讀取檔名

Perl 不會嘗試解碼內建函式或模組返回的檔名。表示檔名的此類字串應始終顯式解碼，以便 Perl 將它們識別為 Unicode。

use v5.14;
use Encode qw(decode_utf8);

# Ensure that possible error messages printed to screen are converted to UTF-8.
# For this to work: Check that you terminal emulator is using UTF-8.
binmode STDOUT, ':utf8';
binmode STDERR, ':utf8';

# Example1  -- using readdir()
my $dir = '.';
opendir(my $dh, $dir) or die "Could not open directory '$dir': $!";
while (my $filename = decode_utf8(readdir $dh)) {
    # Do something with $filename
}
close $dh;

# Example2  -- using getcwd()
use Cwd qw(getcwd);
my $dir = decode_utf8( getcwd() );

# Example3  -- using abs2rel()
use File::Spec;
use utf8;
my $base = 'ø';
my $path = "$base/b/æ";
my $relpath = decode_utf8( File::Spec->abs2rel( $path, $base ) );
# Note: If you omit $base, you need to encode $path first:
use Encode qw(encode_utf8);
my $relpath = decode_utf8( File::Spec->abs2rel( encode_utf8( $path ) ) );

# Example4  -- using File::Find::Rule (part1 matching a filename)
use File::Find::Rule;
use utf8;
use Encode qw(encode_utf8);
my $filename = 'æ';
# File::Find::Rule needs $filename to be encoded
my @files = File::Find::Rule->new->name( encode_utf8($filename) )->in('.');
$_ = decode_utf8( $_ ) for @files;

# Example5  -- using File::Find::Rule (part2 matching a regular expression)
use File::Find::Rule;
use utf8;
my $pat = '[æ].$'; # Unicode pattern
# Note: In this case:  File::Find::Rule->new->name( qr/$pat/ )->in('.')
#  will not work since $pat is Unicode and filenames are bytes
#  Also encoding $pat first will not work correctly
my @files;
File::Find::Rule->new->exec( sub { wanted( $pat, \@files ) } )->in('.');
$_ = decode_utf8( $_ ) for @files;
sub wanted {
    my ( $pat, $files ) = @_;
    my $name = decode_utf8( $_ );
    my $full_name = decode_utf8( $File::Find::name );
    push @$files, $full_name if $name =~ /$pat/;
}

注意：如果你擔心檔名中的 UTF-8 無效，則上述示例中 decode_utf8( ... ) 的使用應該可以替換為 decode( 'utf-8', ... )。這是因為 decode_utf8( ... ) 是 decode( 'utf8', ... ) 的同義詞，編碼 utf-8 和 utf8 之間存在差異（請參閱下面的備註以獲取更多資訊），其中 utf-8 對 utf8 的接受程度更嚴格。