$OUTPUT_AUTOFLUSH

$& The string matched by the last successful pattern match (not counting any matches hidden within a BLOCK or

$EGID

HANDLE->autoflush( EXPR )

$EVAL_ERROR

$^A The current value of the write() accumulator

$EUID

IO::Handle->format_line_break_characters EXPR

$LAST_SUBMATCH_RESULT

HANDLE->format_lines_per_page(EXPR)