PACKET multi user printer :

INT VAR printer channel ;

  put ("Druckerkanal:") ;
  get (printer channel) ;
  server channel (printer channel); 
 
  command dialogue (FALSE) ;
  spool manager (PROC printer) ;


LET ack = 0 ,
    fetch code = 11 ,
    file type = 1003 ;

INT VAR reply , old heap size ;

DATASPACE VAR ds ;

FILE VAR file ;

PROC printer :

  disable stop ;
  continue (server channel) ;
  IF is error
    THEN clear error ;
         end
  FI ;

  old heap size := heap size ;
  REP
    forget (ds) ;
    execute print ;
    IF is error AND online
      THEN put error
    FI ;
    clear error ;
    IF heap size > old heap size + 4
      THEN collect heap garbage ;
           old heap size := heap size
    FI
  PER 

ENDPROC printer ;

PROC execute print :

  enable stop ;
  REP
    ds := nilspace ;
    call (father, fetch code, ds, reply) ;
    IF reply = ack CAND type (ds) = file type
      THEN print file
    FI ;
    forget (ds)
  PER .

print file :
  file := sequential file (input, ds) ;
  IF is elan source (file)
    THEN elan list (file)
    ELSE print (file)
  FI .

ENDPROC execute print ;

ENDPACKET multi user printer ;