in reply to need nextline() sub

If I read what you wrote correctly, you want to pass a filename to a sub in another module and then later, be able to read the file one line at a time, right? If so, I think this might work:

package Foo;
use strict;

my $sep;

sub set_file {
    my $file = shift;
    $sep = shift || "\n";
    open FH, "< $file" or die "Cannot open $file for reading: $!";
}

sub get_line {
    local $/ = $sep;
    my $temp = <FH>;
    return $temp;
}

1;

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In your main program:

use strict;
use Foo;

Foo::set_file( $some_file );

for ( 0..10 ) {
    print Foo::get_line 
};

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If that's not what you're looking for, let us know. It seems to me that seek is not what you're needing here.

Cheers,
Ovid

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Re: (Ovid) Re: need nextline() sub
by mutagen (Novice) on Nov 22, 2001 at 06:04 UTC
    Zaxo was on the money with readline() - all i needed was to get underneath the abstraction of the <FH> operator. 
    package FileClerk;

open (FH,$file);

sub next_line {
  return (readline(*FH));
}

    [download]
    calling program: 
    use FileClerk;
for (FileClerk::next_line()) {
    print "$_\n";
}

    [download]
    The calling program doesn't need to care about the filehandle, which was my aim. Thanks everyone.
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      Zaxo was on the money with readline() - all i needed was to get underneath the abstraction of the <FH> operator.

      The spaceship operator (<>) is just a wrap around the readline function. You can get the same behaviour like this: 

      sub next_line {
  return scalar <FH>;
}

      [download]

      Another remark, it might be worth setting $/ before using readline. That way you don't get unexpected behaviour if someone fiddled with it. So put something like this at the start of your sub: 

        local $/ = "\n";

      [download]

      -- Hofmator

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