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Add new upstream manpages

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.\" -*-nroff-*-
.\"
.\"
.\" Copyright (C) 1996-2018 Michael R. Elkins <me@cs.hmc.edu>
.\"
.\" This program is free software; you can redistribute it and/or modify
.\" it under the terms of the GNU General Public License as published by
.\" the Free Software Foundation; either version 2 of the License, or
.\" (at your option) any later version.
.\"
.\" This program is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public License
.\" along with this program; if not, write to the Free Software
.\" Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
.\"
.TH mutt 1 "January 2009" Unix "User Manuals"
.SH NAME
mutt \- The Mutt Mail User Agent
.SH SYNOPSIS
.PP
.B mutt
[\-nRyzZ]
[\-e \fIcmd\fP] [\-F \fIfile\fP] [\-m \fItype\fP] [\-f \fIfile\fP]
.PP
.B mutt
[\-Enx]
[\-e \fIcmd\fP]
[\-F \fIfile\fP]
[\-H \fIfile\fP]
[\-i \fIfile\fP]
[\-s \fIsubj\fP]
[\-b \fIaddr\fP]
[\-c \fIaddr\fP]
[\-a \fIfile\fP [...] \-\-]
\fIaddr|mailto_url\fP [...]
.PP
.B mutt
[\-nx]
[\-e \fIcmd\fP]
[\-F \fIfile\fP]
[\-s \fIsubj\fP]
[\-b \fIaddr\fP]
[\-c \fIaddr\fP]
[\-a \fIfile\fP [...] \-\-]
\fIaddr|mailto_url\fP [...]
< message
.PP
.B mutt
[\-n] [\-e \fIcmd\fP] [\-F \fIfile\fP] \-p
.PP
.B mutt
[\-n] [\-e \fIcmd\fP] [\-F \fIfile\fP] \-A \fIalias\fP
.PP
.B mutt
[\-n] [\-e \fIcmd\fP] [\-F \fIfile\fP] \-Q \fIquery\fP
.PP
.B mutt
\-v[v]
.PP
.B mutt
\-D
.SH DESCRIPTION
.PP
Mutt is a small but very powerful text based program for reading and sending electronic
mail under unix operating systems, including support for color terminals, MIME,
OpenPGP, and a threaded sorting mode.
.PP
.I Note:
.IR
This manual page gives a brief overview of mutt's command line
options. You should find a copy of the full manual in /usr/share/doc/mutt, in
text, HTML, and/or PDF format.
.SH OPTIONS
.PP
.IP "-A \fIalias\fP"
An expanded version of the given alias is passed to stdout.
.IP "-a \fIfile\fP [...]"
Attach a file to your message using MIME.
When attaching single or multiple files, separating filenames and recipient addresses with
"\-\-" is mandatory, e.g. \fBmutt \-a image.jpg \-\- addr1\fP or
\fBmutt \-a img.jpg *.png \-\- addr1 addr2\fP.
The \-a option must be placed at the end of command line options.
.IP "-b \fIaddress\fP"
Specify a blind-carbon-copy (BCC) recipient
.IP "-c \fIaddress\fP"
Specify a carbon-copy (CC) recipient
.IP "-d \fIlevel\fP"
If mutt was compiled with +DEBUG log debugging output to ~/.muttdebug0.
\fILevel\fP can range from 1-5 and effects verbosity. A value of 2 is
recommended.
.IP "-D"
Print the value of all configuration options to stdout.
.IP "-E"
Causes the draft file specified by -H or include file specified by -i
to be edited during message composition.
.IP "-e \fIcommand\fP"
Specify a configuration command to be run after processing of initialization
files.
.IP "-f \fImailbox\fP"
Specify which mailbox to load.
.IP "-F \fImuttrc\fP"
Specify an initialization file to read instead of ~/.muttrc
.IP "-h"
Display help.
.IP "-H \fIdraft\fP"
Specify a draft file which contains header and body to use to send a
message.
.IP "-i \fIinclude\fP"
Specify a file to include into the body of a message.
.IP "-m \fItype\fP "
specify a default mailbox type for newly created folders.
.IP "-n"
Causes Mutt to bypass the system configuration file.
.IP "-p"
Resume a postponed message.
.IP "-Q \fIquery\fP"
Query a configuration variables value. The query is executed after
all configuration files have been parsed, and any commands given on
the command line have been executed.
.IP "-R"
Open a mailbox in \fIread-only\fP mode.
.IP "-s \fIsubject\fP"
Specify the subject of the message.
.IP "-v"
Display the Mutt version number and compile-time definitions.
.IP "-vv"
Display license and copyright information.
.IP "-x"
Emulate the mailx compose mode.
.IP "-y"
Start Mutt with a listing of all mailboxes specified by the \fImailboxes\fP
command.
.IP "-z"
When used with \-f, causes Mutt not to start if there are no messages in the
mailbox.
.IP "-Z"
Causes Mutt to open the first mailbox specified by the \fImailboxes\fP
command which contains new mail.
.IP "--"
Treat remaining arguments as \fIaddr\fP even if they start with a dash.
See also "\-a" above.
.SH ENVIRONMENT
.PP
.IP "EDITOR"
Specifies the editor to use if VISUAL is unset.
.IP "EMAIL"
The user's e-mail address.
.IP "HOME"
Full path of the user's home directory.
.IP "MAIL"
Full path of the user's spool mailbox.
.IP "MAILDIR"
Full path of the user's spool mailbox if MAIL is unset. Commonly used when the spool
mailbox is a
.B maildir (5)
folder.
.IP "MAILCAPS"
Path to search for mailcap files.
.IP "MM_NOASK"
If this variable is set, mailcap are always used without prompting first.
.IP "PGPPATH"
Directory in which the user's PGP public keyring can be found. When used with
the original PGP program, mutt and
.B pgpring (1)
rely on this being set.
.IP "TMPDIR"
Directory in which temporary files are created.
.IP "REPLYTO"
Default Reply-To address.
.IP "VISUAL"
Specifies the editor to use when composing messages.
.SH FILES
.PP
.IP "~/.muttrc or ~/.mutt/muttrc"
User configuration file.
.IP "/etc/Muttrc"
System-wide configuration file.
.IP "/tmp/muttXXXXXX"
Temporary files created by Mutt.
.IP "~/.mailcap"
User definition for handling non-text MIME types.
.IP "/etc/mailcap"
System definition for handling non-text MIME types.
.IP "~/.mime.types"
User's personal mapping between MIME types and file extensions.
.IP "/etc/mime.types"
System mapping between MIME types and file extensions.
.IP "/usr/bin/mutt_dotlock"
The privileged dotlocking program.
.IP "/usr/share/doc/mutt/manual.txt.gz"
The Mutt manual.
.SH BUGS
.PP
None. Mutts have fleas, not bugs.
.SH FLEAS
.PP
Suspend/resume while editing a file with an external editor does not work
under SunOS 4.x if you use the curses lib in /usr/5lib. It \fIdoes\fP work
with the S-Lang library, however.
.PP
Resizing the screen while using an external pager causes Mutt to go haywire
on some systems.
.PP
Suspend/resume does not work under Ultrix.
.PP
The help line for the index menu is not updated if you change the bindings
for one of the functions listed while Mutt is running.
.PP
For a more up-to-date list of bugs, errm, fleas, please visit the
mutt project's bug tracking system under https://gitlab.com/muttmua/mutt/issues.
.SH NO WARRANTIES
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
.SH SEE ALSO
.PP
.BR curses (3),
.BR mailcap (5),
.BR maildir (5),
.BR mbox (5),
.BR mutt_dotlock (1),
.BR muttrc (5),
.BR ncurses (3),
.BR sendmail (1),
.BR smail (1).
.PP
Mutt Home Page: http://www.mutt.org/
.PP
The Mutt manual
.SH AUTHOR
.PP
Michael Elkins, and others. Use <mutt-dev@mutt.org> to contact
the developers.
.\" -*-nroff-*-
.\"
.\"
.\" Copyright (C) 1996-8 Michael R. Elkins <me@cs.hmc.edu>
.\" Copyright (C) 1998-9 Thomas Roessler <roessler@does-not-exist.org>
.\"
.\" This program is free software; you can redistribute it and/or modify
.\" it under the terms of the GNU General Public License as published by
.\" the Free Software Foundation; either version 2 of the License, or
.\" (at your option) any later version.
.\"
.\" This program is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public License
.\" along with this program; if not, write to the Free Software
.\" Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
.\"
.TH dotlock 1 "AUGUST 1999" Unix "User Manuals"
.SH NAME
mutt_dotlock \- Lock mail spool files.
.SH SYNOPSIS
.PP
.B mutt_dotlock
[\-t|\-f|\-u|\-d] [\-p] [\-r \fIretries\fP] \fIfile\fP
.SH DESCRIPTION
.PP
.B mutt_dotlock
implements the traditional mail spool file locking method:
To lock \fIfile\fP, a file named \fIfile\fP.lock is
created. The program operates with group mail privileges
if necessary.
.SH OPTIONS
.PP
.IP "-t"
Just try.
.B mutt_dotlock
won't actually lock a file, but inform the invoking
process if it's at all possible to lock \fIfile\fP.
.IP "-f"
Force the lock. If another process holds a lock on
\fIfile\fP longer than a certain amount of time,
.B mutt_dotlock
will break that lock by removing the lockfile.
.IP "-u"
Unlock.
.B mutt_dotlock
will remove \fIfile\fP.lock.
.IP "-d"
Delete.
.B mutt_dotlock
will lock \fIfile\fP, remove it if it has length 0, and afterwards
remove \fIfile\fP.lock.
.IP "-p"
Use privileges. If given this option,
.B mutt_dotlock
will operate with group mail privileges when creating and
deleting lock files.
.IP "-r \fIretries\fP"
This command line option tells
.B mutt_dotlock
to try locking
\fIretries\fP times before giving up or (if invoked with
the
.B -f
command line option) break a lock. The default value is 5.
.B mutt_dotlock
waits one second between successive locking attempts.
.SH FILES
.PP
.IP "\fIfile\fP.lock"
The lock file
.B mutt_dotlock
generates.
.SH SEE ALSO
.PP
.BR fcntl (2),
.BR flock (2),
.BR lockfile (1),
.BR mutt (1)
.SH DIAGNOSTICS
.PP
.B mutt_dotlock
gives all diagnostics in its return values:
.TP
.B "0 \- DL_EX_OK"
The program was successful.
.TP
.B "1 \- DL_EX_ERROR"
An unspecified error such as bad command line parameters,
lack of system memory and the like has occurred.
.TP
.B "3 \- DL_EX_EXIST"
The
user wants to lock a file which has been locked by
another process already. If
.B mutt_dotlock
is invoked with the
.B -f
command line option,
.B mutt_dotlock
won't generate this error, but break other processes'
locks.
.TP
.B "4 \- DL_EX_NEED_RPIVS"
This return value only occurs if
.B mutt_dotlock
has been invoked
with the
.B -t
command line option. It means that
.B mutt_dotlock
will have to use its group mail privileges to lock
\fIfile\fP.
.TP
.B "5 \- DL_EX_IMPOSSIBLE"
This return value only occurs if
.B mutt_dotlock
has been invoked with the
.B -t
command line option. It means that
.B mutt_dotlock
is unable to lock \fIfile\fP even with group mail
privileges.
.SH NOTES
.PP
.B mutt_dotlock
tries to implement an NFS-safe dotlocking method which was
borrowed from
.B lockfile
(1).
.PP
If the user can't open \fIfile\fP for reading with his
normal privileges,
.B mutt_dotlock
will return the
.B DL_EX_ERROR
exit value to avoid certain attacks against other users'
spool files. The code carefully avoids race conditions
when checking permissions; for details of all this see the
comments in dotlock.c.
.SH HISTORY
.PP
.B mutt_dotlock
is part of the Mutt mail user agent package. It has been
created to avoid running mutt with group mail privileges.
.SH AUTHOR
Thomas Roessler <roessler@does-not-exist.org>
.\" -*-nroff-*-
.\"
.\"
.\" Copyright (C) 2001,2002 Oliver Ehli <elmy@acm.org>
.\" Copyright (C) 2001 Mike Schiraldi <raldi@research.netsol.com>
.\" Copyright (C) 2003 Bjoern Jacke <bjoern@j3e.de>
.\" Copyright (C) 2015 Kevin J. McCarthy <kevin@8t8.us>
.\"
.\" This program is free software; you can redistribute it and/or modify
.\" it under the terms of the GNU General Public License as published by
.\" the Free Software Foundation; either version 2 of the License, or
.\" (at your option) any later version.
.\"
.\" This program is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public License
.\" along with this program; if not, write to the Free Software
.\" Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
.\"
.TH smime_keys 1 "May 2009" Unix "User Manuals"
.SH "NAME"
smime_keys \- Utility to add S/MIME certificate to the internal database used by mutt
.SH SYNOPSIS
.PP
.B smime_keys
<operation> [file(s) | keyID [file(s)]]
.SH "DESCRIPTION"
The purpose of this tool is to manipulate the internal database of S/MIME certificates
used by mutt to sign mail messages which will be sent or to verify mail messages received
and signed with S/MIME
.SH OPTIONS
.PP
.IP \fBinit\fP
no files needed, inits directory structure.
.IP \fBlist\fP
lists the certificates stored in database.
.IP \fBlabel\fP
keyID required. changes/removes/adds label.
.IP \fBremove\fP
keyID required.
.IP \fBverify\fP
1=keyID and optionally 2=CRL
Verifies the certificate chain, and optionally whether
this certificate is included in supplied CRL (PEM format).
Note: to verify all certificates at the same time,
replace keyID with "all"
.IP \fBadd_cert\fP
certificate required.
.IP \fBadd_chain\fP
three files reqd: 1=Key, 2=certificate
plus 3=intermediate certificate(s).
.IP \fBadd_p12\fP
one file reqd. Adds keypair to database.
file is PKCS12 (e.g. export from netscape).
.IP \fBadd_pem\fP
one file reqd. Adds keypair to database.
(file was converted from e.g. PKCS12).
.IP \fBadd_root\fP
one file reqd. Adds PEM root certificate to the location
specified within muttrc (smime_verify_* command)
.SH NO WARRANTIES
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
.PP
Mutt Home Page: http://www.mutt.org/
'\" t
.\" -*-nroff-*-
.\"
.\" Copyright (C) 2000 Thomas Roessler <roessler@does-not-exist.org>
.\"
.\" This document is in the public domain and may be distributed and
.\" changed arbitrarily.
.\"
.TH mbox 5 "February 19th, 2002" Unix "User Manuals"
.\"
.SH NAME
mbox \- Format for mail message storage.
.\"
.SH DESCRIPTION
This document describes the format traditionally used by Unix hosts
to store mail messages locally.
.B mbox
files typically reside in the system's mail spool, under various
names in users' Mail directories, and under the name
.B mbox
in users' home directories.
.PP
An
.B mbox
is a text file containing an arbitrary number of e-mail messages.
Each message consists of a postmark, followed by an e-mail message
formatted according to \fBRFC822\fP, \fBRFC2822\fP. The file format
is line-oriented. Lines are separated by line feed characters (ASCII 10).
.PP
A postmark line consists of the four characters "From", followed by
a space character, followed by the message's envelope sender
address, followed by whitespace, and followed by a time stamp. This
line is often called From_ line.
.PP
The sender address is expected to be
.B addr-spec
as defined in \fBRFC2822\fP 3.4.1. The date is expected to be
.B date-time
as output by
.BR asctime(3) .
For compatibility reasons with legacy software, two-digit years
greater than or equal to 70 should be interpreted as the years
1970+, while two-digit years less than 70 should be interpreted as
the years 2000-2069. Software reading files in this format should
also be prepared to accept non-numeric timezone information such as
"CET DST" for Central European Time, daylight saving time.
.PP
Example:
.IP "" 1
>From example@example.com Fri Jun 23 02:56:55 2000
.PP
In order to avoid misinterpretation of lines in message bodies
which begin with the four characters "From", followed by a space
character, the mail delivery agent must quote any occurrence
of "From " at the start of a body line.
.sp
There are two different quoting schemes, the first (\fBMBOXO\fP) only
quotes plain "From " lines in the body by prepending a '>' to the
line; the second (\fBMBOXRD\fP) also quotes already quoted "From "
lines by prepending a '>' (i.e. ">From ", ">>From ", ...). The later
has the advantage that lines like
.IP "" 1
>From the command line you can use the '\-p' option
.PP
aren't dequoted wrongly as a \fBMBOXRD\fP-MDA would turn the line
into
.IP "" 1
>>From the command line you can use the '\-p' option
.PP
before storing it. Besides \fBMBOXO\fP and \fBMBOXRD\fP there is also
\fBMBOXCL\fP which is \fBMBOXO\fP with a "Content-Length:"\-field with the
number of bytes in the message body; some MUAs (like
.BR mutt (1))
do automatically transform \fBMBOXO\fP mailboxes into \fBMBOXCL\fP ones when
ever they write them back as \fBMBOXCL\fP can be read by any \fBMBOXO\fP-MUA
without any problems.
.PP
If the modification-time (usually determined via
.BR stat (2))
of a nonempty
.B mbox
file is greater than the access-time the file has new mail. Many MUAs
place a Status: header in each message to indicate which messages have
already been read.
.\"
.SH LOCKING
Since
.B mbox
files are frequently accessed by multiple programs in parallel,
.B mbox
files should generally not be accessed without locking.
.PP
Three different locking mechanisms (and combinations thereof) are in
general use:
.IP "\(bu"
.BR fcntl (2)
locking is mostly used on recent, POSIX-compliant systems. Use of
this locking method is, in particular, advisable if
.B mbox
files are accessed through the Network File System (NFS), since it
seems the only way to reliably invalidate NFS clients' caches.
.IP "\(bu"
.BR flock (2)
locking is mostly used on BSD-based systems.
.IP "\(bu"
Dotlocking is used on all kinds of systems. In order to lock an
.B mbox
file named \fIfolder\fR, an application first creates a temporary file
with a unique name in the directory in which the
\fIfolder\fR resides. The application then tries to use the
.BR link (2)
system call to create a hard link named \fIfolder.lock\fR
to the temporary file. The success of the
.BR link (2)
system call should be additionally verified using
.BR stat (2)
calls. If the link has succeeded, the mail folder is considered
dotlocked. The temporary file can then safely be unlinked.
.IP ""
In order to release the lock, an application just unlinks the
\fIfolder.lock\fR file.
.PP
If multiple methods are combined, implementors should make sure to
use the non-blocking variants of the
.BR fcntl (2)
and
.BR flock (2)
system calls in order to avoid deadlocks.
.PP
If multiple methods are combined, an
.B mbox
file must not be considered to have been successfully locked before
all individual locks were obtained. When one of the individual
locking methods fails, an application should release all locks it
acquired successfully, and restart the entire locking procedure from
the beginning, after a suitable delay.
.PP
The locking mechanism used on a particular system is a matter of
local policy, and should be consistently used by all applications
installed on the system which access
.B mbox
files. Failure to do so may result in loss of e-mail data, and in
corrupted
.B mbox
files.
.\"
.SH FILES
.IR /var/spool/mail/$LOGNAME
.RS
\fB$LOGNAME\fP's incoming mail folder.
.RE
.PP
.IR $HOME/mbox
.RS
user's archived mail messages, in his \fB$HOME\fP directory.
.RE
.PP
.IR $HOME/Mail/
.RS
A directory in user's \fB$HOME\fP directory which is commonly used to hold
.B mbox
format folders.
.RE
.PP
.\"
.SH "SEE ALSO"
.BR mutt (1),
.BR fcntl (2),
.BR flock (2),
.BR link (2),
.BR stat (2),
.BR asctime (3),
.BR maildir (5),
.BR mmdf (5),
.BR RFC822 ,
.BR RFC976 ,
.BR RFC2822
.\"
.SH AUTHOR
Thomas Roessler <roessler@does-not-exist.org>, Urs Janssen <urs@tin.org>
.\"
.SH HISTORY
The
.B mbox
format occurred in Version 6 AT&T Unix.
.br
A variant of this format was documented in \fBRFC976\fP.
.\" Project : tin
.\" Module : mmdf.5
.\" Author : U. Janssen
.\" Created : 2002-02-18
.\" Updated :
.\" Notes : needs a lot of work
.\"
.TH mmdf 5 "February 18th, 2002" "Unix" "User Manuals"
.\"
.SH NAME
MMDF \- Multi\-channel Memorandum Distribution Facility mailbox format
.\"
.SH DESCRIPTION
This document describes the
.B MMDF
mailbox format used by some MTAs and MUAs (i.e.
.BR scomail (1))
to store mail messages locally.
.PP
An
.B MMDF
mailbox is a text file containing an arbitrary number of e-mail messages.
Each message consists of a postmark, followed by an e-mail message formatted
according to \fBRFC822\fP / \fBRFC2822\fP, followed by a postmark. The file
format is line-oriented. Lines are separated by line feed characters (ASCII
10). A postmark line consists of the four characters "^A^A^A^A" (Control-A;
ASCII 1).
.TP
Example of a \fBMMDF\fP mailbox holding two mails:
.RS
.nf
.sp
^A^A^A^A
.br
From: example@example.com
.br
To: example@example.org
.br
Subject: test
.br
.sp
.br
>From what I learned about the MMDF-format:
.br
.br
^A^A^A^A
.br
^A^A^A^A
.br
From: example@example.com
.br
To: example@example.org
.br
Subject: test 2
.br
.sp
.br
bar
.br
^A^A^A^A
.fi
.RE
.PP
In contrast to most other single file mailbox formats like
MBOXO and MBOXRD (see
.BR mbox (5))
there is no need to quote/dequote "From "\-lines in
.B MMDF
mailboxes as such lines have no special meaning in this format.
.PP
If the modification-time (usually determined via
.BR stat (2))
of a nonempty mailbox file is greater than the access-time
the file has new mail. Many MUAs place a Status: header in
each message to indicate which messages have already been
read.
.\"
.SH LOCKING
Since
.B MMDF
files are frequently accessed by multiple programs in parallel,
.B MMDF
files should generally not be accessed without locking.
.PP
Three different locking mechanisms (and combinations thereof) are in
general use:
.IP "\(bu"
.BR fcntl (2)
locking is mostly used on recent, POSIX-compliant systems. Use of
this locking method is, in particular, advisable if
.B MMDF
files are accessed through the Network File System (NFS), since it
seems the only way to reliably invalidate NFS clients' caches.
.IP "\(bu"
.BR flock (2)
locking is mostly used on BSD-based systems.
.IP "\(bu"
Dotlocking is used on all kinds of systems. In order to lock an
.B MMDF
file named \fIfolder\fR, an application first creates a temporary file
with a unique name in the directory in which the
\fIfolder\fR resides. The application then tries to use the
.BR link (2)
system call to create a hard link named \fIfolder.lock\fR
to the temporary file. The success of the
.BR link (2)
system call should be additionally verified using
.BR stat (2)
calls. If the link has succeeded, the mail folder is considered
dotlocked. The temporary file can then safely be unlinked.
.IP ""
In order to release the lock, an application just unlinks the
\fIfolder.lock\fR file.
.PP
If multiple methods are combined, implementors should make sure to
use the non-blocking variants of the
.BR fcntl (2)
and
.BR flock (2)
system calls in order to avoid deadlocks.
.PP
If multiple methods are combined, an
.B MMDF
file must not be considered to have been successfully locked before
all individual locks were obtained. When one of the individual
locking methods fails, an application should release all locks it
acquired successfully, and restart the entire locking procedure from
the beginning, after a suitable delay.
.PP
The locking mechanism used on a particular system is a matter of
local policy, and should be consistently used by all applications
installed on the system which access
.B MMDF
files. Failure to do so may result in loss of e-mail data, and in
corrupted
.B MMDF
files.