Check the error return of flush_write_file().
[rsync/rsync.git] / rsync.yo
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1mailto(rsync-bugs@samba.org)
2manpage(rsync)(1)(30 Apr 2004)()()
3manpagename(rsync)(faster, flexible replacement for rcp)
4manpagesynopsis()
5
6rsync [OPTION]... SRC [SRC]... [USER@]HOST:DEST
7
8rsync [OPTION]... [USER@]HOST:SRC DEST
9
10rsync [OPTION]... SRC [SRC]... DEST
11
12rsync [OPTION]... [USER@]HOST::SRC [DEST]
13
14rsync [OPTION]... SRC [SRC]... [USER@]HOST::DEST
15
16rsync [OPTION]... rsync://[USER@]HOST[:PORT]/SRC [DEST]
17
18rsync [OPTION]... SRC [SRC]... rsync://[USER@]HOST[:PORT]/DEST
19
20manpagedescription()
21
22rsync is a program that behaves in much the same way that rcp does,
23but has many more options and uses the rsync remote-update protocol to
24greatly speed up file transfers when the destination file already
25exists.
26
27The rsync remote-update protocol allows rsync to transfer just the
28differences between two sets of files across the network connection, using
29an efficient checksum-search algorithm described in the technical
30report that accompanies this package.
31
32Some of the additional features of rsync are:
33
34itemize(
35 it() support for copying links, devices, owners, groups, and permissions
36 it() exclude and exclude-from options similar to GNU tar
37 it() a CVS exclude mode for ignoring the same files that CVS would ignore
38 it() can use any transparent remote shell, including ssh or rsh
39 it() does not require root privileges
40 it() pipelining of file transfers to minimize latency costs
41 it() support for anonymous or authenticated rsync servers (ideal for
42 mirroring)
43)
44
45manpagesection(GENERAL)
46
47There are eight different ways of using rsync. They are:
48
49itemize(
50 it() for copying local files. This is invoked when neither
51 source nor destination path contains a : separator
52
53 it() for copying from the local machine to a remote machine using
54 a remote shell program as the transport (such as ssh or
55 rsh). This is invoked when the destination path contains a
56 single : separator.
57
58 it() for copying from a remote machine to the local machine
59 using a remote shell program. This is invoked when the source
60 contains a : separator.
61
62 it() for copying from a remote rsync server to the local
63 machine. This is invoked when the source path contains a ::
64 separator or an rsync:// URL.
65
66 it() for copying from the local machine to a remote rsync
67 server. This is invoked when the destination path contains a ::
68 separator or an rsync:// URL.
69
70 it() for copying from a remote machine using a remote shell
71 program as the transport, using rsync server on the remote
72 machine. This is invoked when the source path contains a ::
73 separator and the --rsh=COMMAND (aka "-e COMMAND") option is
74 also provided.
75
76 it() for copying from the local machine to a remote machine
77 using a remote shell program as the transport, using rsync
78 server on the remote machine. This is invoked when the
79 destination path contains a :: separator and the
80 --rsh=COMMAND option is also provided.
81
82 it() for listing files on a remote machine. This is done the
83 same way as rsync transfers except that you leave off the
84 local destination.
85)
86
87Note that in all cases (other than listing) at least one of the source
88and destination paths must be local.
89
90manpagesection(SETUP)
91
92See the file README for installation instructions.
93
94Once installed, you can use rsync to any machine that you can access via
95a remote shell (as well as some that you can access using the rsync
96daemon-mode protocol). For remote transfers, a modern rsync uses ssh
97for its communications, but it may have been configured to use a
98different remote shell by default, such as rsh or remsh.
99
100You can also specify any remote shell you like, either by using the -e
101command line option, or by setting the RSYNC_RSH environment variable.
102
103One common substitute is to use ssh, which offers a high degree of
104security.
105
106Note that rsync must be installed on both the source and destination
107machines.
108
109manpagesection(USAGE)
110
111You use rsync in the same way you use rcp. You must specify a source
112and a destination, one of which may be remote.
113
114Perhaps the best way to explain the syntax is with some examples:
115
116quote(rsync *.c foo:src/)
117
118This would transfer all files matching the pattern *.c from the
119current directory to the directory src on the machine foo. If any of
120the files already exist on the remote system then the rsync
121remote-update protocol is used to update the file by sending only the
122differences. See the tech report for details.
123
124quote(rsync -avz foo:src/bar /data/tmp)
125
126This would recursively transfer all files from the directory src/bar on the
127machine foo into the /data/tmp/bar directory on the local machine. The
128files are transferred in "archive" mode, which ensures that symbolic
129links, devices, attributes, permissions, ownerships, etc. are preserved
130in the transfer. Additionally, compression will be used to reduce the
131size of data portions of the transfer.
132
133quote(rsync -avz foo:src/bar/ /data/tmp)
134
135A trailing slash on the source changes this behavior to avoid creating an
136additional directory level at the destination. You can think of a trailing
137/ on a source as meaning "copy the contents of this directory" as opposed
138to "copy the directory by name", but in both cases the attributes of the
139containing directory are transferred to the containing directory on the
140destination. In other words, each of the following commands copies the
141files in the same way, including their setting of the attributes of
142/dest/foo:
143
144quote(rsync -avz /src/foo /dest)
145quote(rsync -avz /src/foo/ /dest/foo)
146
147You can also use rsync in local-only mode, where both the source and
148destination don't have a ':' in the name. In this case it behaves like
149an improved copy command.
150
151quote(rsync somehost.mydomain.com::)
152
153This would list all the anonymous rsync modules available on the host
154somehost.mydomain.com. (See the following section for more details.)
155
156
157manpagesection(CONNECTING TO AN RSYNC SERVER)
158
159It is also possible to use rsync without a remote shell as the
160transport. In this case you will connect to a remote rsync server
161running on TCP port 873.
162
163You may establish the connection via a web proxy by setting the
164environment variable RSYNC_PROXY to a hostname:port pair pointing to
165your web proxy. Note that your web proxy's configuration must support
166proxy connections to port 873.
167
168Using rsync in this way is the same as using it with a remote shell except
169that:
170
171itemize(
172 it() you use a double colon :: instead of a single colon to
173 separate the hostname from the path or an rsync:// URL.
174
175 it() the remote server may print a message of the day when you
176 connect.
177
178 it() if you specify no path name on the remote server then the
179 list of accessible paths on the server will be shown.
180
181 it() if you specify no local destination then a listing of the
182 specified files on the remote server is provided.
183)
184
185Some paths on the remote server may require authentication. If so then
186you will receive a password prompt when you connect. You can avoid the
187password prompt by setting the environment variable RSYNC_PASSWORD to
188the password you want to use or using the --password-file option. This
189may be useful when scripting rsync.
190
191WARNING: On some systems environment variables are visible to all
192users. On those systems using --password-file is recommended.
193
194manpagesection(CONNECTING TO AN RSYNC SERVER OVER A REMOTE SHELL PROGRAM)
195
196It is sometimes useful to be able to set up file transfers using rsync
197server capabilities on the remote machine, while still using ssh or
198rsh for transport. This is especially useful when you want to connect
199to a remote machine via ssh (for encryption or to get through a
200firewall), but you still want to have access to the rsync server
201features (see RUNNING AN RSYNC SERVER OVER A REMOTE SHELL PROGRAM,
202below).
203
204From the user's perspective, using rsync in this way is the same as
205using it to connect to an rsync server, except that you must
206explicitly set the remote shell program on the command line with
207--rsh=COMMAND. (Setting RSYNC_RSH in the environment will not turn on
208this functionality.)
209
210In order to distinguish between the remote-shell user and the rsync
211server user, you can use '-l user' on your remote-shell command:
212
213quote(rsync -av --rsh="ssh -l ssh-user" rsync-user@host::module[/path] local-path)
214
215The "ssh-user" will be used at the ssh level; the "rsync-user" will be
216used to check against the rsyncd.conf on the remote host.
217
218manpagesection(RUNNING AN RSYNC SERVER)
219
220An rsync server is configured using a configuration file. Please see the
221rsyncd.conf(5) man page for more information. By default the configuration
222file is called /etc/rsyncd.conf, unless rsync is running over a remote
223shell program and is not running as root; in that case, the default name
224is rsyncd.conf in the current directory on the remote computer
225(typically $HOME).
226
227manpagesection(RUNNING AN RSYNC SERVER OVER A REMOTE SHELL PROGRAM)
228
229See the rsyncd.conf(5) man page for full information on the rsync
230server configuration file.
231
232Several configuration options will not be available unless the remote
233user is root (e.g. chroot, setuid/setgid, etc.). There is no need to
234configure inetd or the services map to include the rsync server port
235if you run an rsync server only via a remote shell program.
236
237To run an rsync server out of a single-use ssh key, see this section
238in the rsyncd.conf(5) man page.
239
240manpagesection(EXAMPLES)
241
242Here are some examples of how I use rsync.
243
244To backup my wife's home directory, which consists of large MS Word
245files and mail folders, I use a cron job that runs
246
247quote(rsync -Cavz . arvidsjaur:backup)
248
249each night over a PPP connection to a duplicate directory on my machine
250"arvidsjaur".
251
252To synchronize my samba source trees I use the following Makefile
253targets:
254
255quote( get:nl()
256 rsync -avuzb --exclude '*~' samba:samba/ .
257
258 put:nl()
259 rsync -Cavuzb . samba:samba/
260
261 sync: get put)
262
263this allows me to sync with a CVS directory at the other end of the
264connection. I then do cvs operations on the remote machine, which saves a
265lot of time as the remote cvs protocol isn't very efficient.
266
267I mirror a directory between my "old" and "new" ftp sites with the
268command
269
270quote(rsync -az -e ssh --delete ~ftp/pub/samba/ nimbus:"~ftp/pub/tridge/samba")
271
272this is launched from cron every few hours.
273
274manpagesection(OPTIONS SUMMARY)
275
276Here is a short summary of the options available in rsync. Please refer
277to the detailed description below for a complete description.
278
279verb(
280 -v, --verbose increase verbosity
281 -q, --quiet decrease verbosity
282 -c, --checksum always checksum
283 -a, --archive archive mode, equivalent to -rlptgoD
284 -r, --recursive recurse into directories
285 -R, --relative use relative path names
286 --no-relative turn off --relative
287 --no-implied-dirs don't send implied dirs with -R
288 -b, --backup make backups (see --suffix & --backup-dir)
289 --backup-dir make backups into this directory
290 --suffix=SUFFIX backup suffix (default ~ w/o --backup-dir)
291 -u, --update update only (don't overwrite newer files)
292 --inplace update the destination files inplace
293 -K, --keep-dirlinks treat symlinked dir on receiver as dir
294 -l, --links copy symlinks as symlinks
295 -L, --copy-links copy the referent of all symlinks
296 --copy-unsafe-links copy the referent of "unsafe" symlinks
297 --safe-links ignore "unsafe" symlinks
298 -H, --hard-links preserve hard links
299 -p, --perms preserve permissions
300 -o, --owner preserve owner (root only)
301 -g, --group preserve group
302 -D, --devices preserve devices (root only)
303 -t, --times preserve times
304 -S, --sparse handle sparse files efficiently
305 -n, --dry-run show what would have been transferred
306 -W, --whole-file copy whole files, no incremental checks
307 --no-whole-file turn off --whole-file
308 -x, --one-file-system don't cross filesystem boundaries
309 -B, --block-size=SIZE checksum blocking size (default 700)
310 -e, --rsh=COMMAND specify the remote shell
311 --rsync-path=PATH specify path to rsync on the remote machine
312 --existing only update files that already exist
313 --ignore-existing ignore files that already exist on receiver
314 --delete delete files that don't exist on sender
315 --delete-excluded also delete excluded files on receiver
316 --delete-after receiver deletes after transfer, not before
317 --ignore-errors delete even if there are I/O errors
318 --max-delete=NUM don't delete more than NUM files
319 --partial keep partially transferred files
320 --force force deletion of dirs even if not empty
321 --numeric-ids don't map uid/gid values by user/group name
322 --timeout=TIME set I/O timeout in seconds
323 -I, --ignore-times turn off mod time & file size quick check
324 --size-only ignore mod time for quick check (use size)
325 --modify-window=NUM compare mod times with reduced accuracy
326 -T --temp-dir=DIR create temporary files in directory DIR
327 --compare-dest=DIR also compare received files relative to DIR
328 --link-dest=DIR create hardlinks to DIR for unchanged files
329 -P equivalent to --partial --progress
330 -z, --compress compress file data
331 -C, --cvs-exclude auto ignore files in the same way CVS does
332 --exclude=PATTERN exclude files matching PATTERN
333 --exclude-from=FILE exclude patterns listed in FILE
334 --include=PATTERN don't exclude files matching PATTERN
335 --include-from=FILE don't exclude patterns listed in FILE
336 --files-from=FILE read FILE for list of source-file names
337 -0 --from0 all file lists are delimited by nulls
338 --version print version number
339 --daemon run as an rsync daemon
340 --no-detach do not detach from the parent
341 --address=ADDRESS bind to the specified address
342 --config=FILE specify alternate rsyncd.conf file
343 --port=PORT specify alternate rsyncd port number
344 --blocking-io use blocking I/O for the remote shell
345 --no-blocking-io turn off --blocking-io
346 --stats give some file transfer stats
347 --progress show progress during transfer
348 --log-format=FORMAT log file transfers using specified format
349 --password-file=FILE get password from FILE
350 --bwlimit=KBPS limit I/O bandwidth, KBytes per second
351 --write-batch=FILE write a batch to FILE
352 --read-batch=FILE read a batch from FILE
353 --checksum-seed=NUM set block/file checksum seed
354 -4 --ipv4 prefer IPv4
355 -6 --ipv6 prefer IPv6
356 -h, --help show this help screen
357
358
359)
360
361manpageoptions()
362
363rsync uses the GNU long options package. Many of the command line
364options have two variants, one short and one long. These are shown
365below, separated by commas. Some options only have a long variant.
366The '=' for options that take a parameter is optional; whitespace
367can be used instead.
368
369startdit()
370dit(bf(-h, --help)) Print a short help page describing the options
371available in rsync
372
373dit(bf(--version)) print the rsync version number and exit
374
375dit(bf(-v, --verbose)) This option increases the amount of information you
376are given during the transfer. By default, rsync works silently. A
377single -v will give you information about what files are being
378transferred and a brief summary at the end. Two -v flags will give you
379information on what files are being skipped and slightly more
380information at the end. More than two -v flags should only be used if
381you are debugging rsync.
382
383dit(bf(-q, --quiet)) This option decreases the amount of information you
384are given during the transfer, notably suppressing information messages
385from the remote server. This flag is useful when invoking rsync from
386cron.
387
388dit(bf(-I, --ignore-times)) Normally rsync will skip any files that are
389already the same size and have the same modification time-stamp.
390This option turns off this "quick check" behavior.
391
392dit(bf(--size-only)) Normally rsync will not transfer any files that are
393already the same size and have the same modification time-stamp. With the
394--size-only option, files will not be transferred if they have the same size,
395regardless of timestamp. This is useful when starting to use rsync
396after using another mirroring system which may not preserve timestamps
397exactly.
398
399dit(bf(--modify-window)) When comparing two timestamps rsync treats
400the timestamps as being equal if they are within the value of
401modify_window. This is normally zero, but you may find it useful to
402set this to a larger value in some situations. In particular, when
403transferring to Windows FAT filesystems which cannot represent times
404with a 1 second resolution --modify-window=1 is useful.
405
406dit(bf(-c, --checksum)) This forces the sender to checksum all files using
407a 128-bit MD4 checksum before transfer. The checksum is then
408explicitly checked on the receiver and any files of the same name
409which already exist and have the same checksum and size on the
410receiver are not transferred. This option can be quite slow.
411
412dit(bf(-a, --archive)) This is equivalent to -rlptgoD. It is a quick
413way of saying you want recursion and want to preserve almost
414everything.
415
416Note however that bf(-a) bf(does not preserve hardlinks), because
417finding multiply-linked files is expensive. You must separately
418specify bf(-H).
419
420dit(bf(-r, --recursive)) This tells rsync to copy directories
421recursively. If you don't specify this then rsync won't copy
422directories at all.
423
424dit(bf(-R, --relative)) Use relative paths. This means that the full path
425names specified on the command line are sent to the server rather than
426just the last parts of the filenames. This is particularly useful when
427you want to send several different directories at the same time. For
428example, if you used the command
429
430verb(rsync foo/bar/foo.c remote:/tmp/)
431
432then this would create a file called foo.c in /tmp/ on the remote
433machine. If instead you used
434
435verb(rsync -R foo/bar/foo.c remote:/tmp/)
436
437then a file called /tmp/foo/bar/foo.c would be created on the remote
438machine -- the full path name is preserved.
439
440dit(bf(--no-relative)) Turn off the --relative option. This is only
441needed if you want to use --files-from without its implied --relative
442file processing.
443
444dit(bf(--no-implied-dirs)) When combined with the --relative option, the
445implied directories in each path are not explicitly duplicated as part
446of the transfer. This makes the transfer more optimal and also allows
447the two sides to have non-matching symlinks in the implied part of the
448path. For instance, if you transfer the file "/path/foo/file" with -R,
449the default is for rsync to ensure that "/path" and "/path/foo" on the
450destination exactly match the directories/symlinks of the source. Using
451the --no-implied-dirs option would omit both of these implied dirs,
452which means that if "/path" was a real directory on one machine and a
453symlink of the other machine, rsync would not try to change this.
454
455dit(bf(-b, --backup)) With this option, preexisting destination files are
456renamed as each file is transferred or deleted. You can control where the
457backup file goes and what (if any) suffix gets appended using the
458--backup-dir and --suffix options.
459
460dit(bf(--backup-dir=DIR)) In combination with the --backup option, this
461tells rsync to store all backups in the specified directory. This is
462very useful for incremental backups. You can additionally
463specify a backup suffix using the --suffix option
464(otherwise the files backed up in the specified directory
465will keep their original filenames).
466If DIR is a relative path, it is relative to the destination directory
467(which changes in a recursive transfer).
468
469dit(bf(--suffix=SUFFIX)) This option allows you to override the default
470backup suffix used with the --backup (-b) option. The default suffix is a ~
471if no --backup-dir was specified, otherwise it is an empty string.
472
473dit(bf(-u, --update)) This forces rsync to skip any files for which the
474destination file already exists and has a date later than the source
475file.
476
477In the currently implementation, a difference of file format is always
478considered to be important enough for an update, no matter what date
479is on the objects. In other words, if the source has a directory or a
480symlink where the destination has a file, the transfer would occur
481regardless of the timestamps. This might change in the future (feel
482free to comment on this on the mailing list if you have an opinion).
483
484dit(bf(-K, --keep-dirlinks)) On the receiving side, if a symlink is
485pointing to a directory, it will be treated as matching a directory
486from the sender.
487
488dit(bf(--inplace)) This causes rsync not to create a new copy of the file
489and then move it into place. Instead rsync will overwrite the existing
490file, meaning that the rsync algorithm can't extract the full amount of
491network reduction it might otherwise.
492
493This option is useful for transfer of large files with block-based change
494or appended data, and also on systems that are disk bound not network bound.
495
496WARNING: The file's data will be in an inconsistent state during the
497transfer (and possibly afterward if the transfer gets interrupted), so you
498should not use this option to update files that are in use. Also note that
499rsync will be unable to update a file inplace that is not writable by the
500receiving user.
501
502dit(bf(-l, --links)) When symlinks are encountered, recreate the
503symlink on the destination.
504
505dit(bf(-L, --copy-links)) When symlinks are encountered, the file that
506they point to (the referent) is copied, rather than the symlink.
507
508dit(bf(--copy-unsafe-links)) This tells rsync to copy the referent of
509symbolic links that point outside the copied tree. Absolute symlinks
510are also treated like ordinary files, and so are any symlinks in the
511source path itself when --relative is used.
512
513dit(bf(--safe-links)) This tells rsync to ignore any symbolic links
514which point outside the copied tree. All absolute symlinks are
515also ignored. Using this option in conjunction with --relative may
516give unexpected results.
517
518dit(bf(-H, --hard-links)) This tells rsync to recreate hard links on
519the remote system to be the same as the local system. Without this
520option hard links are treated like regular files.
521
522Note that rsync can only detect hard links if both parts of the link
523are in the list of files being sent.
524
525This option can be quite slow, so only use it if you need it.
526
527dit(bf(-W, --whole-file)) With this option the incremental rsync algorithm
528is not used and the whole file is sent as-is instead. The transfer may be
529faster if this option is used when the bandwidth between the source and
530destination machines is higher than the bandwidth to disk (especially when the
531"disk" is actually a networked filesystem). This is the default when both
532the source and destination are specified as local paths.
533
534dit(bf(--no-whole-file)) Turn off --whole-file, for use when it is the
535default.
536
537dit(bf(-p, --perms)) This option causes rsync to set the destination
538permissions to be the same as the source permissions.
539
540Without this option, each new file gets its permissions set based on the
541source file's permissions and the umask at the receiving end, while all
542other files (including updated files) retain their existing permissions
543(which is the same behavior as other file-copy utilities, such as cp).
544
545dit(bf(-o, --owner)) This option causes rsync to set the owner of the
546destination file to be the same as the source file. On most systems,
547only the super-user can set file ownership. By default, the preservation
548is done by name, but may fall back to using the ID number in some
549circumstances. See the --numeric-ids option for a full discussion.
550
551dit(bf(-g, --group)) This option causes rsync to set the group of the
552destination file to be the same as the source file. If the receiving
553program is not running as the super-user, only groups that the
554receiver is a member of will be preserved. By default, the preservation
555is done by name, but may fall back to using the ID number in some
556circumstances. See the --numeric-ids option for a full discussion.
557
558dit(bf(-D, --devices)) This option causes rsync to transfer character and
559block device information to the remote system to recreate these
560devices. This option is only available to the super-user.
561
562dit(bf(-t, --times)) This tells rsync to transfer modification times along
563with the files and update them on the remote system. Note that if this
564option is not used, the optimization that excludes files that have not been
565modified cannot be effective; in other words, a missing -t or -a will
566cause the next transfer to behave as if it used -I, and all files will have
567their checksums compared and show up in log messages even if they haven't
568changed.
569
570dit(bf(-n, --dry-run)) This tells rsync to not do any file transfers,
571instead it will just report the actions it would have taken.
572
573dit(bf(-S, --sparse)) Try to handle sparse files efficiently so they take
574up less space on the destination.
575
576NOTE: Don't use this option when the destination is a Solaris "tmpfs"
577filesystem. It doesn't seem to handle seeks over null regions
578correctly and ends up corrupting the files.
579
580dit(bf(-x, --one-file-system)) This tells rsync not to cross filesystem
581boundaries when recursing. This is useful for transferring the
582contents of only one filesystem.
583
584dit(bf(--existing)) This tells rsync not to create any new files -
585only update files that already exist on the destination.
586
587dit(bf(--ignore-existing))
588This tells rsync not to update files that already exist on
589the destination.
590
591dit(bf(--max-delete=NUM)) This tells rsync not to delete more than NUM
592files or directories. This is useful when mirroring very large trees
593to prevent disasters.
594
595dit(bf(--delete)) This tells rsync to delete any files on the receiving
596side that aren't on the sending side. Files that are excluded from
597transfer are excluded from being deleted unless you use --delete-excluded.
598
599This option has no effect if directory recursion is not selected.
600
601This option can be dangerous if used incorrectly! It is a very good idea
602to run first using the dry run option (-n) to see what files would be
603deleted to make sure important files aren't listed.
604
605If the sending side detects any I/O errors then the deletion of any
606files at the destination will be automatically disabled. This is to
607prevent temporary filesystem failures (such as NFS errors) on the
608sending side causing a massive deletion of files on the
609destination. You can override this with the --ignore-errors option.
610
611dit(bf(--delete-excluded)) In addition to deleting the files on the
612receiving side that are not on the sending side, this tells rsync to also
613delete any files on the receiving side that are excluded (see --exclude).
614Implies --delete.
615
616dit(bf(--delete-after)) By default rsync does file deletions on the
617receiving side before transferring files to try to ensure that there is
618sufficient space on the receiving filesystem. If you want to delete
619after transferring, use the --delete-after switch. Implies --delete.
620
621dit(bf(--ignore-errors)) Tells --delete to go ahead and delete files
622even when there are I/O errors.
623
624dit(bf(--force)) This options tells rsync to delete directories even if
625they are not empty when they are to be replaced by non-directories. This
626is only relevant without --delete because deletions are now done depth-first.
627Requires the --recursive option (which is implied by -a) to have any effect.
628
629dit(bf(-B, --block-size=BLOCKSIZE)) This controls the block size used in
630the rsync algorithm. See the technical report for details.
631
632dit(bf(-e, --rsh=COMMAND)) This option allows you to choose an alternative
633remote shell program to use for communication between the local and
634remote copies of rsync. Typically, rsync is configured to use ssh by
635default, but you may prefer to use rsh on a local network.
636
637If this option is used with bf([user@]host::module/path), then the
638remote shell em(COMMAND) will be used to run an rsync server on the
639remote host, and all data will be transmitted through that remote
640shell connection, rather than through a direct socket connection to a
641running rsync server on the remote host. See the section "CONNECTING
642TO AN RSYNC SERVER OVER A REMOTE SHELL PROGRAM" above.
643
644Command-line arguments are permitted in COMMAND provided that COMMAND is
645presented to rsync as a single argument. For example:
646
647quote(-e "ssh -p 2234")
648
649(Note that ssh users can alternately customize site-specific connect
650options in their .ssh/config file.)
651
652You can also choose the remote shell program using the RSYNC_RSH
653environment variable, which accepts the same range of values as -e.
654
655See also the --blocking-io option which is affected by this option.
656
657dit(bf(--rsync-path=PATH)) Use this to specify the path to the copy of
658rsync on the remote machine. Useful when it's not in your path. Note
659that this is the full path to the binary, not just the directory that
660the binary is in.
661
662dit(bf(-C, --cvs-exclude)) This is a useful shorthand for excluding a
663broad range of files that you often don't want to transfer between
664systems. It uses the same algorithm that CVS uses to determine if
665a file should be ignored.
666
667The exclude list is initialized to:
668
669quote(RCS SCCS CVS CVS.adm RCSLOG cvslog.* tags TAGS .make.state
670.nse_depinfo *~ #* .#* ,* _$* *$ *.old *.bak *.BAK *.orig *.rej
671.del-* *.a *.olb *.o *.obj *.so *.exe *.Z *.elc *.ln core .svn/)
672
673then files listed in a $HOME/.cvsignore are added to the list and any
674files listed in the CVSIGNORE environment variable (all cvsignore names
675are delimited by whitespace).
676
677Finally, any file is ignored if it is in the same directory as a
678.cvsignore file and matches one of the patterns listed therein.
679See the bf(cvs(1)) manual for more information.
680
681dit(bf(--exclude=PATTERN)) This option allows you to selectively exclude
682certain files from the list of files to be transferred. This is most
683useful in combination with a recursive transfer.
684
685You may use as many --exclude options on the command line as you like
686to build up the list of files to exclude.
687
688See the EXCLUDE PATTERNS section for detailed information on this option.
689
690dit(bf(--exclude-from=FILE)) This option is similar to the --exclude
691option, but instead it adds all exclude patterns listed in the file
692FILE to the exclude list. Blank lines in FILE and lines starting with
693';' or '#' are ignored.
694If em(FILE) is bf(-) the list will be read from standard input.
695
696dit(bf(--include=PATTERN)) This option tells rsync to not exclude the
697specified pattern of filenames. This is useful as it allows you to
698build up quite complex exclude/include rules.
699
700See the EXCLUDE PATTERNS section for detailed information on this option.
701
702dit(bf(--include-from=FILE)) This specifies a list of include patterns
703from a file.
704If em(FILE) is "-" the list will be read from standard input.
705
706dit(bf(--files-from=FILE)) Using this option allows you to specify the
707exact list of files to transfer (as read from the specified FILE or "-"
708for standard input). It also tweaks the default behavior of rsync to make
709transferring just the specified files and directories easier. For
710instance, the --relative option is enabled by default when this option
711is used (use --no-relative if you want to turn that off), all
712directories specified in the list are created on the destination (rather
713than being noisily skipped without -r), and the -a (--archive) option's
714behavior does not imply -r (--recursive) -- specify it explicitly, if
715you want it.
716
717The file names that are read from the FILE are all relative to the
718source dir -- any leading slashes are removed and no ".." references are
719allowed to go higher than the source dir. For example, take this
720command:
721
722quote(rsync -a --files-from=/tmp/foo /usr remote:/backup)
723
724If /tmp/foo contains the string "bin" (or even "/bin"), the /usr/bin
725directory will be created as /backup/bin on the remote host (but the
726contents of the /usr/bin dir would not be sent unless you specified -r
727or the names were explicitly listed in /tmp/foo). Also keep in mind
728that the effect of the (enabled by default) --relative option is to
729duplicate only the path info that is read from the file -- it does not
730force the duplication of the source-spec path (/usr in this case).
731
732In addition, the --files-from file can be read from the remote host
733instead of the local host if you specify a "host:" in front of the file
734(the host must match one end of the transfer). As a short-cut, you can
735specify just a prefix of ":" to mean "use the remote end of the
736transfer". For example:
737
738quote(rsync -a --files-from=:/path/file-list src:/ /tmp/copy)
739
740This would copy all the files specified in the /path/file-list file that
741was located on the remote "src" host.
742
743dit(bf(-0, --from0)) This tells rsync that the filenames it reads from a
744file are terminated by a null ('\0') character, not a NL, CR, or CR+LF.
745This affects --exclude-from, --include-from, and --files-from.
746It does not affect --cvs-exclude (since all names read from a .cvsignore
747file are split on whitespace).
748
749dit(bf(-T, --temp-dir=DIR)) This option instructs rsync to use DIR as a
750scratch directory when creating temporary copies of the files
751transferred on the receiving side. The default behavior is to create
752the temporary files in the receiving directory.
753
754dit(bf(--compare-dest=DIR)) This option instructs rsync to use DIR on
755the destination machine as an additional directory to compare destination
756files against when doing transfers if the files are missing in the
757destination directory. This is useful for doing transfers to a new
758destination while leaving existing files intact, and then doing a
759flash-cutover when all files have been successfully transferred (for
760example by moving directories around and removing the old directory,
761although this skips files that haven't changed; see also --link-dest).
762This option increases the usefulness of --partial because partially
763transferred files will remain in the new temporary destination until they
764have a chance to be completed. If DIR is a relative path, it is relative
765to the destination directory (which changes in a recursive transfer).
766
767dit(bf(--link-dest=DIR)) This option behaves like bf(--compare-dest) but
768also will create hard links from em(DIR) to the destination directory for
769unchanged files. Files with changed ownership or permissions will not be
770linked.
771Like bf(--compare-dest) if DIR is a relative path, it is relative
772to the destination directory (which changes in a recursive transfer).
773An example:
774
775verb(
776 rsync -av --link-dest=$PWD/prior_dir host:src_dir/ new_dir/
777)
778
779dit(bf(-z, --compress)) With this option, rsync compresses any data from
780the files that it sends to the destination machine. This
781option is useful on slow connections. The compression method used is the
782same method that gzip uses.
783
784Note this this option typically achieves better compression ratios
785that can be achieved by using a compressing remote shell, or a
786compressing transport, as it takes advantage of the implicit
787information sent for matching data blocks.
788
789dit(bf(--numeric-ids)) With this option rsync will transfer numeric group
790and user IDs rather than using user and group names and mapping them
791at both ends.
792
793By default rsync will use the username and groupname to determine
794what ownership to give files. The special uid 0 and the special group
7950 are never mapped via user/group names even if the --numeric-ids
796option is not specified.
797
798If a user or group has no name on the source system or it has no match
799on the destination system, then the numeric ID
800from the source system is used instead. See also the comments on the
801"use chroot" setting in the rsyncd.conf manpage for information on how
802the chroot setting affects rsync's ability to look up the names of the
803users and groups and what you can do about it.
804
805dit(bf(--timeout=TIMEOUT)) This option allows you to set a maximum I/O
806timeout in seconds. If no data is transferred for the specified time
807then rsync will exit. The default is 0, which means no timeout.
808
809dit(bf(--daemon)) This tells rsync that it is to run as a daemon. The
810daemon may be accessed using the bf(host::module) or
811bf(rsync://host/module/) syntax.
812
813If standard input is a socket then rsync will assume that it is being
814run via inetd, otherwise it will detach from the current terminal and
815become a background daemon. The daemon will read the config file
816(rsyncd.conf) on each connect made by a client and respond to
817requests accordingly. See the rsyncd.conf(5) man page for more
818details.
819
820dit(bf(--no-detach)) When running as a daemon, this option instructs
821rsync to not detach itself and become a background process. This
822option is required when running as a service on Cygwin, and may also
823be useful when rsync is supervised by a program such as
824bf(daemontools) or AIX's bf(System Resource Controller).
825bf(--no-detach) is also recommended when rsync is run under a
826debugger. This option has no effect if rsync is run from inetd or
827sshd.
828
829dit(bf(--address)) By default rsync will bind to the wildcard address
830when run as a daemon with the --daemon option or when connecting to a
831rsync server. The --address option allows you to specify a specific IP
832address (or hostname) to bind to. This makes virtual hosting possible
833in conjunction with the --config option.
834
835dit(bf(--config=FILE)) This specifies an alternate config file than
836the default. This is only relevant when --daemon is specified.
837The default is /etc/rsyncd.conf unless the daemon is running over
838a remote shell program and the remote user is not root; in that case
839the default is rsyncd.conf in the current directory (typically $HOME).
840
841dit(bf(--port=PORT)) This specifies an alternate TCP port number to use
842rather than the default port 873.
843
844dit(bf(--blocking-io)) This tells rsync to use blocking I/O when launching
845a remote shell transport. If the remote shell is either rsh or remsh,
846rsync defaults to using
847blocking I/O, otherwise it defaults to using non-blocking I/O. (Note that
848ssh prefers non-blocking I/O.)
849
850dit(bf(--no-blocking-io)) Turn off --blocking-io, for use when it is the
851default.
852
853dit(bf(--log-format=FORMAT)) This allows you to specify exactly what the
854rsync client logs to stdout on a per-file basis. The log format is
855specified using the same format conventions as the log format option in
856rsyncd.conf.
857
858dit(bf(--stats)) This tells rsync to print a verbose set of statistics
859on the file transfer, allowing you to tell how effective the rsync
860algorithm is for your data.
861
862dit(bf(--partial)) By default, rsync will delete any partially
863transferred file if the transfer is interrupted. In some circumstances
864it is more desirable to keep partially transferred files. Using the
865--partial option tells rsync to keep the partial file which should
866make a subsequent transfer of the rest of the file much faster.
867
868dit(bf(--progress)) This option tells rsync to print information
869showing the progress of the transfer. This gives a bored user
870something to watch.
871Implies --verbose without incrementing verbosity.
872
873When the file is transferring, the data looks like this:
874
875verb(
876 782448 63% 110.64kB/s 0:00:04
877)
878
879This tells you the current file size, the percentage of the transfer that
880is complete, the current calculated file-completion rate (including both
881data over the wire and data being matched locally), and the estimated time
882remaining in this transfer.
883
884After the a file is complete, it the data looks like this:
885
886verb(
887 1238099 100% 146.38kB/s 0:00:08 (5, 57.1% of 396)
888)
889
890This tells you the final file size, that it's 100% complete, the final
891transfer rate for the file, the amount of elapsed time it took to transfer
892the file, and the addition of a total-transfer summary in parentheses.
893These additional numbers tell you how many files have been updated, and
894what percent of the total number of files has been scanned.
895
896dit(bf(-P)) The -P option is equivalent to --partial --progress. I
897found myself typing that combination quite often so I created an
898option to make it easier.
899
900dit(bf(--password-file)) This option allows you to provide a password
901in a file for accessing a remote rsync server. Note that this option
902is only useful when accessing an rsync server using the built in
903transport, not when using a remote shell as the transport. The file
904must not be world readable. It should contain just the password as a
905single line.
906
907dit(bf(--bwlimit=KBPS)) This option allows you to specify a maximum
908transfer rate in kilobytes per second. This option is most effective when
909using rsync with large files (several megabytes and up). Due to the nature
910of rsync transfers, blocks of data are sent, then if rsync determines the
911transfer was too fast, it will wait before sending the next data block. The
912result is an average transfer rate equaling the specified limit. A value
913of zero specifies no limit.
914
915dit(bf(--write-batch=FILE)) Record a file that can later be applied to
916another identical destination with --read-batch. See the "BATCH MODE"
917section for details.
918
919dit(bf(--read-batch=FILE)) Apply all of the changes stored in FILE, a
920file previously generated by --write-batch.
921If em(FILE) is "-" the batch data will be read from standard input.
922See the "BATCH MODE" section for details.
923
924dit(bf(-4, --ipv4) or bf(-6, --ipv6)) Tells rsync to prefer IPv4/IPv6
925when creating sockets. This only affects sockets that rsync has direct
926control over, such as the outgoing socket when directly contacting an
927rsync daemon, or the incoming sockets that an rsync daemon uses to
928listen for connections. One of these options may be required in older
929versions of Linux to work around an IPv6 bug in the kernel (if you see
930an "address already in use" error when nothing else is using the port,
931try specifying --ipv6 or --ipv4 when starting the daemon).
932
933dit(bf(--checksum-seed=NUM)) Set the MD4 checksum seed to the integer
934NUM. This 4 byte checksum seed is included in each block and file
935MD4 checksum calculation. By default the checksum seed is generated
936by the server and defaults to the current time(). This option
937is used to set a specific checksum seed, which is useful for
938applications that want repeatable block and file checksums, or
939in the case where the user wants a more random checksum seed.
940Note that setting NUM to 0 causes rsync to use the default of time()
941for checksum seed.
942
943enddit()
944
945manpagesection(EXCLUDE PATTERNS)
946
947The exclude and include patterns specified to rsync allow for flexible
948selection of which files to transfer and which files to skip.
949
950Rsync builds an ordered list of include/exclude options as specified on
951the command line. Rsync checks each file and directory
952name against each exclude/include pattern in turn. The first matching
953pattern is acted on. If it is an exclude pattern, then that file is
954skipped. If it is an include pattern then that filename is not
955skipped. If no matching include/exclude pattern is found then the
956filename is not skipped.
957
958The filenames matched against the exclude/include patterns are relative
959to the "root of the transfer". If you think of the transfer as a
960subtree of names that are being sent from sender to receiver, the root
961is where the tree starts to be duplicated in the destination directory.
962This root governs where patterns that start with a / match (see below).
963
964Because the matching is relative to the transfer-root, changing the
965trailing slash on a source path or changing your use of the --relative
966option affects the path you need to use in your matching (in addition to
967changing how much of the file tree is duplicated on the destination
968system). The following examples demonstrate this.
969
970Let's say that we want to match two source files, one with an absolute
971path of "/home/me/foo/bar", and one with a path of "/home/you/bar/baz".
972Here is how the various command choices differ for a 2-source transfer:
973
974verb(
975 Example cmd: rsync -a /home/me /home/you /dest
976 +/- pattern: /me/foo/bar
977 +/- pattern: /you/bar/baz
978 Target file: /dest/me/foo/bar
979 Target file: /dest/you/bar/baz
980
981 Example cmd: rsync -a /home/me/ /home/you/ /dest
982 +/- pattern: /foo/bar (note missing "me")
983 +/- pattern: /bar/baz (note missing "you")
984 Target file: /dest/foo/bar
985 Target file: /dest/bar/baz
986
987 Example cmd: rsync -a --relative /home/me/ /home/you /dest
988 +/- pattern: /home/me/foo/bar (note full path)
989 +/- pattern: /home/you/bar/baz (ditto)
990 Target file: /dest/home/me/foo/bar
991 Target file: /dest/home/you/bar/baz
992
993 Example cmd: cd /home; rsync -a --relative me/foo you/ /dest
994 +/- pattern: /me/foo/bar (starts at specified path)
995 +/- pattern: /you/bar/baz (ditto)
996 Target file: /dest/me/foo/bar
997 Target file: /dest/you/bar/baz
998)
999
1000The easiest way to see what name you should include/exclude is to just
1001look at the output when using --verbose and put a / in front of the name
1002(use the --dry-run option if you're not yet ready to copy any files).
1003
1004Note that, when using the --recursive (-r) option (which is implied by -a),
1005every subcomponent of
1006every path is visited from the top down, so include/exclude patterns get
1007applied recursively to each subcomponent.
1008The exclude patterns actually short-circuit the directory traversal stage
1009when rsync finds the files to send. If a pattern excludes a particular
1010parent directory, it can render a deeper include pattern ineffectual
1011because rsync did not descend through that excluded section of the
1012hierarchy.
1013
1014Note also that the --include and --exclude options take one pattern
1015each. To add multiple patterns use the --include-from and
1016--exclude-from options or multiple --include and --exclude options.
1017
1018The patterns can take several forms. The rules are:
1019
1020itemize(
1021
1022 it() if the pattern starts with a / then it is matched against the
1023 start of the filename, otherwise it is matched against the end of
1024 the filename.
1025 This is the equivalent of a leading ^ in regular expressions.
1026 Thus "/foo" would match a file called "foo" at the transfer-root
1027 (see above for how this is different from the filesystem-root).
1028 On the other hand, "foo" would match any file called "foo"
1029 anywhere in the tree because the algorithm is applied recursively from
1030 top down; it behaves as if each path component gets a turn at being the
1031 end of the file name.
1032
1033 it() if the pattern ends with a / then it will only match a
1034 directory, not a file, link, or device.
1035
1036 it() if the pattern contains a wildcard character from the set
1037 *?[ then expression matching is applied using the shell filename
1038 matching rules. Otherwise a simple string match is used.
1039
1040 it() the double asterisk pattern "**" will match slashes while a
1041 single asterisk pattern "*" will stop at slashes.
1042
1043 it() if the pattern contains a / (not counting a trailing /) or a "**"
1044 then it is matched against the full filename, including any leading
1045 directory. If the pattern doesn't contain a / or a "**", then it is
1046 matched only against the final component of the filename. Again,
1047 remember that the algorithm is applied recursively so "full filename" can
1048 actually be any portion of a path below the starting directory.
1049
1050 it() if the pattern starts with "+ " (a plus followed by a space)
1051 then it is always considered an include pattern, even if specified as
1052 part of an exclude option. The prefix is discarded before matching.
1053
1054 it() if the pattern starts with "- " (a minus followed by a space)
1055 then it is always considered an exclude pattern, even if specified as
1056 part of an include option. The prefix is discarded before matching.
1057
1058 it() if the pattern is a single exclamation mark ! then the current
1059 include/exclude list is reset, removing all previously defined patterns.
1060)
1061
1062The +/- rules are most useful in a list that was read from a file, allowing
1063you to have a single exclude list that contains both include and exclude
1064options in the proper order.
1065
1066Remember that the matching occurs at every step in the traversal of the
1067directory hierarchy, so you must be sure that all the parent directories of
1068the files you want to include are not excluded. This is particularly
1069important when using a trailing '*' rule. For instance, this won't work:
1070
1071verb(
1072 + /some/path/this-file-will-not-be-found
1073 + /file-is-included
1074 - *
1075)
1076
1077This fails because the parent directory "some" is excluded by the '*' rule,
1078so rsync never visits any of the files in the "some" or "some/path"
1079directories. One solution is to ask for all directories in the hierarchy
1080to be included by using a single rule: --include='*/' (put it somewhere
1081before the --exclude='*' rule). Another solution is to add specific
1082include rules for all the parent dirs that need to be visited. For
1083instance, this set of rules works fine:
1084
1085verb(
1086 + /some/
1087 + /some/path/
1088 + /some/path/this-file-is-found
1089 + /file-also-included
1090 - *
1091)
1092
1093Here are some examples of exclude/include matching:
1094
1095itemize(
1096 it() --exclude "*.o" would exclude all filenames matching *.o
1097 it() --exclude "/foo" would exclude a file called foo in the transfer-root directory
1098 it() --exclude "foo/" would exclude any directory called foo
1099 it() --exclude "/foo/*/bar" would exclude any file called bar two
1100 levels below a directory called foo in the transfer-root directory
1101 it() --exclude "/foo/**/bar" would exclude any file called bar two
1102 or more levels below a directory called foo in the transfer-root directory
1103 it() --include "*/" --include "*.c" --exclude "*" would include all
1104 directories and C source files
1105 it() --include "foo/" --include "foo/bar.c" --exclude "*" would include
1106 only foo/bar.c (the foo/ directory must be explicitly included or
1107 it would be excluded by the "*")
1108)
1109
1110manpagesection(BATCH MODE)
1111
1112bf(Note:) Batch mode should be considered experimental in this version
1113of rsync. The interface and behavior have now stabilized, though, so
1114feel free to try this out.
1115
1116Batch mode can be used to apply the same set of updates to many
1117identical systems. Suppose one has a tree which is replicated on a
1118number of hosts. Now suppose some changes have been made to this
1119source tree and those changes need to be propagated to the other
1120hosts. In order to do this using batch mode, rsync is run with the
1121write-batch option to apply the changes made to the source tree to one
1122of the destination trees. The write-batch option causes the rsync
1123client to store in a "batch file" all the information needed to repeat
1124this operation against other, identical destination trees.
1125
1126To apply the recorded changes to another destination tree, run rsync
1127with the read-batch option, specifying the name of the same batch
1128file, and the destination tree. Rsync updates the destination tree
1129using the information stored in the batch file.
1130
1131For convenience, one additional file is creating when the write-batch
1132option is used. This file's name is created by appending
1133".sh" to the batch filename. The .sh file contains
1134a command-line suitable for updating a destination tree using that
1135batch file. It can be executed using a Bourne(-like) shell, optionally
1136passing in an alternate destination tree pathname which is then used
1137instead of the original path. This is useful when the destination tree
1138path differs from the original destination tree path.
1139
1140Generating the batch file once saves having to perform the file
1141status, checksum, and data block generation more than once when
1142updating multiple destination trees. Multicast transport protocols can
1143be used to transfer the batch update files in parallel to many hosts
1144at once, instead of sending the same data to every host individually.
1145
1146Examples:
1147
1148verb(
1149 $ rsync --write-batch=foo -a host:/source/dir/ /adest/dir/
1150 $ scp foo* remote:
1151 $ ssh remote ./foo.sh /bdest/dir/
1152)
1153
1154verb(
1155 $ rsync --write-batch=foo -a /source/dir/ /adest/dir/
1156 $ ssh remote rsync --read-batch=- -a /bdest/dir/ <foo
1157)
1158
1159In these examples, rsync is used to update /adest/dir/ from /source/dir/
1160and the information to repeat this operation is stored in "foo" and
1161"foo.sh". The host "remote" is then updated with the batched data going
1162into the directory /bdest/dir. The differences between the two examples
1163reveals some of the flexibility you have in how you deal with batches:
1164
1165itemize(
1166
1167 it() The first example shows that the initial copy doesn't have to be
1168 local -- you can push or pull data to/from a remote host using either the
1169 remote-shell syntax or rsync daemon syntax, as desired.
1170
1171 it() The first example uses the created "foo.sh" file to get the right
1172 rsync options when running the read-batch command on the remote host.
1173
1174 it() The second example reads the batch data via standard input so that
1175 the batch file doesn't need to be copied to the remote machine first.
1176 This example avoids the foo.sh script because it needed to use a modified
1177 --read-batch option, but you could edit the script file if you wished to
1178 make use of it (just be sure that no other option is trying to use
1179 standard input, such as the "--exclude-from=-" option).
1180
1181)
1182
1183Caveats:
1184
1185The read-batch option expects the destination tree that it is updating
1186to be identical to the destination tree that was used to create the
1187batch update fileset. When a difference between the destination trees
1188is encountered the update might be discarded with no error (if the file
1189appears to be up-to-date already) or the file-update may be attempted
1190and then, if the file fails to verify, the update discarded with an
1191error. This means that it should be safe to re-run a read-batch operation
1192if the command got updated. If you wish to force the batched-update to
1193always be attempted regardless of the file's size and date, use the -I
1194option. If an error occurs, the destination tree will probably be in a
1195partially updated state. In that case, rsync can
1196be used in its regular (non-batch) mode of operation to fix up the
1197destination tree.
1198
1199The rsync version used on all destinations must be at least as new as the
1200one used to generate the batch file.
1201
1202The --dry-run (-n) option does not work in batch mode and yields a runtime
1203error.
1204
1205When reading a batch file, rsync will force the value of certain options
1206to match the data in the batch file if you didn't set them to the same
1207as the batch-writing command. Other options can (and should) be changed.
1208For instance
1209--write-batch changes to --read-batch, --files-from is dropped, and the
1210--include/--exclude options are not needed unless --delete is specified
1211without --delete-excluded.
1212
1213The code that creates the BATCH.sh file transforms any include/exclude
1214options into a single list that is appended as a "here" document to the
1215shell script file. An advanced user can use this to modify the exclude
1216list if a change in what gets deleted by --delete is desired. A normal
1217user can ignore this detail and just use the shell script as an easy way
1218to run the appropriate --read-batch command for the batched data.
1219
1220See bf(http://www.ils.unc.edu/i2dsi/unc_rsync+.html) for papers and technical
1221reports.
1222
1223manpagesection(SYMBOLIC LINKS)
1224
1225Three basic behaviors are possible when rsync encounters a symbolic
1226link in the source directory.
1227
1228By default, symbolic links are not transferred at all. A message
1229"skipping non-regular" file is emitted for any symlinks that exist.
1230
1231If bf(--links) is specified, then symlinks are recreated with the same
1232target on the destination. Note that bf(--archive) implies
1233bf(--links).
1234
1235If bf(--copy-links) is specified, then symlinks are "collapsed" by
1236copying their referent, rather than the symlink.
1237
1238rsync also distinguishes "safe" and "unsafe" symbolic links. An
1239example where this might be used is a web site mirror that wishes
1240ensure the rsync module they copy does not include symbolic links to
1241bf(/etc/passwd) in the public section of the site. Using
1242bf(--copy-unsafe-links) will cause any links to be copied as the file
1243they point to on the destination. Using bf(--safe-links) will cause
1244unsafe links to be omitted altogether.
1245
1246Symbolic links are considered unsafe if they are absolute symlinks
1247(start with bf(/)), empty, or if they contain enough bf("..")
1248components to ascend from the directory being copied.
1249
1250manpagesection(DIAGNOSTICS)
1251
1252rsync occasionally produces error messages that may seem a little
1253cryptic. The one that seems to cause the most confusion is "protocol
1254version mismatch - is your shell clean?".
1255
1256This message is usually caused by your startup scripts or remote shell
1257facility producing unwanted garbage on the stream that rsync is using
1258for its transport. The way to diagnose this problem is to run your
1259remote shell like this:
1260
1261verb(
1262 ssh remotehost /bin/true > out.dat
1263)
1264
1265then look at out.dat. If everything is working correctly then out.dat
1266should be a zero length file. If you are getting the above error from
1267rsync then you will probably find that out.dat contains some text or
1268data. Look at the contents and try to work out what is producing
1269it. The most common cause is incorrectly configured shell startup
1270scripts (such as .cshrc or .profile) that contain output statements
1271for non-interactive logins.
1272
1273If you are having trouble debugging include and exclude patterns, then
1274try specifying the -vv option. At this level of verbosity rsync will
1275show why each individual file is included or excluded.
1276
1277manpagesection(EXIT VALUES)
1278
1279startdit()
1280dit(bf(0)) Success
1281dit(bf(1)) Syntax or usage error
1282dit(bf(2)) Protocol incompatibility
1283dit(bf(3)) Errors selecting input/output files, dirs
1284dit(bf(4)) Requested action not supported: an attempt
1285was made to manipulate 64-bit files on a platform that cannot support
1286them; or an option was specified that is supported by the client and
1287not by the server.
1288dit(bf(5)) Error starting client-server protocol
1289dit(bf(10)) Error in socket I/O
1290dit(bf(11)) Error in file I/O
1291dit(bf(12)) Error in rsync protocol data stream
1292dit(bf(13)) Errors with program diagnostics
1293dit(bf(14)) Error in IPC code
1294dit(bf(20)) Received SIGUSR1 or SIGINT
1295dit(bf(21)) Some error returned by waitpid()
1296dit(bf(22)) Error allocating core memory buffers
1297dit(bf(23)) Partial transfer due to error
1298dit(bf(24)) Partial transfer due to vanished source files
1299dit(bf(30)) Timeout in data send/receive
1300enddit()
1301
1302manpagesection(ENVIRONMENT VARIABLES)
1303
1304startdit()
1305
1306dit(bf(CVSIGNORE)) The CVSIGNORE environment variable supplements any
1307ignore patterns in .cvsignore files. See the --cvs-exclude option for
1308more details.
1309
1310dit(bf(RSYNC_RSH)) The RSYNC_RSH environment variable allows you to
1311override the default shell used as the transport for rsync. Command line
1312options are permitted after the command name, just as in the -e option.
1313
1314dit(bf(RSYNC_PROXY)) The RSYNC_PROXY environment variable allows you to
1315redirect your rsync client to use a web proxy when connecting to a
1316rsync daemon. You should set RSYNC_PROXY to a hostname:port pair.
1317
1318dit(bf(RSYNC_PASSWORD)) Setting RSYNC_PASSWORD to the required
1319password allows you to run authenticated rsync connections to an rsync
1320daemon without user intervention. Note that this does not supply a
1321password to a shell transport such as ssh.
1322
1323dit(bf(USER) or bf(LOGNAME)) The USER or LOGNAME environment variables
1324are used to determine the default username sent to an rsync server.
1325If neither is set, the username defaults to "nobody".
1326
1327dit(bf(HOME)) The HOME environment variable is used to find the user's
1328default .cvsignore file.
1329
1330enddit()
1331
1332manpagefiles()
1333
1334/etc/rsyncd.conf or rsyncd.conf
1335
1336manpageseealso()
1337
1338rsyncd.conf(5)
1339
1340manpagediagnostics()
1341
1342manpagebugs()
1343
1344times are transferred as unix time_t values
1345
1346When transferring to FAT filesystems rsync may re-sync
1347unmodified files.
1348See the comments on the --modify-window option.
1349
1350file permissions, devices, etc. are transferred as native numerical
1351values
1352
1353see also the comments on the --delete option
1354
1355Please report bugs! See the website at
1356url(http://rsync.samba.org/)(http://rsync.samba.org/)
1357
1358manpagesection(CREDITS)
1359
1360rsync is distributed under the GNU public license. See the file
1361COPYING for details.
1362
1363A WEB site is available at
1364url(http://rsync.samba.org/)(http://rsync.samba.org/). The site
1365includes an FAQ-O-Matic which may cover questions unanswered by this
1366manual page.
1367
1368The primary ftp site for rsync is
1369url(ftp://rsync.samba.org/pub/rsync)(ftp://rsync.samba.org/pub/rsync).
1370
1371We would be delighted to hear from you if you like this program.
1372
1373This program uses the excellent zlib compression library written by
1374Jean-loup Gailly and Mark Adler.
1375
1376manpagesection(THANKS)
1377
1378Thanks to Richard Brent, Brendan Mackay, Bill Waite, Stephen Rothwell
1379and David Bell for helpful suggestions, patches and testing of rsync.
1380I've probably missed some people, my apologies if I have.
1381
1382Especial thanks also to: David Dykstra, Jos Backus, Sebastian Krahmer,
1383Martin Pool, Wayne Davison, J.W. Schultz.
1384
1385manpageauthor()
1386
1387rsync was originally written by Andrew Tridgell and Paul Mackerras.
1388Many people have later contributed to it.
1389
1390Mailing lists for support and development are available at
1391url(http://lists.samba.org)(lists.samba.org)