bsd man page for putnextctl1

putnextctl1(9F) 					   Kernel Functions for Drivers 					   putnextctl1(9F)

NAME

       putnextctl1 - send a control message with a one-byte parameter to a queue

SYNOPSIS

       #include <sys/stream.h>

       int putnextctl1(queue_t *q, int type, int p);

INTERFACE LEVEL

       Architecture independent level 1 (DDI/DKI).

PARAMETERS

       q	Queue to which the message is to be sent.

       type	Type of message.

       p	One-byte parameter.

DESCRIPTION

       putnextctl1(),  like  putctl1(9F), tests the type argument to make sure a data type has not been specified, and attempts to allocate a mes-
       sage block. The	p parameter can be used, for example, to specify how long the delay will be when an  M_DELAY message is being  sent.  put-
       nextctl1()  fails  if   type  is   M_DATA, M_PROTO, or  M_PCPROTO, or if a message block cannot be allocated. If successful,  putnextctl1()
       calls the  put(9E) routine of the queue pointed to by  q with the newly allocated and initialized message.

       A call to putnextctl1(q,type, p) is an atomic equivalent of putctl1(q->q_next, type, p). The STREAMS  framework	provides  whatever  mutual
       exclusion  is necessary to insure that dereferencing q through its q_next field and then invoking putctl1(9F) proceeds without interference
       from other threads.

       putnextctl1() should always be used in preference to putctl1(9F)

RETURN VALUES

       On success,  1 is returned.  0 is returned if  type is a data type, or if a message block cannot be allocated.

CONTEXT

       putnextctl1() can be called from user or interrupt context.

EXAMPLES

       See the	putnextctl(9F) function page for an example of putnextctl1().

SEE ALSO

       put(9E), allocb(9F), datamsg(9F), putctl1(9F), putnextctl(9F)

       Writing Device Drivers

	STREAMS Programming Guide

SunOS 5.10							    29 Mar 1993 						   putnextctl1(9F)