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.\" Common Development and Distribution License ("CDDL"), version 1.0.
.\" You may only use this file in accordance with the terms of version
.\" 1.0 of the CDDL.
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.\" Copyright 2014 Garrett D'Amore <garrett@damore.org>
.\"
.Dd "Dec 15, 2014"
.Dt CANPUTNEXT 9F
.Os
.Sh NAME
.Nm canputnext ,
.Nm bcanputnext
.Nd test for room in next message queue
.Sh SYNOPSIS
.In sys/stream.h
.
.Ft int
.Fo canputnext
.Fa "queue_t *q"
.Fc
.
.Ft int
.Fo bcanputnext
.Fa "queue_t *q"
.Fa "unsigned char pri"
.Fc
.
.Sh DESCRIPTION
The
.Fn canputnext
and
.Fn bcanputnext
functions atomically test for available space in the next
linked queue or priority band.
They are preferable to and safer than calling
.Xr canput 9F
and
.Xr bcanput 9F
directly on the the queue linked to by
.Fa q Ns No -> Ns Fa q_next .
.Lp
Drivers and modules should call these routines to ensure that room
on the next queue exists before calling
.Xr putnext 9F .
.Sh INTERFACE LEVEL
Architecture independent (DDI/DDK).
.Sh PARAMETERS
.Bl -tag -width Ds
.It Fa q
STREAMS queue.
.It Fa pri
Priority band to test.
.El
.Sh CONTEXT
These functions may be called in user, kernel, or interrupt
context.
.Sh RETURN VALUES
.Bl -tag -width Ds
.It 1
If the next message queue is not full.
.It 0
If the next message queue is full.
.El
.Sh SEE ALSO
.Rs
.%B "STREAMS Programming Guide"
.Re
.Rs
.%B "Writing Device Drivers"
.Re
.Pp
.Xr bcanput 9F ,
.Xr canput 9F ,
.Xr putnext 9F ,