pro rd_dmp,file,tstart,tend

on_error, 1             ; return to caller

if datatype(file) ne 'STR' then file=chklog('dmpfl1')
f=findfile(file,count=count)
if count eq 0 then begin
 message,'dump file not found',/contin
 fetch,file
 mklog,'dmpfl1',file
endif

;-- define buffers and variables

on_ioerror,exit
a = bytarr(4096)    
openr, lun,file, error=ierr, 4096,/get_lun
if ierr ne 0 then message, !err_string
rec = assoc (lun,bytarr(4096))
forever=0
i=-1
message,'scanning '+file+' ...',/contin
repeat begin
 i=i+1
 a=rec(i)
 prthdr, a,day,yr,msod,label=label,/quiet
 if (not label) and (n_elements(dstart) eq 0) then dstart=msod
endrep until forever

exit:on_ioerror,null
if (n_elements(dend) eq 0) then dend=msod

tstart=atime(dstart)
tend=atime(dend)

message,'start time of dump file --> '+tstart,/contin
message,'end   time of dump file --> '+tend,/contin

free_lun,lun & close,lun

return  &  end