개요

• 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
• MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
• svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.

copyb(9f)

copyb(9F)                      Kernel Functions                      copyb(9F)



NAME
       copyb - copy a message block

SYNOPSIS
       #include <sys/stream.h>

       mblk_t *copyb(mblk_t *bp);

INTERFACE LEVEL
       Architecture independent level 1 (DDI/DKI).

PARAMETERS
       bp    Pointer to the message block from which data is copied.


DESCRIPTION
       The  copyb() function allocates a new message block, and copies into it
       the data from the block that bp denotes. The new block will be at least
       as  large as the block being copied. copyb() uses the b_rptr and b_wptr
       members of bp to determine how many bytes to copy.

RETURN VALUES
       If successful, copyb() returns a pointer to the newly allocated message
       block containing the copied data. Otherwise, it returns a NULL pointer.

CONTEXT
       The copyb() function can be called from user, interrupt, or kernel con‐
       text.

EXAMPLES
       Example 1 Using copyb



       For each message in the list, test to see if the  downstream  queue  is
       full with the canputnext(9F) function (line 21). If it is not full, use
       copyb to copy a header message block, and dupmsg(9F) to  duplicate  the
       data to be retransmitted. If either operation fails, reschedule a time‐
       out at the next valid interval.



       Update the new header block with the correct destination address  (line
       34),  link  the  message  to it (line 35), and send it downstream (line
       36). At the end of the list, reschedule this routine.


          1  struct retrans {
          2        mblk_t             *r_mp;
          3        int                r_address;
          4        queue_t            *r_outq;
          5        struct retrans     *r_next;
          6  };
          7
          8  struct protoheader {
                ...
          9     int                    h_address;
                ...
         10  };
         11
         12  mblk_t *header;
         13
         14  void
         15  retransmit(struct retrans *ret)
         16  {
         17       mblk_t *bp, *mp;
         18       struct protoheader *php;
         19
         20       while (ret) {
         21         if (!canputnext(ret->r_outq)) {   /* no room */
         22                ret = ret->r_next;
         23                continue;
         24         }
         25         bp = copyb(header);               /* copy header msg. block */
         26         if (bp == NULL)
         27               break;
         28         mp = dupmsg(ret->r_mp);           /* duplicate data */
         29         if (mp == NULL) {                 /* if unsuccessful */
         30              freeb(bp);                   /* free the block */
         31              break;
         32         }
         33         php = (struct protoheader *)bp->b_rptr;
         34         php->h_address = ret->r_address;   /* new header */
         35         bp->bp_cont = mp;                  /* link the message */
         36         putnext(ret->r_outq, bp);          /* send downstream */
         37         ret = ret->r_next;
         38       }
         39       /* reschedule */
         40       (void) timeout(retransmit, (caddr_t)ret, RETRANS_TIME);
         41  }



SEE ALSO
       allocb(9F), canputnext(9F), dupmsg(9F)


       Writing Device Drivers in Oracle Solaris 11.4


       STREAMS Programming Guide



Oracle Solaris 11.4               16 Jan 2006                        copyb(9F)