;***************************************************************
; CLRBRK - Clear a random file to ]'s.
;
; Dave Heyliger's CLRAND modified by S.Chirico.
; It ini's with ] instead of 0. Caution, don't have to be in opr:
; acct, and prgm does not ask for confirmation (tho you can just
; uncomment the proper lines, to take those dangerous things out).
;
; will work from ANY acct, so caution !
; Does NOT ask for confirmation !
;
; Usage: CLRBRK {filespec}
;
; Purpose: after you use CREATE , this will fill the entire file
; with ]
;***********************************************************************
SEARCH SYS
SEARCH SYSSYM
SEARCH TRM
; PHDR -1,0,PH$REE!PH$REU!PH$OPR ;must be in OPR:
.OFINI
.OFDEF IDDB,D.DDB ;DDB for the file
.OFSIZ IMPSIZ
;get the inpure space
GETIMP IMPSIZ,A3 ;A3 points to varibles
;process input line
BYP ;bypass bs
LIN ;just a CR?
BNE 10$ ;nope
TYPECR <Usage: CLRAND {filespec}, where filespec is a random file.>
TYPECR < (default extension is .DAT)>
EXIT
;set up DDB and use input as filename to see if valid
10$: LEA A1,IDDB(A3) ;point to a DDB
MOVB #D$ERC!D$BYP,IDDB+D.FLG(A3) ;set D$ERC bit (trap errors)
FSPEC @A1,DAT ;get the filename
CMPB IDDB+D.ERR(A3),#D$ESPC ;error?
BEQ INERR ;yup
CMP IDDB+D.FIL(A3),#0 ;just a ".xxx"?
BNE INOK ;nope, ok so far
INERR: TYPECR <?Invalid file specification>
EXIT
;looks good, see if random file
INOK: LEA A1,IDDB(A3) ;point to DDB
INIT @A1 ;initialize
LOOKUP @A1 ;find the file
BNE NOFILE ;nope - error
CMPW IDDB+D.WRK+6(A3),#-1 ;random file?
JEQ AOK ;yup, continue
LEA A2,IDDB+D.FIL(A3) ;nope, point to file
TYPE <?>
PFILE @A1 ;type out file
TYPECR < is not a random file.> ;and error message
EXIT ;then quit
NOFILE: TYPECR <?This file does not exist.>
EXIT
;double check the users intentions
AOK:
; CRLF
; TYPE <You are about to zero out all data in this file. Enter Y to confirm: >
; KBD
; CTRLC END ;quit on ^C
; CMPB @A2,#'Y ;yes?
; JNE END ;nope
;now get the number of blocks and clear each one
MOV IDDB+D.WRK(A3),D2 ;D2 holds the number of blocks
OPENR @A1 ;open the file
READIT: READ @A1 ;get a block
LOOP: MOV #128.,D3 ;number of longword clears
MOV IDDB+D.BUF(A3),A4 ;A4 points to block
10$: MOVB #'],(A4)+
MOVB #'],(A4)+
MOVB #'],(A4)+
MOVB #'],(A4)+
; CLR (A4)+ ;zero it out
DEC D3 ;one less to do
BNE 10$ ;still more to do
WRITE @A1 ;write the block
DEC D2 ;one less block to do
BEQ END ;if zero, we are done
INCW IDDB+D.REC+2(A3) ;point to next block
BR READIT ;and read it
