Erm, you are aware that using just <> does pretty much the same thing already?

Yes, that's right, but in this particular script I use my filehandles in a closure:

sub get_closure {
  my ($filename) = @_;
  open my $ifh, "<", $filename or die $!;
  return sub {
      # subroutine that returns one record per call
  }
}

# and then:

my $getNextRecord = get_closure($filename);
while ( my $record = $getNextRecord->() ){
    # do something with $record
}

[download]

Yes, I know that this sounds paranoic, but I find some benefits using this (private filehandles, a bit of encapsulation, access to $ifh a bit faster, etc...

Given this scenario I don't know if using <> is easy or even possible.

Not to mention that while( <$ifh> ) { ... } isn't going to return false until there's an EOF condition on STDIN in which case you're not really going to gain much by not closing it (at least nothing useful that I can think of off hand).

Sure, I agree, but you can have something like this: 

my $file = shift @ARGV;

my $ifh;
my $is_stdin = 0;
if (defined $file){
  open $ifh, "<", $file or die $!;
} else {
  $ifh = *STDIN;
  $is_stdin++;
}

while (<$ifh>){
   # Process
}
#close $ifh unless $is_stdin;
close $ifh;

## code passes...
## ... and
my $another_value = <STDIN>;

[download]

If you happen to close STDIN, that last statement would give you an error.

Ok, I will stop here, or you will think that I'm really a paranoic :-)

citromatik

In reply to Re^2: input from STDIN or from a file by citromatik
in thread input from STDIN or from a file by citromatik

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