4.3BSD - /usr/ingres/source/ctlmod/pb_prime.c

   1: # include   "ctlmod.h"
   2: # include   "pipes.h"
   3: # include   <sccs.h>
   4: 
   5: SCCSID(@(#)pb_prime.c	8.1	12/31/84)
   6: 
   7: /*
   8: **  PB_PRIME -- prime a pipe for reading or writing
   9: **
  10: **	This clears out any nasty stuff in the pipe block.  If
  11: **	we are reading, it reads the first block so that we can
  12: **	know what sort it is.
  13: **
  14: **	Parameters:
  15: **		ppb -- a pointer to the pipe block.
  16: **		type -- if PB_NOTYPE, we are setting for reading.
  17: **			Otherwise, we are setting to write a
  18: **			message of the indicated type.
  19: **
  20: **	Returns:
  21: **		none
  22: **
  23: **	Side Effects:
  24: **		Changes *ppb.
  25: **
  26: **	Trace Flags:
  27: **		12.0
  28: */
  29: 
  30: pb_prime(ppb, type)
  31: register pb_t   *ppb;
  32: int     type;
  33: {
  34: # ifdef xCTR2
  35:     if (tTf(12, 0))
  36:         lprintf("pb_prime: type %d\n", type);
  37: # endif
  38:     if (type == PB_NOTYPE)
  39:     {
  40:         /* read pipe prime -- get the first block */
  41:         pb_read(ppb);
  42:     }
  43:     else
  44:     {
  45:         /* write pipe prime -- set up initial pointers */
  46:         ppb->pb_from = Cm.cm_myproc;
  47:         ppb->pb_type = type;
  48:         ppb->pb_stat = 0;
  49:         ppb->pb_nleft = PB_DBSIZE;
  50:         ppb->pb_nused = 0;
  51:     }
  52: 
  53:     /* do common initialization */
  54:     ppb->pb_xptr = ppb->pb_data;
  55: }

Defined functions