'\" te
.\" Copyright (c) 2006, Sun Microsystems, Inc. All Rights Reserved.
.\" Copyright 1989 AT&T
.TH rmvb 9F "16 Jan 2006" "SunOS 5.11" "Kernel Functions for Drivers"
.SH NAME
rmvb \- remove a message block from a message
.SH SYNOPSIS
.LP
.nf
#include <sys/stream.h>

\fBmblk_t *\fR\fBrmvb\fR(\fBmblk_t *\fR\fImp\fR, \fBmblk_t *\fR\fIbp\fR);
.fi

.SH INTERFACE LEVEL
.sp
.LP
Architecture independent level 1 (DDI/DKI).
.SH PARAMETERS
.sp
.ne 2
.mk
.na
\fB\fImp\fR\fR
.ad
.RS 6n
.rt  
Message from which a block is to be removed. \fBmblk_t\fR is an instance of the \fBmsgb\fR(9S) structure.
.RE

.sp
.ne 2
.mk
.na
\fB\fIbp\fR\fR
.ad
.RS 6n
.rt  
Message block to be removed.
.RE

.SH DESCRIPTION
.sp
.LP
The \fBrmvb()\fR function removes a message block (\fIbp\fR) from a message (\fImp\fR), and returns a pointer to the altered message. The message block is not freed, merely removed from the message. It is the module or driver's responsibility to free the message block.
.SH RETURN VALUES
.sp
.LP
If successful, a pointer to the message (minus the removed block) is returned. The pointer is \fBNULL\fR if \fIbp\fR was the only block of the message before  \fBrmvb()\fR was called. If the designated message block (\fIbp\fR) does not exist, \fB-1\fR is returned.
.SH CONTEXT
.sp
.LP
The \fBrmvb()\fR function can be called from user, interrupt, or kernel context.
.SH EXAMPLES
.sp
.LP
This routine removes all zero-length \fBM_DATA\fR message blocks from the given message. For each message block in the message, save the next message block (line 10). If the current message block is of type \fBM_DATA\fR and has no data in its buffer (line 11), then remove it from the message (line 12) and free it (line 13). In either case, continue with the next message block in the message (line 16).
.sp
.in +2
.nf
1  void
 2  xxclean(mp)
 3      mblk_t *mp;
 4  {
 5	       mblk_t *tmp;
 6	       mblk_t *nmp;
 7
 8	       tmp = mp;
 9	       while (tmp) {
10		           nmp = tmp->b_cont;
11		           if ((tmp->b_datap->db_type == M_DATA) &&
		                 (tmp->b_rptr == tmp->b_wptr)) {
12			           (void) rmvb(mp, tmp);
13			           freeb(tmp);
14		           }
15		           tmp = nmp;
16	       }
17  }
.fi
.in -2

.SH SEE ALSO
.sp
.LP
\fBfreeb\fR(9F), \fBmsgb\fR(9S)
.sp
.LP
\fIWriting Device Drivers for Oracle Solaris 11.2\fR
.sp
.LP
\fISTREAMS Programming Guide\fR