| 1 | package SelectSaver; |
| 2 | |
| 3 | our $VERSION = '1.02'; |
| 4 | |
| 5 | =head1 NAME |
| 6 | |
| 7 | SelectSaver - save and restore selected file handle |
| 8 | |
| 9 | =head1 SYNOPSIS |
| 10 | |
| 11 | use SelectSaver; |
| 12 | |
| 13 | { |
| 14 | my $saver = SelectSaver->new(FILEHANDLE); |
| 15 | # FILEHANDLE is selected |
| 16 | } |
| 17 | # previous handle is selected |
| 18 | |
| 19 | { |
| 20 | my $saver = SelectSaver->new; |
| 21 | # new handle may be selected, or not |
| 22 | } |
| 23 | # previous handle is selected |
| 24 | |
| 25 | =head1 DESCRIPTION |
| 26 | |
| 27 | A C<SelectSaver> object contains a reference to the file handle that |
| 28 | was selected when it was created. If its C<new> method gets an extra |
| 29 | parameter, then that parameter is selected; otherwise, the selected |
| 30 | file handle remains unchanged. |
| 31 | |
| 32 | When a C<SelectSaver> is destroyed, it re-selects the file handle |
| 33 | that was selected when it was created. |
| 34 | |
| 35 | =cut |
| 36 | |
| 37 | require 5.000; |
| 38 | use Carp; |
| 39 | use Symbol; |
| 40 | |
| 41 | sub new { |
| 42 | @_ >= 1 && @_ <= 2 or croak 'usage: SelectSaver->new( [FILEHANDLE] )'; |
| 43 | my $fh = select; |
| 44 | my $self = bless \$fh, $_[0]; |
| 45 | select qualify($_[1], caller) if @_ > 1; |
| 46 | $self; |
| 47 | } |
| 48 | |
| 49 | sub DESTROY { |
| 50 | my $self = $_[0]; |
| 51 | select $$self; |
| 52 | } |
| 53 | |
| 54 | 1; |