Reading files backwards

[MisterX]

Then it's a simple case of

get last line of url thisurl
get last line of it

(can be written in 1 line)

--

Problem with "get url thisurl" is that the whole file will be read...

Doing this even on a 10 minute schedule (it's what I do), on a file of 3 to
20 MBs (even just 3) is going to be memory intensive... not every
efficient... On a fast network, it's ok... but on a cloggued or laggy net
connection... you're going to pull your hair out!

Consulting the read file documentation revealed that you can read at an
offset for a given length. So, you'll have to get the detailed file
information of folder above the file, filter your file, read the size,
calculate your buffer size, open file, read at offset
filelengthminusbuffersize for buffer size, close file... I might want to
make smaller day.log files instead and join those at night to an archive
file/folder... in case you care to know what solution i chose...

i WONT try the negative offset ;( since I presume it will crash MC as did
the last command. Though knowing MC, it probably wont crash and wont work
nonetheless ;). MCv2.4.3 will not crash and will read that last <object>
without resorting to reading the whole file we'll hope!

Thanks for the tip it will come in handy if i use the day.log style log!!!
cheers
Xavier

> -----Original Message-----
> From: metacard-admin at lists.runrev.com
> [mailto:metacard-admin at lists.runrev.com]On Behalf Of shop
> Sent: Monday, April 22, 2002 15:27
> To: metacard at lists.runrev.com
> Subject: Re: Reading files backwards
>
>
> I have found that referring to files as URLs is a beautiful thing
> because it
> allows you to refer to a file as if it were a variable which means you can
> use all your chunk expressions on it.  Sooo, try
>
> put the last line of url "file:blabla.txt" into r
>
> The only exception I've found to my opening statement is that
> delete doesn't
> seem to work with URLs.  I.E. delete the last line of url
> "file:blabla.txt"
> returns an error.
>
> Rich
> Payne Sparkman Mfg.
> shop at paynesparkman.com
>
> ----- Original Message -----
> From: <xbury.cs at clearstream.com>
> To: <metacard at lists.runrev.com>
> Sent: Monday, April 22, 2002 7:54 AM
> Subject: Reading files backwards
>
>
> > Hi Gang,
> >
> > Got a problem which may help others if there is a solution...
> > I need to read the very last line from a file that's 3 - 20MBs large...
> > So I tried:
> >
> > open file blabla for reading
> > read from file blabla for -100
> > put the result into r
> > put it into x
> > close file blabla
> >
> > Unfortunately I never got an answer back, MC crashed...
> > No result, no error...
> >
> > I dont want to resort to external programs (tail.exe) to do this...
> > Does anyone have a standard scripted solution?
> >
> > Thanks in advance
> > Xavier
> >
> >
> >
> > Visit us at http://www.clearstream.com/_focus1.htm
> >
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