OpenEuphoria

Re: memory

• Posted by martin.stachon at worldonline.cz Jul 14, 2001
• 405 views

Kat writes:
> > Kat writes :
> > > Hey all,,
> > >
> > > I have a short program that opens a 6.8megabyte file, containing text
> > > separated by lots of {0}. The object is to eliminate the {zero}s, and
> > reformat
> > > the results to a more text-looking file. What i can't figure is that
> > Taskinfo
> > > says Eu is using 86Megabytes in memory to do it!
> > >
> > > Are these the lines doing it? Is a new instance of data created every
time
> > it
> > > is mentioned in the line?:
> > >
> > > puts(1,"removing 10 nulls\n")
> > > place = match({0,0,0,0,0,0,0,0,0,0},data)
> > > while place do
> > >  data = data[1..place] & data[place+10..length(data)]
> > >  place = match({0,0,0,0,0,0,0,0,0,0},data)
> > > end while
> > >
> > >
> > > Kat
> > >
> >
> > Hello Kat,
> >
> > Wouldn't be a better way to do the job this code?:
> >
> > include file.e
> > include get.e
> > integer fn
> > fn = open("file.txt","rb")
> > integer char
> > sequence result
> > result = {}
> > while 1 do
> >     char = getc(fn)
> >     if char = -1 then exit -- EOF
> >     eslif char = 0  then -- ignore
> >     else result &= char -- append to the result
> >     end if
> > end while
> > close(fn)
>
> That way makes 6.8 million file accesses. Eventually, i went to pruning a
> little off the front of data in a loop, and processing 50 bytes at a time.
The
> program eventually was using 120megs of ram and was thrashing the
> harddrive for 6 hours, so i killed it off.
>
> I'd still like to know why it wanted so much memory for a little 6.8meg
text
> file.
>
> Kat

No, Euphoria doesn't read by 1 byte with getc(). It uses buffer.
(See docs)

Martin