2.11BSD#431 - /usr/ingres/source/equel/runtime/IIresync.c

   1: # include   "../../pipes.h"
   2: # include   "../../ingres.h"
   3: # include   "IIglobals.h"
   4: 
   5: /*
   6: **  RESYNCHRONIZE PIPES AFTER AN INTERRUPT
   7: **
   8: **	The pipes are all cleared out.  This routines must be called
   9: **	by all processes in the system simultaneously.  It should be
  10: **	called from the interrupt catching routine.
  11: **
  12: **	History:
  13: **		11/2/79 -- (marc) added IIeinpipe PRIME to get rid
  14: **			of old data from the pipe which was being read
  15: **			in the retrieve after the interrupt.
  16: */
  17: 
  18: extern  exit();
  19: int (*IIinterrupt)()    = &exit;
  20: IIresync()
  21: {
  22:     struct pipfrmt      buf;
  23:     register struct pipfrmt *pbuf;
  24:     extern struct pipfrmt   IIeinpipe;
  25: 
  26:     signal(2,1);
  27:     pbuf = &buf;
  28:     IIwrpipe(P_PRIME, pbuf, 0, 0, 0);
  29:     /* write the sync block out */
  30:     IIwrpipe(P_INT, pbuf, IIw_down);
  31: 
  32:     /* read the sync block back on both pipes */
  33:     /* must be in right order */
  34:     IIrdpipe(P_INT, pbuf, IIr_front);
  35:     IIrdpipe(P_INT, pbuf, IIr_down);
  36: 
  37:     /* flush remaining old data from buffer */
  38:     IIrdpipe(P_PRIME, &IIeinpipe, 0, 0, 0);
  39: 
  40:     /* Get out of a retrieve and clear errors */
  41:     IIin_retrieve = 0;
  42:     IIerrflag = 0;
  43:     IIndomains = IIdomains = 0;
  44: 
  45: 
  46:     /* reset the signal */
  47:     signal(2,&IIresync);
  48:     /* allow the user to service the interrupt */
  49:     (*IIinterrupt)(-1);
  50:     /*
  51: 	** If IIinterupt returns the user might hang in a retrieve
  52: 	*/
  53: 
  54:     IIsyserr("Interupt returned");
  55: }

Defined functions