SelectSaver - 儲存並還原已選取的檔案句柄
use SelectSaver;
{
my $saver = SelectSaver->new(FILEHANDLE);
# FILEHANDLE is selected
}
# previous handle is selected
{
my $saver = SelectSaver->new;
# new handle may be selected, or not
}
# previous handle is selected
SelectSaver
物件包含在建立時所選取檔案句柄的參考。如果其 new
方法取得額外的參數,則會選取該參數;否則,已選取的檔案句柄將保持不變。
當 SelectSaver
被銷毀時,它會重新選取在建立時所選取的檔案句柄。