1. get.e
Matt Lewis wrote:
>
> don cole wrote:
> >
> > What I want to achieve is to read the whole file in one fell swoop.
> >
> > If I use gets() all the way through it works but takes longer.
>
> gets() is probably the fasted way to read it. get() is wholly inappropriate.
> As the docs state, it's for reading euphoria objects that have been
> printed using print (though is also handles things like double and single
> quotes). You don't say how you plan to store the data, but I'll assume you
> just want the lines concatenated:
>
> }}}
<eucode>
> object in
> sequence s
> s = {}
> in = gets(fin)
> while( sequence( in ) ) do
> s &= in
> in = gets( fin )
> end while
> </eucode>
{{{
> I use this basic pattern all the time for reading files (though I usually
> keep each line in it's own sequence), and I've never had a problem with the
>
> speed. I recall one point in the past when people tried using things like
> get_bytes to speed up file IO, but didn't. It seems that the actual
> hardware IO is the bottleneck.
>
> Matt
> }}}
<eucode>
object in
sequence s
integer fin
fin=open("myfile.ew","r")
s = {}
in = gets(fin)
while( sequence( in ) ) do
s &= in
in = gets( fin )
end while
</eucode>
{{{
Is what I'm using and you're saying that's faster than anything using get()?
Don Cole
2. Re: get.e
For what its worth, here is the routine I use to red an entire file into a
sequence...
global function ReadFile(sequence pFileName)
integer lFH
sequence lData
lFH = open(pFileName,"rb")
if lFH = -1 then
return -1
end if
machine_proc(19, {lFH,-1})
lData = repeat(0, machine_func(20, lFH))
machine_proc(19, {lFH,0})
for i = 1 to length(lData) do
lData[i] = getc(lFH)
end for
close(lFH)
return lData
end function
Note that machine routine 19 is 'seek' and 20 is 'where'. I did it this way to
avoid the tiny overhead of including file.e and using it's routine.
On my machine this reads a 64 Meg file in around 1.4 seconds.
--
Derek Parnell
Melbourne, Australia
Skype name: derek.j.parnell
3. Re: get.e
- Posted by don cole <doncole at pacbell?net>
Jul 07, 2007
-
Last edited Jul 08, 2007
Derek Parnell wrote:
>
> For what its worth, here is the routine I use to red an entire file into a
> sequence...
> }}}
<eucode>
> global function ReadFile(sequence pFileName)
> integer lFH
> sequence lData
>
> lFH = open(pFileName,"rb")
> if lFH = -1 then
> return -1
> end if
>
> machine_proc(19, {lFH,-1})
> lData = repeat(0, machine_func(20, lFH))
> machine_proc(19, {lFH,0})
>
> for i = 1 to length(lData) do
> lData[i] = getc(lFH)
> end for
> close(lFH)
>
> return lData
> end function
> </eucode>
{{{
>
>
> Note that machine routine 19 is 'seek' and 20 is 'where'. I did it this way
> to avoid the tiny overhead of including file.e and using it's routine.
>
> On my machine this reads a 64 Meg file in around 1.4 seconds.
>
> --
> Derek Parnell
> Melbourne, Australia
> Skype name: derek.j.parnell
Thanks Derek,
Don Cole
