$nil()

DESCRIPTION
    returns the representative null string "<<NIL>>"

SYNOPSIS
    $nil()

ARGUMENTS
    none

EXAMPLES

# pikt +C 'output $nil()'
<<NIL>>

set_fa(F)       // set age of file in days; this presupposes that (F) exists,
                // unless (F) is not supplied (invoked as:  =set_fa()) so
                // $mon, $date & $time are already known for the current file
                if "(F)" eq ""          // as with:  =set_fa()
                        set #fa = #fileage($mon,$date,$time)
                else                    // as with:  =set_fa("=passwd")
                        if ! #defined($mon)
                                set $mon = $nil()
                        fi
                        if ! #defined($date)
                                set $date = $nil()
                        fi
                        if ! #defined($time)
                                set $time = $nil()
                        fi
                        do #split($command("=lld (F)"))
                        set #fa = #fileage($[6],$[7],$[8])
                endif

SEE ALSO
    $err()

    String Functions
    Numerical Functions