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( [id://3333]=superdoc: print w/replies, xml ) Need Help??
What have I done wrong?

The index is zero based, so if you want to treat the first line in the file as 1st rather than 0th, you need to substract 1 from the number before looking it up in the index:

open INDEX, "<:raw","$index" or die "Can't open $index for reading: $! +"; my $len = -s( INDEX ); sysread INDEX, my( $idx ), $len; close INDEX; open FILE, "<$oneper" or die "Can't open $oneper for reading: $!"; foreach my $lineNum (sort {$a cmp $b} keys %todo) { my $offset = unpack 'N', substr $idx, ( $lineNum - 1 ) * 4, 4; ## + Modified!! print "offset is $offset for linenum $lineNum\n<br>"; seek FILE, $offset, 0; my $line = <FILE>; print "found line $line\n"; }

That should do the trick.


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The start of some sanity?


In reply to Re^3: Index a file with pack for fast access by BrowserUk
in thread Index a file with pack for fast access by Ineffectual

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