Tribblix: manual page: unlinkb.9f

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

NAME

unlinkb - remove a message block from the head of a message

SYNOPSIS

#include <sys/stream.h>

mblk_t *unlinkb(mblk_t *mp);

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).

PARAMETERS

mp
Pointer to the message.

DESCRIPTION

The unlinkb() function removes the first message block from the
message pointed to by mp. A new message, minus the removed message
block, is returned.

RETURN VALUES

If successful, the unlinkb() function returns a pointer to the
message with the first message block removed. If there is only one
message block in the message, NULL is returned.

CONTEXT

The unlinkb() function can be called from user, interrupt, or kernel
context.

EXAMPLES

Example 1 unlinkb() example

The routine expects to get passed an M_PROTO T_DATA_IND message. It
will remove and free the M_PROTO header and return the remaining
M_DATA portion of the message.

1 mblk_t *
2 makedata(mp)
3 mblk_t *mp;
4 {
5 mblk_t *nmp;
6
7 nmp = unlinkb(mp);
8 freeb(mp);
9 return(nmp);
10 }