Hi Monks, my first post here; I've been lurking for some time, ever since I became a perl coder. I ran across something interesting today in the behavior of seek on a tied filehandle that I could not find in any documention or discussion on this wonderful site. A little background: I wrote a tied filehandle module to return records of binary science data. The records are indexed by time, so my SEEK function naturally accepts a time value; a *floating-point* time value: since the data are accumulated on millisecond scales. But things were not right; the seeks went awry. Why?

Because 'seek' is a perl function that magically accesses my own SEEK subroutine, but which *always* coerces its second argument (the first is the fh) to an integer! Do you doubt this? See the code below!

(btw: I fixed my little problem by multiplying the times in the argument list by 1000 and then dividing by same within SEEK.)

- GRR 
#!/usr/bin/perl
use strict;
package myNull;

sub TIEHANDLE {
    my $class = shift;
    my $fh = local *FH;
    bless \$fh, $class;
}

sub SEEK {
    my $class = shift;
    my $offset = shift;
    my $whence = shift;
    print "SEEK: offset = $offset\n";
}
1;

perl -e 'use myNull; tie *null, "myNull"; seek null, 5.5, 0;'

SEEK: offset = 5

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In reply to Interesting SEEK behavior on tied filehandle by GammaRay Rob

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