Something like this should do it. See the docs and/or ask for anything you do not understand.

#! perl -slw use strict; my @grid; open my $fh, '<:raw', 'the file' or die $!; while( 1 ) { my( $recSize, $dummy, $record ); sysread( $fh, $recSize, 4 ) or last; $recSize = unpack 'N', $recSize; ##(*) sysread( $fh, $record, $recSize ) == $recSize or die "truncated record"; sysread( $fh, $dummy, 4 ) == 4 and unpack( 'N', $dummy ) == $recSize ##(*) or die "missing or invalid trailer"; ## (*) You may need V depending upon which platform your file was +created on push @grid, [ unpack 'N*', $record ]; } close $fh; ## @grid should now contain your data ## Addressable in the usual $grid[ X ][ Y ] manner. ## Though it might be $array[ Y ][ X ] ## I forget which order FORTRAN writes arrays in?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: reading binary files with Perl by BrowserUk
in thread reading binary files with Perl by jpk1292000

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

  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.