07-19-2005
Err well, typically you would identify a line by the presence of the '\n' character.
So, open the file. Go the end of the file. Work backwards towards the start of the file, counting the number of '\n'. When you have reached the required number of '\n' characters, store the position in the file.
Read from the stored position of the file to the end of file into memory buffer. Dump buffer contents into file.
Or something like that ...
Some useful functions are fopen, fclose, fread and fwrite.
Hope this helps.
MBB
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LEARN ABOUT DEBIAN
http::proxy::bodyfilter::lines
HTTP::Proxy::BodyFilter::lines(3pm) User Contributed Perl Documentation HTTP::Proxy::BodyFilter::lines(3pm)
NAME
HTTP::Proxy::BodyFilter::lines - A filter that outputs only complete lines
SYNOPSIS
use HTTP::Proxy::BodyFilter::lines;
use MyFilter; # this filter only works on complete lines
my $filter = MyFilter->new();
# stack both filters so that they'll handle text/* responses
$proxy->push_filter(
mime => 'text/*',
response => HTTP::Proxy::BodyFilter::lines->new,
response => $filter
);
# I want my lines to end with '!'
# This is equivalent to $/ = '!' in a normal Perl program
my $lines = HTTP::Proxy::BodyFilter::lines->new('!');
DESCRIPTION
The HTTP::Proxy::BodyFilter::lines filter makes sure that the next filter in the filter chain will only receive complete lines. The
"chunks" of data received by the following filters with either end with "
" or will be the last piece of data for the current HTTP message
body.
You can change the idea the filter has of what is a line by passing to its constructor the string it should understand as line ending. "
"
is the default value.
my $filter = HTTP::Proxy::BodyFilter::lines->new( $sep );
This is similar to modifying $/ in a Perl program. In fact, this filter has a behaviour so similar to modifying $/ that it also knows about
"paragraph mode" and "record mode".
Note that the "slurp" mode is not supported. Please use HTTP::Proxy::BodyFilter::complete to enable the generic store and forward filter
mechanism.
METHODS
This filter defines the following methods, which are automatically called:
init()
Initialise the filter with the EOL information.
filter()
Keeps unfinished lines for later.
will_modify()
This method returns a false value, thus indicating to the system that it will not modify data passing through.
SEE ALSO
HTTP::Proxy, HTTP::Proxy::BodyFilter.
AUTHOR
Philippe "BooK" Bruhat, <book@cpan.org>.
COPYRIGHT
Copyright 2003-2006, Philippe Bruhat.
LICENSE
This module is free software; you can redistribute it or modify it under the same terms as Perl itself.
perl v5.12.4 2011-07-03 HTTP::Proxy::BodyFilter::lines(3pm)