Beefy Boxes and Bandwidth Generously Provided by pair Networks
Clear questions and runnable code
get the best and fastest answer
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??
Seek isn't really for skipping forwards into unknown territory like this unless you know enough about the file format to be able to know exactly where you want to go to. In particular, you can't do a "skip the next 100 files" command.

However, if you do a

push(@tells, $dir->tell());
at the start of each page, it will allow you to use seek later to skip back to any of those particular points later using the values stored in the @tells array. E.G.
# have now read through all files once and stored every # Nth position in @tells my $dirpos = @tells / 2; # start in the middle my $browsing = 1; while ($browsing) { my $action = ""; $f = $dir->seek($tells[$dirpos]); # code to go here to read next N files and display # results to user. # Come back here when we have an submit from the user # and $action set to the result. if ($action eq "pageforwards") { #should check for end $dirpos++; } elsif ($action eq "pagebackwards") { #should check for start $dirpos--; } else { # do other actions $browsing = 0; } }

This way, you only have to store a value for every Nth file, which is a big reduction in storage.

--
Brovnik.


In reply to Re: A story of a Perl Monk and Problem by Brovnik
in thread A story of a Perl Monk and Problem by lindex

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others meditating upon the Monastery: (8)
As of 2024-04-16 08:40 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found