ASMB
      HED S/P ISNUL        (15/10/75)   F. GAULLIER 
      NAM ISNUL,7 . 92903-16001 REV.1805  760907
* 
*     SOURCE 92903-18027
* 
      SPC 2 
**************************************************************
* (C) COPYRIGHT HEWLETT-PACKARD COMPANY 1978.  ALL RIGHTS    *
* RESERVED.  NO PART OF THIS PROGRAM MAY BE PHOTOCOPIED, RE- *
* PRODUCED, OR TRANSLATED TO ANOTHER PROGRAM LANGUAGE WITH-  *
* OUT THE PRIOR WRITTEN CONSENT OF HEWLETT-PACKARD COMPANY.  *
**************************************************************
      SPC 2 
      ENT ISNUL 
      EXT .ENTR 
   SPC 2
*      IF(ISNUL(IBUF,# OF WORDS) )   GARBAGE IN BUFFER
*      ONLY NUL CHARACTERS FOUND IN THE BUFFER
  SPC 1 
.B    NOP 
.N    NOP 
ISNUL NOP 
      JSB .ENTR 
      DEF .B
* 
      LDA .N,I
      CMA,INA 
      CCE,SSA,RSS 
      JMP ISNUL,I   OK !  --->  .FALSE.  E=1
      STA .N
      LDB .B
LOOP  LDA 1,I 
      INB 
      CCE,SZA 
      JMP NO
      ISZ .N
      JMP LOOP
      JMP ISNUL,I   OK !  --->  .FALSE. / 0  E=1
* 
NO    CCA,CLE       ERROR !  ---> .TRUE.  E=0 
      JMP ISNUL,I 
      END 
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