Write #fd:File, [flags:Str]
Write message to file. The file fd must be a text file open for writing.
By default, this writes the message in mailbox format. This way, you can later open the file with the View Mailbox function ([Alt-M]) in PCC. That is, PCC will automatically prepend a special header to the message text, to later be able to recognize message boundaries. By specifying the second, optional parameter as "r", these headers are omitted and just the raw text is written.
Since: PCC 1.1.16, PCC2 1.99.13
