.\"	$NetBSD: _lwp_wakeup.2,v 1.7 2022/12/04 16:21:54 uwe Exp $
.\"
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.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Jason R. Thorpe of Wasabi Systems, Inc.
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.Dd December 4, 2022
.Dt _LWP_WAKEUP 2
.Os
.Sh NAME
.Nm _lwp_wakeup
.Nd make a blocked light-weight process runnable
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In lwp.h
.Ft int
.Fn _lwp_wakeup "lwpid_t lwp"
.Sh DESCRIPTION
.Fn _lwp_wakeup
makes a blocked LWP runnable.  The blocked LWP must be in
.Dv LSSLEEP
state.
Unblocking the LWP does not guarantee that it will make progress; it
may block again as soon as it resumes execution in the kernel.
.Sh RETURN VALUES
.Rt -std _lwp_wakeup
.Sh ERRORS
.Fn _lwp_wakeup
will fail if:
.Bl -tag -width Er
.It Bq Er ESRCH
No LWP can be found in the current process corresponding to that
specified by
.Fa lwp .
.It Bq Er ENODEV
The specified LWP is not in
.Dv LSSLEEP
state.
.It Bq Er EBUSY
The specified LWP is blocked in an uninterruptible sleep.
.El
.Sh HISTORY
The
.Fn _lwp_wakeup
system call first appeared in
.Nx 2.0 .