$PROCESS_ID

$! When referenced, $! retrieves the current value of the C

$: The current set of characters after which a string may be broken to fill continuation fields (starting with ^)

$# $# was a variable that could be used to format printed numbers. After a deprecation cycle

$LAST_REGEXP_CODE_RESULT

$CHILD_ERROR

$@ The Perl syntax error message from the last eval()

$OFS

$) The effective gid of this process. If you are on a machine that supports membership in multiple groups simultaneously, gives a space separated

$PREMATCH