Default: " +TCFL"
Controls the character used to indicate mail addressed to you. The first character is the one used when the mail is NOT addressed to your address (default: space). The second is used when you are the only recipient of the message (default: +). The third is when your address appears in the TO header field, but you are not the only recipient of the message (default: T). The fourth character is used when your address is specified in the CC header field, but you are not the only recipient. The fifth character is used to indicate mail that was sent by you. The sixth character is used to indicate when a mail was sent to a mailing-list you subscribe to (default: L).