You use the same commands to save or copy messages into folders as into files, except that the folder name is preceded by a plus sign (+) instead of a path name. The + tells mailx that the folder is to be kept in the folder directory (Messages).
For example, to save message 3 to a folder called projects, type:
& s 3 +projects |
mailx interprets this command as “save message 3 into ~/Messages/projects.” If the folder doesn't already exist, mailx creates it.
Copy the message into a folder by typing:
& c 3 +projects |