ref: 6efabda4863a13cf811575e5dbde9e33ef91c8cf
dir: /sys/man/4/upasfs/
.TH UPASFS 4 .SH NAME upasfs \- mail file server .SH SYNOPSIS .B upas/fs [ .B -DSbdfilnps ][ .B -c .I cachtarg ][ .B -f .I mailbox ][ .B -m .I mntpoint ] .SH DESCRIPTION .PP .I Fs is a user level file system that caches mailboxes and presents them as a file system. A user normally starts .I fs in his/her profile after starting .IR plumber (4) and before starting a window system, such as .IR rio (1) or .IR acme (1). The file system is used by .IR nedmail (1), .IR acme (1)'s mail reader, and .I imap4d and .I pop3 (both .IR pop3 (8)) to parse messages. .I Fs also generates plumbing messages used by .IR biff and .IR faces (1) to provide mail announcements. .PP The mailbox itself becomes a directory under .BR /mail/fs . Each message in the mailbox becomes a numbered directory in the mailbox directory, and each attachment becomes a numbered directory in the message directory. Since an attachment may itself be a mail message, this structure can recurse ad nauseam. .PP Each message and attachment directory contains the files: .TP 1.4i .B body .PD 0 the message minus the RFC2822 style headers .TP .B cc the address(es) from the CC: header .TP .B date the date in the message, or if none, the time of delivery .TP .B digest an SHA1 digest of the message contents .TP .B disposition .B inline or .B file .TP .B filename a name to use to file an attachment .TP .B flags persistant message flags as per IMAP .TP .B ffrom the parsed name of the sender .TP .B from the from address in the From: header, or if none, the address on the envelope. .TP .B header the RFC822 headers .TP .B info described below, essentially a summary of the header info .TP .B inreplyto contents of the .B in-reply-to: header .TP .B lines the number of lines in the message body .TP .B messageid the parsed RFC2822 MessageID .TP .B mimeheader the mime headers .TP .B raw the undecoded MIME message .TP .B rawbody the undecoded message body .TP .B rawheader the undecoded message header .TP .B references the parsed MessageIDs of each referenced message, one per line .TP .B replyto the address to send any replies to. .TP .B subject the contents of the subject line .TP .B to the address(es) from the To: line. .TP .B type the MIME content type .TP .B unixheader the envelope header from the mailbox .TP .B unixdate the date portion of the Unix From line. .TP .B unixdatesec the mdir filename for mdir messages. The portion before the dot is always the date from the Unix From line in seconds since epoch. .PD .PP The .B info file contains the following information, one item per line. Lists of addresses are single space separated. .IP .TP 2i .I "sender address .PD 0 .TP .I "recipient addresses .TP .I "cc addresses .TP .I "reply address .TP .I "envelope date .TP .I "subject .TP .I "MIME content type .TP .I "MIME disposition .TP .I filename .TP .I "SHA1 digest .TP .I "bcc addresses .TP .I "in-reply-to: contents .TP .I "RFC822 date .TP .I "message senders .TP .I "message id .TP .I "number of lines in body .TP .I "size of message .TP .I "message flags .TP .I unixdatesec .TP .I name from From: header .PD .PP Deleting message directories causes the message to be removed from the mailbox. .PP The mailbox is scanned and the structure updated whenever the mailbox changes. Message directories are not renumbered. The results of the scan are recorded in .IR mailbox ".idx". .PP The file .B /mail/fs/ctl is used to direct .I fs to open, close, rename, create or remove new mailboxes, and also to delete, flag, or move groups of messages atomically. The messages that can be written to this file are: .TP 2i .PD 0 .B "open \fIpath mboxname\fP opens a new mailbox. .I path is the file to open, and .I mboxname is the name that appears under .BR /mail/fs . .TP .B "close \fImboxname\fP close .IR mboxname . The close takes affect only after all files open under .BI /mail/fs/ mboxname have been closed. .TP .B "create \fImboxname\fP create a new mailbox, .BR mboxname . The mailbox type must support creation. .TP .B "rename [-t] \fIold new\fP rename the mailbox .I old to .IR new . The .I t flag truncates rather than removes the old mailbox. The renaming takes effect immedately. While mailboxes of any type may be renamed, it is not possible to use .B rename to convert folder types. .TP .B "remove [-rt] \fImboxname\fP remove .BR mboxname . The .I r flag removes any subfolders while the .I t flag truncates, rather than removes. .TP .B "delete \fImboxname number ...\fP Delete the messages with the given numbers from .IR mboxname. .TP .B "flag \fImboxname flags number ...\fP flag the given messages. .TP .B "move \fImboxname number ... target\fP Move the given messages from .IR mboxname to mailbox named .IR target. At the moment only supported with IMAP mailboxes. .PD .PP The .B flags file records persistant message flags. These flags are a superset of the standard IMAP message flags. Flags are stored in order. Unset flags are represented by a `-' while set flags are represented by the following ordered characters .TF "D .TP .B a answered .TP .B D deleted .TP .B d draft .TP .B f flagged .TP .B r recent .TP .B s seen .TP .B S stored .PD .PP Messages of the form .BI "[+-]" flags may be written to the .B flags file. Fs maintains the .I r flag. Mail readers are expected to maintain other flags. .PP The options are: .TF "-c cachetarg .TP .B -D Trace 9P protocol messages. .TP .B -S Log to console in addition to the standard places. .TP .B -b stands for biffing. Each time new mail is received, a message is printed to standard output containing the sender address, subject, and number of bytes. It is intended for people telnetting in who want mail announcements. .TP .B -c \fIcachetarg\fP attempt to keep the cache below .I cachetarg bytes. .TP .B -d loud debugging. .TP .B -f \fIfile\fP use .I file as the mailbox instead of the default, .BI /mail/box/ username /mbox. .PD 0 .TP .B -i chatty index debugging. .TP .B -l logging. Turn on logging via syslog (and to the console with -\fIS\fP) to the file .BR /sys/log/fs . .TP .B -m \fImntpt\fP mount on .I mntpt rather than the default .BR /mail/fs . .TP .B -n Don't open a mailbox initially. Overridden by -f. .TP .B -p turn off plumbing. Unless this is specified, .I fs sends a message to the plumb port, .BR seemail , from source .B mailfs for each message received or deleted. The message contains the attributes .IR sender = "<contents of from file>" , .IR filetype =mail, .IR mailtype = "deleted or new" , and .IR length = "<message length in bytes>" . The contents of the message is the full path name of the directory representing the message. .TP .B -s causes .I fs to put itself in .B /srv with a name of the form .BR /srv/upasfs.\fIuser\fP . .PD .PP .I Fs will exit once all references to its directory have disappeared. .PP .I Fs interprets mailbox file names of the form .BI / proto / host / user to mean access an account on .I host using the given protocol. Authentication is delegated to .IR factotum (4). The final .BI / user may be omitted, in which case the user name is gleaned from the key held by .IR factotum . The following protocols are supported: .PP .TF apoptls .TP .B pop cleartext POP with password authentication .TP .B apop cleartext POP with challenge-response (APOP) authentication .TP .B poptls TLS-encrypted POP with password authentication .TP .B apoptls TLS-encrypted POP with challenge-response (APOP) authentication .TP .B imap cleartext IMAP with CRAM-MD5 or password authentication .TP .B imaps TLS-encrypted IMAP CRAM-MD5 or password authentication .PD .PP The two IMAP protocols allow an optional fourth field specifying a mailbox name, for example .BR /imap/server/user/stored . .PP .B Poptls and .B apoptls connect to port 110 in plaintext and start TLS using the POP STLS command. .B Imaps connects to port 993 and starts TLS before initiating the IMAP conversation. There should probably be .BR pops , .BR apops , and .B imaptls protocols as well. .RB ( Pops and .B apops would connect to port 995 and start TLS before initiating the POP conversation, and .B imaptls would connect to port 143 in plaintext and start TLS using the IMAP STARTTLS command. (That's the nice thing about standards\(emthere's so many to choose from.)) .SH FILES .TF /mail/box/*/dead.letter .TP .B /mail/box/* mail directories .TP .B /mail/box/*/mbox mailbox files .TP .B /mail/box/*/\fImbox\fP.idx mailbox indicies .TP .B /mail/box/*/L.mbox mutual exclusion lock for altering mbox (mbox format only) .SH SOURCE .TP .B /sys/src/cmd/upas/fs .SH "SEE ALSO" .IR aliasmail (8), .IR faces (1), .IR filter (1), .IR mail (1), .IR marshal (1), .IR mdir (6), .IR mlmgr (1), .IR nedmail (1), .IR pop3 (8), .IR qer (8), .IR rewrite (6), .IR send (8) .br Erik Quanstrom ``Scaling Upas'', Proceedings of IWP9, October, 2008.