Path: utzoo!utgpu!water!watmath!clyde!att!att-ih!ihnp4!ucbvax!CLVMS.CLARKSON.EDU!ABSTINE
From: ABSTINE@CLVMS.CLARKSON.EDU (Art Stine - Network Engineer)
Newsgroups: comp.os.vms
Subject: anyone have any clues why this doesn't work
Message-ID: <8804260836.AA24421@ucbvax.Berkeley.EDU>
Date: 20 Apr 88 22:14:00 GMT
Sender: usenet@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 80


     
Folks:
        I am trying to whip up a quick and dirty program which will
        emulate the Unix tail program, ie, read the last n lines of
        a file. I wrote up the following code, which seems like it
        should work, but it doesn't seem to position the file at EOF.
        any clues what i'm doing wrong?
     
        thanks
     
art stine
network engineer
clarkson u
     
     
     
        character*80 inline
        external open_eof
        integer*4 for_len
        open(1, name='SYS$MANAGER:LPR_SERVER.LOG', type='OLD',
     &          useropen=open_eof)
     
        print 100
100     format('$Number of records from end? ')
        accept*,nback
        read(1,'(a)', end=5) inline
5       do i = 1, nback
                backspace 1
        enddo
10      read(1,'(a)', end=99) inline
        print *, inline
        goto 10
     
99      close(unit=1)
        call exit
        end
     
     
     
        INTEGER FUNCTION open_eof(fab, rab, lun)
        IMPLICIT NONE
!
! Include definition files
!
        INCLUDE '($SYSSRVNAM)'
        INCLUDE '($FABDEF)'
        INCLUDE '($RABDEF)'
!
! Parameter declarations
!
        RECORD /FABDEF/ fab
        RECORD /RABDEF/ rab
        INTEGER*4 lun
!
! Local storage
!
        INTEGER*4 status
     
     
!
! open file
!
        status = sys$open(fab)
!
! if opened ok, then connect stream to file
!
     
        IF (status) THEN
!
! set open at EOF flag
!
        rab.rab$l_rop = rab.rab$l_rop .OR. rab$m_eof
        status = sys$connect(rab)
     
        ENDIF
     
        open_eof = status
        return
        end