See perlvar for complete descriptions of each of the following supported "IO::Handle" methods. All of them return the previous value of the attribute and takes an optional single argument that when given will set the value. If no argument is given the previous value is unchanged (except for $io->autoflush will actually turn ON autoflush by default). $io->autoflush ( [BOOL] ) $| $io->format_page_number( [NUM] ) $% $io->format_lines_per_page( [NUM] ) $= $io->format_lines_left( [NUM] ) $- $io->format_name( [STR] ) $~ $io->format_top_name( [STR] ) $^ $io->input_line_number( [NUM]) $. The following methods are not supported on a per-filehandle basis. IO::Handle->format_line_break_characters( [STR] ) $: IO::Handle->format_formfeed( [STR]) $^L IO::Handle->output_field_separator( [STR] ) $, IO::Handle->output_record_separator( [STR] ) $\ IO::Handle->input_record_separator( [STR] ) $/