Nearly all commands have the following common options:
-@table @code
+@table @option
+@item -cfg
+ Path to configuration file. May be overridden by @env{NNCPCFG}
+ environment variable. If file file is an encrypted @ref{EBlob,
+ eblob}, then ask for passphrase to decrypt it first.
@item -debug
Print debug messages. Normally this option should not be used.
+@item -minsize
+ @anchor{OptMinSize}
+ Minimal required resulting packet size, in KiBs. For example if you
+ send 2 KiB file and set @option{-minsize 4}, then resulting packet
+ will be 4 KiB (containing file itself and some junk).
@item -nice
- Set desired outgoing packet niceness level. 1-255 values are
- allowed. Higher value means lower priority. In some commands that
- means processing of packets that have equal or lower nice value.
- That is used for controlling network QoS.
-@item -node
- Process only single specified node.
+ Set desired outgoing packet @ref{Niceness, niceness level}.
+@item -replynice
+ Set desired reply packet @ref{Niceness, niceness level}. Only freq
+ and exec packets look at that niceness level.
+@item -via
+ Override @ref{CfgVia, via} configuration option for destination node.
+ Specified nodes must be separated with comma: @verb{|NODE1,NODE2|}.
+ With @verb{|-via -|} you can disable relaying at all.
+@item -spool
+ Override path to spool directory. May be specified by
+ @env{NNCPSPOOL} environment variable.
+@item -log
+ Override path to logfile. May be specified by @env{NNCPLOG}
+ environment variable.
@item -quiet
Print only errors, omit simple informational messages. In any case
those messages are logged, so you can reread them using
@ref{nncp-log} command.
+@item -progress, -noprogress
+ Either force progress showing, or disable it.
@item -version
Print version information.
@item -warranty
Print warranty information (no warranty).
@end table
+@node nncp-bundle
+@section nncp-bundle
+
+@verbatim
+$ nncp-bundle [options] -tx [-delete] NODE [NODE ...] > ...
+$ nncp-bundle [options] -rx -delete [-dryrun] [NODE ...] < ...
+$ nncp-bundle [options] -rx [-check] [-dryrun] [NODE ...] < ...
+@end verbatim
+
+With @option{-tx} option, this command creates @ref{Bundles, bundle} of
+@ref{Encrypted, encrypted packets} from the spool directory and writes
+it to stdout.
+
+With @option{-rx} option, this command takes bundle from stdin and
+copies all found packets for our node to the spool directory. Pay
+attention that @strong{no} integrity checking is done by default. Modern
+tape drives could easily provide too much throughput your CPU won't be
+able to verify on the fly. So if you won't @ref{nncp-toss, toss}
+received packets at the place, it is advisable either to run
+@ref{nncp-check} utility for packets integrity verification, or to use
+@option{-check} option to enable on the fly integrity check.
+
+You can specify multiple @option{NODE} arguments, telling for what nodes
+you want to create the stream, or take it from. If no nodes are
+specified for @option{-rx} mode, then all packets aimed at us will be
+processed.
+
+When packets are sent through the stream, they are still kept in the
+spool directory, because there is no assurance that they are transferred
+to the media (media (CD-ROM, tape drive, raw hard drive) can end). If
+you want to forcefully delete them (after they are successfully flushed
+to stdout) anyway, use @option{-delete} option.
+
+But you can verify produced stream after, by digesting it by yourself
+with @option{-rx} and @option{-delete} options -- in that mode, stream
+packets integrity will be checked and they will be deleted from the
+spool if everything is good. So it is advisable to recheck your streams:
+
+@verbatim
+$ nncp-bundle -tx ALICE BOB WHATEVER | cdrecord -tao -
+$ dd if=/dev/cd0 bs=2048 | nncp-bundle -rx -delete
+@end verbatim
+
+@option{-dryrun} option prevents any writes to the spool. This is
+useful when you need to see what packets will pass by and possibly check
+their integrity.
+
@node nncp-call
@section nncp-call
@verbatim
-% nncp-call [options] [-rx|-tx] NODE[:ADDR] [FORCEADDR]
+$ nncp-call [options]
+ [-onlinedeadline INT]
+ [-maxonlinetime INT]
+ [-rx|-tx]
+ [-list]
+ [-pkts PKT,PKT,...]
+ [-rxrate INT]
+ [-txrate INT]
+ NODE[:ADDR] [FORCEADDR]
@end verbatim
-Call (connect to) specified @code{NODE} and run @ref{Sync,
+Call (connect to) specified @option{NODE} and run @ref{Sync,
synchronization} protocol with the @ref{nncp-daemon, daemon} on the
remote side. Normally this command could be run any time you wish to
either check for incoming packets, or to send out queued ones.
Synchronization protocol allows resuming and bidirectional packets
transfer.
-If @code{-rx} option is specified then only inbound packets transmission
-is performed. If @code{-tx} option is specified, then only outbound
-transmission is performed.
+If @option{-rx} option is specified then only inbound packets
+transmission is performed. If @option{-tx} option is specified, then
+only outbound transmission is performed. @option{-onlinedeadline}
+overrides @ref{CfgOnlineDeadline, @emph{onlinedeadline}}.
+@option{-maxonlinetime} overrides @ref{CfgMaxOnlineTime,
+@emph{maxonlinetime}}. @option{-rxrate}/@option{-txrate} override
+@ref{CfgXxRate, rxrate/txrate}. @option{-list} option allows you to list
+packets of remote node, without any transmission.
-Each @code{NODE} can contain several uniquely identified
-@code{ADDR}esses in @ref{Configuration, configuration} file. If you do
+You can specify what packets your want to download, by specifying
+@option{-pkts} option with comma-separated list of packets identifiers.
+
+Each @option{NODE} can contain several uniquely identified
+@option{ADDR}esses in @ref{CfgAddrs, configuration} file. If you do
not specify the exact one, then all will be tried until the first
-success. Optionally you can force @code{FORCEADDR} address usage,
-instead of addresses taken from configuration file.
+success. Optionally you can force @option{FORCEADDR} address usage,
+instead of addresses taken from configuration file. You can specify both
+@verb{|host:port|} and @verb{#|some command#} formats.
-Pay attention that this command run integrity check for each completely
-received packet in the background. This can be time consuming and
-connection could be lost during that check time and remote node won't be
+Pay attention that this command runs integrity check for each completely
+received packet in the background. This can be time consuming.
+Connection could be lost during that check and remote node won't be
notified that file is done. But after successful integrity check that
-file will be renamed from @code{.part} one and when you rerun
-@code{nncp-call} again, remote node will receive completion at once.
+file is renamed from @file{.part} one and when you rerun
+@command{nncp-call} again, remote node will receive completion
+notification.
+
+@node nncp-caller
+@section nncp-caller
+
+@verbatim
+$ nncp-caller [options] [NODE ...]
+@end verbatim
+
+Croned daemon that calls remote nodes from time to time, according to
+their @ref{CfgCalls, @emph{calls}} configuration field.
+
+Optional number of @option{NODE}s tells to ignore other ones.
+Otherwise all nodes with specified @emph{calls} configuration
+field will be called.
+
+Look @ref{nncp-call} for more information.
+
+@node nncp-cfgenc
+@section nncp-cfgenc
+
+@verbatim
+$ nncp-cfgmin [options] [-s INT] [-t INT] [-p INT] cfg.hjson > cfg.hjson.eblob
+$ nncp-cfgmin [options] -d cfg.hjson.eblob > cfg.hjson
+@end verbatim
+
+This command allows you to encrypt provided @file{cfg.hjson} file with
+the passphrase, producing @ref{EBlob, eblob}, to safely keep your
+configuration file with private keys. This utility was written for users
+who do not want (or can not) to use either @url{https://gnupg.org/,
+GnuPG} or similar tools. That @file{eblob} file can be used directly in
+@option{-cfg} option of nearly all commands.
+
+@option{-s}, @option{-t}, @option{-p} are used to tune @file{eblob}'s
+password strengthening function. Space memory cost (@option{-s}),
+specified in number of BLAKE2b-256 blocks (32 bytes), tells how many
+memory must be used for hashing -- bigger values are better, but slower.
+Time cost (@option{-t}) tells how many rounds/iterations must be
+performed -- bigger is better, but slower. Number of parallel jobs
+(@option{-p}) tells how many computation processes will be run: this is
+the same as running that number of independent hashers and then joining
+their result together.
+
+When invoked for encryption, passphrase is entered manually twice. When
+invoked for decryption (@option{-d} option), it is asked once and exits
+if passphrase can not decrypt @file{eblob}.
+
+@option{-dump} options parses @file{eblob} and prints parameters used
+during its creation. For example:
+@verbatim
+$ nncp-cfgenc -dump /usr/local/etc/nncp.hjson.eblob
+Strengthening function: Balloon with BLAKE2b-256
+Memory space cost: 1048576 bytes
+Number of rounds: 16
+Number of parallel jobs: 2
+Blob size: 2494
+@end verbatim
+
+@node nncp-cfgmin
+@section nncp-cfgmin
+
+@verbatim
+$ nncp-cfgmin [options] > stripped.hjson
+@end verbatim
+
+Print out stripped configuration version: only path to @ref{Spool,
+spool}, path to log file, neighbours public keys are stayed. This is
+useful mainly for usage with @ref{nncp-xfer} that has to know only
+neighbours, without private keys involving.
+
+@node nncp-cfgnew
+@section nncp-cfgnew
+
+@verbatim
+$ nncp-cfgnew [options] [-nocomments] > new.hjson
+@end verbatim
+
+Generate new node configuration: private keys, example configuration
+file and print it to stdout. You must use this command when you setup
+the new node. @option{-nocomments} will create configuration file
+without descriptive huge comments -- useful for advanced users.
+
+Pay attention that private keys generation consumes an entropy from your
+operating system.
@node nncp-check
@section nncp-check
@verbatim
-% nncp-check [options]
+$ nncp-check [options]
@end verbatim
Perform @ref{Spool, spool} directory integrity check. Read all files
that has Base32-encoded filenames and compare it with recalculated
-BLAKE2b hash output of their contents. This supplementary command are
+BLAKE2b hash output of their contents. That supplementary command is
not used often in practice, if ever.
@node nncp-daemon
@section nncp-daemon
@verbatim
-% nncp-daemon [options] [-maxconn INT] [-bind ADDR]
+$ nncp-daemon [options] [-maxconn INT] [-bind ADDR] [-inetd]
@end verbatim
Start listening TCP daemon, wait for incoming connections and run
@ref{nncp-toss} utility in background to process inbound packets from
time to time.
-@code{-maxconn} option specifies how many simultaneous clients daemon
-can handle. @code{-bind} option specifies @code{addr:port} it must bind
-to and listen.
+@option{-maxconn} option specifies how many simultaneous clients daemon
+can handle. @option{-bind} option specifies @option{addr:port} it must
+bind to and listen.
+
+It could be run as @command{inetd} service, by specifying
+@option{-inetd} option. Example inetd-entry:
+
+@verbatim
+uucp stream tcp6 nowait nncpuser /usr/local/bin/nncp-daemon nncp-daemon -inetd
+@end verbatim
+
+@node nncp-exec
+@section nncp-exec
+
+@verbatim
+$ nncp-exec [options] NODE HANDLE [ARG0 ARG1 ...]
+@end verbatim
+
+Send execution command to @option{NODE} for specified @option{HANDLE}.
+Body is read from stdin and compressed. After receiving, remote side
+will execute specified @ref{CfgExec, handle} command with @option{ARG*}
+appended and decompressed body fed to command's stdin.
+
+For example, if remote side has following configuration file for your
+node:
+
+@verbatim
+exec: {
+ sendmail: [/usr/sbin/sendmail, "-t"]
+ appender: ["/bin/sh", "-c", "cat >> /append"]
+}
+@end verbatim
+
+then executing @verb{|echo My message | nncp-exec -replynice 123 REMOTE
+sendmail root@localhost|} will lead to execution of:
+
+@verbatim
+echo My message |
+ NNCP_SELF=REMOTE \
+ NNCP_SENDER=OurNodeId \
+ NNCP_NICE=123 \
+ /usr/sbin/sendmail -t root@localhost
+@end verbatim
+
+If @ref{CfgNotify, notification} is enabled on the remote side for exec
+handles, then it will sent simple letter after successful command
+execution with its output in message body.
@node nncp-file
@section nncp-file
@verbatim
-% nncp-file [options] SRC NODE:[DST]
+$ nncp-file [options] [-chunked INT] SRC NODE:[DST]
@end verbatim
-Send @code{SRC} file to remote @code{NODE}. @code{DST} specifies
-destination file name in remote's @ref{Configuration, incoming}
+Send @file{SRC} file to remote @option{NODE}. @file{DST} specifies
+destination file name in remote's @ref{CfgIncoming, incoming}
directory. If this file already exists there, then counter will be
appended to it.
(through the temporary file of course) -- so pay attention that sending
2 GiB file will create 2 GiB outbound encrypted packet.
-If @ref{Configuration, notification} is enabled on the remote side for
+If @file{SRC} equals to @file{-}, then create an encrypted temporary
+file and copy everything taken from stdin to it and use for outbound
+packet creation. Pay attention that if you want to send 1 GiB of data
+taken from stdin, then you have to have more than 2 GiB of disk space
+for that temporary file and resulting encrypted packet. You can control
+where temporary file will be stored using @env{TMPDIR} environment
+variable. Encryption is performed in AEAD mode with
+@url{https://cr.yp.to/chacha.html, ChaCha20}-@url{https://en.wikipedia.org/wiki/Poly1305, Poly1305}
+algorithms. Data is splitted on 128 KiB blocks. Each block is encrypted
+with increasing nonce counter.
+
+If @file{SRC} points to directory, then
+@url{https://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_01, pax archive}
+will be created on the fly with directory contents and destination
+filename @file{.tar} appended. It @strong{won't} contain any entities
+metainformation, but modification time with the names. UID/GID are set
+to zero. Directories have 777 permissions, files have 666, for being
+friendly with @command{umask}. Also each entity will have comment like
+@verb{|Autogenerated by NNCP version X.Y.Z built with goXXX|}.
+
+If @option{-chunked} is specified, then source file will be split
+@ref{Chunked, on chunks}. @option{INT} is the desired chunk size in
+KiBs. This mode is more CPU hungry. Pay attention that chunk is saved in
+spool directory immediately and it is not deleted if any error occurs.
+@option{-minsize} option is applied per each chunk. Do not forget about
+@ref{ChunkedZFS, possible} ZFS deduplication issues. Zero
+@option{-chunked} disables chunked transmission.
+
+If @ref{CfgNotify, notification} is enabled on the remote side for
file transmissions, then it will sent simple letter after successful
file receiving.
@section nncp-freq
@verbatim
-% nncp-freq [options] NODE:SRC DST
+$ nncp-freq [options] NODE:SRC [DST]
@end verbatim
-Send file request to @code{NODE}, asking it to send its @code{SRC} file
-from @ref{Configuration, freq} directory to our node under @code{DST}
-filename in our @ref{Configuration, incoming} one.
+Send file request to @option{NODE}, asking it to send its @file{SRC}
+file from @ref{CfgFreq, freq.path} directory to our node under @file{DST}
+filename in our @ref{CfgIncoming, incoming} one. If @file{DST} is not
+specified, then last element of @file{SRC} will be used.
-If @ref{Configuration, notification} is enabled on the remote side for
+If @ref{CfgNotify, notification} is enabled on the remote side for
file request, then it will sent simple letter after successful file
queuing.
@section nncp-log
@verbatim
-% nncp-log [options]
+$ nncp-log [options]
@end verbatim
Parse @ref{Log, log} file and print out its records in human-readable form.
-@node nncp-mail
-@section nncp-mail
-
-@verbatim
-% nncp-mail [options] NODE USER ...
-@end verbatim
-
-Send mail, that is read from stdin, to @code{NODE} and specified
-@code{USER}s. Mail message will be compressed. After receiving, remote
-side will execute specified @ref{Configuration, sendmail} command with
-@code{USER}s appended as a command line argument and feed decompressed
-mail body to that command's stdin.
-
-@node nncp-newnode
-@section nncp-newnode
-
-@verbatim
-% nncp-newnode [options] > mynewnode.yaml
-@end verbatim
-
-Generate new node: private keys, example configuration file and print it
-to stdout. You must use this command when you setup the new node.
-
-Pay attention that private keys generation consumes an entropy from your
-operating system.
-
@node nncp-pkt
@section nncp-pkt
@verbatim
-% nncp-pkt [options] < pkt
-% nncp-pkt [options] -dump < pkt > payload
+$ nncp-pkt [options] < pkt
+$ nncp-pkt [options] [-decompress] -dump < pkt > payload
+$ nncp-pkt -overheads
@end verbatim
Low level packet parser. Normally it should not be used, but can help in
Packet type: encrypted
Niceness: 64
Sender: 2WHBV3TPZHDOZGUJEH563ZEK7M33J4UESRFO4PDKWD5KZNPROABQ
-Payload size: 4.0 MiB (4162852 bytes)
@end verbatim
-If you specify @code{-dump} option and provide an @ref{Encrypted,
+If you specify @option{-dump} option and provide an @ref{Encrypted,
encrypted} packet, then it will verify and decrypt it to stdout.
Encrypted packets contain @ref{Plain, plain} ones, that also can be fed
-to @code{nncp-pkt}:
+to @command{nncp-pkt}:
@verbatim
Packet type: plain
Path: stargrave@stargrave.org
@end verbatim
-And with the @code{-dump} option it will give you the actual payload
-(the whole file, mail message, and so on).
+And with the @option{-dump} option it will give you the actual payload
+(the whole file, mail message, and so on). @option{-decompress} option
+tries to zstd-decompress the data from plain packet (useful for mail
+packets).
+
+@option{-overheads} options print encrypted, plain and size header overheads.
+
+@node nncp-reass
+@section nncp-reass
+
+@verbatim
+$ nncp-reass [options] [-dryrun] [-keep] [-dump] [-stdout] FILE.nncp.meta
+$ nncp-reass [options] [-dryrun] [-keep] {-all | -node NODE}
+@end verbatim
+
+Reassemble @ref{Chunked, chunked file} after @ref{nncp-toss, tossing}.
+
+When called with @option{FILE} option, this command will reassemble only
+it. When called with @option{-node} option, this command will try to
+reassemble all @file{.nncp.meta} files found in @option{NODE}'s
+@ref{CfgIncoming, incoming} directory. When called with @option{-all}
+option, then cycle through all known nodes to do the same.
+
+Reassembling process does the following:
+
+@enumerate
+@item Parses @ref{Chunked, @file{.nncp.meta}} file.
+@item Checks existence and size of every @file{.nncp.chunkXXX}.
+@item Verifies integrity of every chunk.
+@item Concatenates all chunks, simultaneously removing them from filesystem.
+@end enumerate
+
+That process reads the whole data twice. Be sure to have free disk
+space for at least one chunk. Decrypted chunk files as a rule are saved
+in pseudo-random order, so removing them during reassembly process will
+likely lead to filesystem fragmentation. Reassembly process on
+filesystems with deduplication capability should be rather lightweight.
+
+If @option{-dryrun} option is specified, then only existence and
+integrity checking are performed.
+
+If @option{-keep} option is specified, then no
+@file{.nncp.meta}/@file{.nncp.chunkXXX} files are deleted during
+reassembly process.
+
+@option{-stdout} option outputs reassembled file to stdout, instead of
+saving to temporary file with renaming after. This could be useful for
+reassembling on separate filesystem to lower fragmentation effect,
+and/or separate storage device for higher performance.
+
+@option{-dump} option prints meta-file contents in human-friendly form.
+It is useful mainly for debugging purposes. For example:
+@verbatim
+Original filename: testfile
+File size: 3.8 MiB (3987795 bytes)
+Chunk size: 1.0 MiB (1048576 bytes)
+Number of chunks: 4
+Checksums:
+ 0: eac60d819edf40b8ecdacd0b9a5a8c62de2d15eef3c8ca719eafa0be9b894017
+ 1: 013a07e659f2e353d0e4339c3375c96c7fffaa2fa00875635f440bbc4631052a
+ 2: f4f883975a663f2252328707a30e71b2678f933b2f3103db8475b03293e4316e
+ 3: 0e9e229501bf0ca42d4aa07393d19406d40b179f3922a3986ef12b41019b45a3
+@end verbatim
+
+ Do not forget about @ref{ChunkedZFS, possible} ZFS deduplication issues.
+
+@node nncp-rm
+@section nncp-rm
+
+@verbatim
+$ nncp-rm [options] -tmp
+$ nncp-rm [options] -lock
+$ nncp-rm [options] -node NODE -part
+$ nncp-rm [options] -node NODE -seen
+$ nncp-rm [options] -node NODE [-rx] [-tx]
+$ nncp-rm [options] -node NODE -pkt PKT
+@end verbatim
+
+This command is aimed to delete various files from your spool directory:
+
+@itemize
+@item If @option{-tmp} option is specified, then it will delete all
+temporary files in @file{spool/tmp} directory. Files may stay in it when
+commands like @ref{nncp-file} fail for some reason.
+@item If @option{-lock} option is specified, then all @file{.lock} files
+will be deleted in your spool directory.
+@item If @option{-pkt} option is specified, then @file{PKT} packet (its
+Base32 name) will be deleted. This is useful when you see some packet
+failing to be processed.
+@item When either @option{-rx} or @option{-tx} options are specified
+(maybe both of them), then delete all packets from that given queues. If
+@option{-part} is given, then delete only @file{.part}ly downloaded
+ones. If @option{-seen} option is specified, then delete only
+@file{.seen} files.
+@end itemize
@node nncp-stat
@section nncp-stat
@verbatim
-% nncp-stat [options]
+$ nncp-stat [options] [-node NODE]
@end verbatim
Print current @ref{Spool, spool} statistics about unsent and unprocessed
-packets. For each node and each niceness level there will be printed how
-many packets (with the total size) are in inbound (Rx) and outbound (Tx)
-queues.
+packets. For each node (unless @option{-node} specified) and each
+niceness level there will be printed how many packets (with the total
+size) are in inbound (Rx) and outbound (Tx) queues.
@node nncp-toss
@section nncp-toss
@verbatim
-% nncp-toss [options] [-dryrun]
+$ nncp-toss [options]
+ [-node NODE]
+ [-dryrun]
+ [-cycle INT]
+ [-seen]
+ [-nofile]
+ [-nofreq]
+ [-noexec]
+ [-notrns]
@end verbatim
Perform "tossing" operation on all inbound packets. This is the tool
copies files, sends mails, sends out file requests and relays transition
packets. It should be run after each online/offline exchange.
-@code{-dryrun} option does not perform any writing and sending, just
+@option{-dryrun} option does not perform any writing and sending, just
tells what it will do.
+@option{-cycle} option tells not to quit, but to repeat tossing every
+@option{INT} seconds in an infinite loop. That can be useful when
+running this command as a daemon.
+
+@option{-seen} option creates empty @file{XXX.seen} file after
+successful tossing of @file{XXX} packet. @ref{nncp-xfer},
+@ref{nncp-bundle}, @ref{nncp-daemon} and @ref{nncp-call} commands skip
+inbound packets that has been already seen, processed and tossed. This
+is helpful to prevent duplicates.
+
+@option{-nofile}, @option{-nofreq}, @option{-noexec}, @option{-notrns}
+options allow to disable any kind of packet types processing.
+
@node nncp-xfer
@section nncp-xfer
@verbatim
-% nncp-xfer [options] [-force] [-keep] [-rx|-tx] DIR
+$ nncp-xfer [options] [-node NODE] [-mkdir] [-keep] [-rx|-tx] DIR
@end verbatim
-Search for directory in @code{DIR} containing inbound packets for us and
+Search for directory in @file{DIR} containing inbound packets for us and
move them to local @ref{Spool, spool} directory. Also search for known
neighbours directories and move locally queued outbound packets to them.
This command is used for offline packets transmission.
-If @code{-force} option is specified, then outbound neighbour(s)
+If @option{-mkdir} option is specified, then outbound neighbour(s)
directories will be created. This is useful for the first time usage,
when storage device does not have any directories tree.
-If @code{-keep} option is specified, then keep copied files, do not
+If @option{-keep} option is specified, then keep copied files, do not
remove them.
-@code{-rx} option tells only to move inbound packets addressed to us.
-@code{-tx} option tells exactly the opposite: move only outbound packets.
+@option{-rx} option tells only to move inbound packets addressed to us.
+@option{-tx} option tells exactly the opposite: move only outbound packets.
+
+@ref{nncp-cfgmin} could be useful for creating stripped minimalistic
+configuration file version without any private keys.
+
+@file{DIR} directory has the following structure:
+@file{RECIPIENT/SENDER/PACKET}, where @file{RECIPIENT} is Base32 encoded
+destination node, @file{SENDER} is Base32 encoded sender node.
-@code{DIR} directory has the following structure:
-@code{RECIPIENT/SENDER/PACKET}, where @code{RECIPIENT} is Base32 encoded
-destination node, @code{SENDER} is Base32 encoded sender node.
+Also look for @ref{nncp-bundle}, especially if you deal with CD-ROM and
+tape drives.