open a file in Perl

open my $fh, '<:encoding(utf8)', $filename or die "Could not open '$filename' $!"

Open for writing:

open my $fh, '>:encoding(utf8)', $filename or die "Could not open '$filename' $!"

Open to append:

open my $fh, '>>:encoding(utf8)', $filename or die "Could not open '$filename' $!"

• Open and read from file
• Always use 3-argument open
• Never the old way