (c) 1986, 1991, 1993 @@ -30,7 +30,7 @@ .\" .\" @(#)sleep.3 8.1 (Berkeley) 6/4/93 .\" -.Dd $Mdocdate: December 31 2018 $ +.Dd $Mdocdate: July 23 2021 $ .Dt NANOSLEEP 2 .Os .Sh NAME @@ -41,53 +41,69 @@ .Ft int .Fn nanosleep "const struct timespec *timeout" "struct timespec *remainder" .Sh DESCRIPTION +The .Fn nanosleep -suspends execution of the calling process for the duration specified by +function suspends execution of the calling thread for at least the given .Fa timeout . -An unmasked signal will cause it to terminate the sleep early, -regardless of the +Delivery of an unmasked signal terminates this sleep early, +even if .Dv SA_RESTART -value on the interrupting signal. +is set with +.Xr sigaction 2 +for the interrupting signal. .Sh RETURN VALUES -If the +If .Fn nanosleep -function returns because the requested duration has elapsed, the value -returned will be zero. +sleeps the full +.Fa timeout +without interruption it returns 0. +Unless +.Fa remainder +is +.Dv NULL , +it is set to zero. .Pp -If the +If .Fn nanosleep -function returns due to the delivery of a signal, the value returned -will be \-1, and the global variable +is interrupted by a signal it returns \-1 and the global variable .Va errno -will be set to indicate the interruption. -If +is set to +.Dv EINTR . +Unless .Fa remainder -is non-null, the timespec structure it references is updated to contain the -unslept amount (the requested duration minus the duration actually slept). -.Sh ERRORS -If any of the following conditions occur, the +is +.Dv NULL , +it is set to the unslept portion of the +.Fa timeout . +.Pp +Otherwise, .Fn nanosleep -function shall return \-1 and set +returns \-1 and the global variable .Va errno -to the corresponding value. +is set to indicate the error. +.Sh ERRORS +.Fn nanosleep +will fail if: .Bl -tag -width Er .It Bq Er EINTR -.Fn nanosleep -was interrupted by the delivery of a signal. +The call is interrupted by the delivery of a signal. .It Bq Er EINVAL .Fa timeout -specified a nanosecond value less than zero or greater than or equal to -1000 million, +specifies a nanosecond value less than zero or greater than or equal to +one billion, or a second value less than zero. .It Bq Er EFAULT -Either .Fa timeout -or -.Fa remainder points to memory that is not a valid part of the process address space. +.It Bq Er EFAULT +.Fa remainder +is not +.Dv NULL +and points to memory that is not a valid part of the process address space. .El .Sh SEE ALSO .Xr sleep 1 , +.Xr sigaction 2 , .Xr sleep 3 .Sh STANDARDS The @@ -97,17 +113,23 @@ function conforms to .Sh HISTORY The predecessor of this system call, .Fn sleep , -appeared in -.At v3 , -but was removed when +first appeared in +.At v3 . +It was removed in +.At v7 +and replaced with a C library implementation based on .Xr alarm 3 -was introduced into -.At v7 . +and +.Xr signal 3 . +.Pp The .Fn nanosleep -system call has been available since +function first appeared in +.St -p1003.1b-93 . +.Pp +This implementation of +.Fn nanosleep +first appeared in .Nx 1.3 and was ported to -.Ox 2.1 -and -.Fx 3.0 . +.Ox 2.1 . |