You are going to need the pass the file name to the get_statistics subroutine when you call it, which means you probably are going to need to save it in a globally accessible variable. You really should also be checking for definedness / existence of the file and success on open too. Also good practice to use lexical file handles and 3 argument opens. (Not critical but they can help avoid subtle bugs.)

my $current_file;

[download]
$mw-> Button (-text =>'Get Statistics', -command =>\&get_statistics($current_file));
## Fixed as pointed out by Eliya++ below. 
$mw-> Button (-text =>'Get Statistics', -command => sub{ get_statistic
+s($current_file)});



sub open_file { 
    my $open = $mw->getOpenFile(
        -filetypes => $types_OPEN,
        -defaultextension => '.sff'
    );
    if (defined $open and -e $open){ 
        $te->Load( "$open");
        $current_file = $open;
}

sub get_statistics {

   # blah blah 

   my $fastaFile = shift;
   unless (defined $fastaFile){
        warn "No file name supplied.\n";
        return;
   }
   open my $FASTA, '<', $fastaFile or warn "Couldn't open file: $!\n";

   # blah blah

   while (<$FASTA>) {

   # blah blah

[download]
};

In reply to Re^3: Perl tk - How to integrate external scripts by thundergnat
in thread Perl tk - How to integrate external scripts by Giorgio C

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