Index: lib/libc/sys/mq_unlink.3
===================================================================
--- /dev/null
+++ lib/libc/sys/mq_unlink.3
@@ -0,0 +1,121 @@
+.\" Copyright (c) 2021 Fernando Apesteguia <fernape@FreeBSD.org>
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice(s), this list of conditions and the following disclaimer as
+.\"    the first lines of this file unmodified other than the possible
+.\"    addition of one or more copyright notices.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice(s), this list of conditions and the following disclaimer in
+.\"    the documentation and/or other materials provided with the
+.\"    distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
+.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
+.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" Portions of this text are reprinted and reproduced in electronic form
+.\" from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology --
+.\" Portable Operating System Interface (POSIX), The Open Group Base
+.\" Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of
+.\" Electrical and Electronics Engineers, Inc and The Open Group.  In the
+.\" event of any discrepancy between this version and the original IEEE and
+.\" The Open Group Standard, the original IEEE and The Open Group Standard is
+.\" the referee document.  The original Standard can be obtained online at
+.\"	http://www.opengroup.org/unix/online.html.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd February 15, 2021
+.Dt MQ_UNLINK 3
+.Os
+.Sh NAME
+.Nm mq_unlink
+.Nd "mq_unlink - remove a message queue (REALTIME)"
+.Sh LIBRARY
+.Lb librt
+.Sh SYNOPSIS
+.In mqueue.h
+.Ft int
+.Fn mq_unlink "const char *name"
+.Sh DESCRIPTION
+The
+.Fn mq_unlink
+function removes the message queue named by the string
+.Fa name .
+If one or more processes have the message queue open when
+.Fn mq_unlink
+is called, destruction of the message queue will be postponed
+until all references to the message queue have been closed.
+However, the
+.Fn mq_unlink
+call need not block until all references have been closed; it may return
+immediately.
+.Pp
+After a successful call to
+.Fn mq_unlink ,
+reuse of the name will subsequently cause
+.Xr mq_open 2
+to behave as if no message queue of this name exists.
+.Sh RETURN VALUES
+.Rv -std
+.Sh ERRORS
+The
+.Fn mq_unlink
+system call
+will fail if:
+.Bl -tag -width Er
+.It Bq Er EACCESS
+Permission is denied to unlink the message queue represented by
+.Fa name .
+.It Bq Er EINVAL
+.Fa name
+is invalid.
+.It Bq Er ENAMETOOLONG
+The length of the
+.Fa name
+argument exceeds
+.Brq Dv PATH_MAX
+or
+a pathname component is longer than
+.Brq Dv NAME_MAX .
+.It Bq Er ENOENT
+The message queue does not exist.
+.It Bq Er ENOSYS
+.Xr mqueuefs 5
+module is neither loaded nor included in the kernel.
+.El
+.Sh SEE ALSO
+.Xr mq_open 2
+.Sh STANDARDS
+The
+.Fn mq_unlink
+system call conforms to
+.St -p1003.1-2004 .
+The
+.Bq Er EACCESS
+error code is an extension to the standard.
+.Sh HISTORY
+Support for POSIX message queues first appeared in
+.Fx 7.0 .
+.Sh COPYRIGHT
+Portions of this text are reprinted and reproduced in electronic form
+from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology --
+Portable Operating System Interface (POSIX), The Open Group Base
+Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of
+Electrical and Electronics Engineers, Inc and The Open Group.
+In the event of any discrepancy between this version and the original IEEE and
+The Open Group Standard, the original IEEE and The Open Group Standard is
+the referee document.
+The original Standard can be obtained online at
+http://www.opengroup.org/unix/online.html.