rmvb(D3)rmvb(D3)NAMErmvb - remove a message block from a message
SYNOPSIS
#include <sys/stream.h>
#include <sys/ddi.h>
mblk_t *rmvb(mblk_t *mp, mblk_t *bp);
Arguments
mp Pointer to the message from which a message block is to be
removed.
bp Pointer to the message block to be removed.
DESCRIPTIONrmvb removes the message block specified by bp from the message specified
mp and returns a pointer to the altered message.
Return Values
On success, a pointer to the message (minus the removed block) is
returned. If bp was the only block in the message before rmvb was
called, NULL is returned. If the designated message block (bp) was not
in the message, -1 is returned.
USAGE
The message block is not freed, merely removed from the message. It is
the caller's responsibility to free the message block.
Level
Base or Interrupt.
Synchronization Constraints
Does not sleep.
Driver-defined basic locks, read/write locks, and sleep locks may be held
across calls to this function.
Examples
This routine removes all zero-length M_DATA message blocks from the given
message. For each message block in the message, we save the next message
block (line 9). If the current message block is of type M_DATA and has
no data in its buffer (lines 10-11), then we remove the message block
from the message (line 12) and free it (line 13). In either case, we
continue with the next message block (line 15), until we have checked
every message block in the message.
1 void
2 xxclean(mp)
3 mblk_t *mp;
4 {
5 mblk_t *tmp;
6 mblk_t *nmp;
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rmvb(D3)rmvb(D3)
7 tmp = mp;
8 while (tmp) {
9 nmp = tmp->b_next;
10 if ((tmp->b_datap->db_type == M_DATA) &&
11 (tmp->b_rptr == tmp->b_wptr)) {
12 mp = rmvb(mp, tmp);
13 freeb(tmp);
14 }
15 tmp = nmp;
16 }
17 }
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