Current File : //usr/man/man9s/msgb.9s

'\" te
.\" Copyright (c) 2000, Sun Microsystems, Inc. All Rights Reserved.
.\" Copyright 1989 AT&T
.TH msgb 9S "11 Apr 1991" "SunOS 5.11" "Data Structures for Drivers"
.SH NAME
msgb, mblk \- STREAMS message block structure
.SH SYNOPSIS
.LP
.nf
#include <sys/stream.h> 
.fi

.SH INTERFACE LEVEL
.sp
.LP
Architecture independent level 1 (DDI/DKI)
.SH DESCRIPTION
.sp
.LP
A STREAMS message is made up of one or more message blocks, referenced by a pointer to a \fBmsgb\fR structure. The \fBb_next\fR and  \fBb_prev\fR pointers are used to link messages together on a \fBQUEUE\fR. The  \fBb_cont\fR pointer links message blocks together when a message consists of more than one block.
.sp
.LP
Each  \fBmsgb\fR structure also includes a pointer to a  \fBdatab\fR(9S) structure, the data block (which contains pointers to the actual data of the message), and the type of the message.
.SH STRUCTURE MEMBERS
.sp
.in +2
.nf
struct msgb     *b_next;    /* next message on queue */
struct msgb     *b_prev;    /* previous message on queue */
struct msgb     *b_cont;    /* next message block */
unsigned char   *b_rptr;    /* 1st unread data byte of buffer */
unsigned char   *b_wptr;    /* 1st unwritten data byte of buffer */
struct datab    *b_datap;   /* pointer to data block */
unsigned char   b_band;     /* message priority  */
unsigned short  b_flag;     /* used by stream head  */
.fi
.in -2

.sp
.LP
Valid flags are as follows:
.sp
.ne 2
.mk
.na
\fB\fBMSGMARK\fR \fR
.ad
.RS 13n
.rt  
Last byte of message is marked.
.RE

.sp
.ne 2
.mk
.na
\fB\fBMSGDELIM\fR \fR
.ad
.RS 13n
.rt  
Message is delimited.
.RE

.sp
.LP
The \fBmsgb\fR structure is defined as type \fBmblk_t\fR. 
.SH SEE ALSO
.sp
.LP
\fBdatab\fR(9S) 
.sp
.LP
\fIWriting Device Drivers for Oracle Solaris 11.2\fR 
.sp
.LP
\fISTREAMS Programming Guide\fR