Provided by: cvs_1.12.13+real-15ubuntu0.1_amd64 
NAME
cvs - Concurrent Versions System
SYNOPSIS
cvs [ cvs_options ]
cvs_command [ command_options ] [ command_args ]
NOTE
This manpage is a summary of some of the features of cvs. It is auto-generated from an appendix of the
CVS manual. For more in-depth documentation, please consult the Cederqvist manual (via the cvs(GNU) link
in the MirBSD online (HTML) manual pages, the info CVS command or otherwise, as described in the SEE ALSO
section of this manpage). Cross-references in this man page refer to nodes in the same.
CVS commands
Guide to CVS commands
This appendix describes the overall structure of cvs commands, and describes some commands in detail
(others are described elsewhere; for a quick reference to cvs commands, see node 'Invoking CVS' in the
CVS manual).
Structure
Overall structure of CVS commands
The overall format of all cvs commands is:
cvs [ cvs_options ] cvs_command [ command_options ] [ command_args ]
cvs
The name of the cvs program.
cvs_options
Some options that affect all sub-commands of cvs. These are described below.
cvs_command
One of several different sub-commands. Some of the commands have aliases that can be used instead;
those aliases are noted in the reference manual for that command. There are only two situations where
you may omit cvs_command: cvs -H elicits a list of available commands, and cvs -v displays version
information on cvs itself.
command_options
Options that are specific for the command.
command_args
Arguments to the commands.
There is unfortunately some confusion between cvs_options and command_options. When given as a
cvs_option, some options only affect some of the commands. When given as a command_option it may have
a different meaning, and be accepted by more commands. In other words, do not take the above
categorization too seriously. Look at the documentation instead.
Exit status
CVS's exit status
cvs can indicate to the calling environment whether it succeeded or failed by setting its exit status.
The exact way of testing the exit status will vary from one operating system to another. For example in
a unix shell script the $? variable will be 0 if the last command returned a successful exit status, or
greater than 0 if the exit status indicated failure.
If cvs is successful, it returns a successful status; if there is an error, it prints an error message
and returns a failure status. The one exception to this is the cvs diff command. It will return a
successful status if it found no differences, or a failure status if there were differences or if there
was an error. Because this behavior provides no good way to detect errors, in the future it is possible
that cvs diff will be changed to behave like the other cvs commands.
~/.cvsrc
Default options and the ~/.cvsrc file There are some command_options that are used so often that you might have set up an alias or some other means to make sure you always specify that option. One example (the one that drove the implementation of the .cvsrc support, actually) is that many people find the default output of the diff command to be very hard to read, and that either context diffs or unidiffs are much easier to understand. The ~/.cvsrc file is a way that you can add default options to cvs_commands within cvs, instead of relying on aliases or other shell scripts. The format of the ~/.cvsrc file is simple. The file is searched for a line that begins with the same name as the cvs_command being executed. If a match is found, then the remainder of the line is split up (at whitespace characters) into separate options and added to the command arguments before any options from the command line. If a command has two names (e.g., checkout and co), the official name, not necessarily the one used on the command line, will be used to match against the file. So if this is the contents of the user's ~/.cvsrc file: log -N diff -uN rdiff -u update -Pd checkout -P release -d the command cvs checkout foo would have the -P option added to the arguments, as well as cvs co foo. With the example file above, the output from cvs diff foobar will be in unidiff format. cvs diff -c foobar will provide context diffs, as usual. Getting "old" format diffs would be slightly more complicated, because diff doesn't have an option to specify use of the "old" format, so you would need cvs -f diff foobar. In place of the command name you can use cvs to specify global options (see node 'Global options' in the CVS manual). For example the following line in .cvsrc cvs -z6 causes cvs to use compression level 6.
Global options
The available cvs_options (that are given to the left of cvs_command) are:
--allow-root=rootdir
May be invoked multiple times to specify one legal cvsroot directory with each invocation. Also causes
CVS to preparse the configuration file for each specified root, which can be useful when configuring
write proxies, See node 'Password authentication server' in the CVS manual & node 'Write proxies' in
the CVS manual.
-a
Authenticate all communication between the client and the server. Only has an effect on the cvs
client. As of this writing, this is only implemented when using a GSSAPI connection (see node 'GSSAPI
authenticated' in the CVS manual). Authentication prevents certain sorts of attacks involving
hijacking the active tcp connection. Enabling authentication does not enable encryption.
-b bindir
In cvs 1.9.18 and older, this specified that rcs programs are in the bindir directory. Current
versions of cvs do not run rcs programs; for compatibility this option is accepted, but it does
nothing.
-T tempdir
Use tempdir as the directory where temporary files are located.
The cvs client and server store temporary files in a temporary directory. The path to this temporary
directory is set via, in order of precedence:
• The argument to the global -T option.
• The value set for TmpDir in the config file (server only - see node 'config' in the CVS manual).
• The contents of the $TMPDIR environment variable (%TMPDIR% on Windows - see node 'Environment
variables' in the CVS manual).
• /tmp
Temporary directories should always be specified as an absolute pathname. When running a CVS client,
-T affects only the local process; specifying -T for the client has no effect on the server and vice
versa.
-d cvs_root_directory
Use cvs_root_directory as the root directory pathname of the repository. Overrides the setting of the
$CVSROOT environment variable. See node 'Repository' in the CVS manual.
-e editor
Use editor to enter revision log information. Overrides the setting of the $CVSEDITOR and $EDITOR
environment variables. For more information, see node 'Committing your changes' in the CVS manual.
-f
Do not read the ~/.cvsrc file. This option is most often used because of the non-orthogonality of the
cvs option set. For example, the cvs log option -N (turn off display of tag names) does not have a
corresponding option to turn the display on. So if you have -N in the ~/.cvsrc entry for log, you may
need to use -f to show the tag names.
-g
Forges group-writable permissions on files in the working copy. This option is typically used when you
have multiple users sharing a single checked out source tree, allowing them to operate their shells
with a less dangerous umask at the expense of cvs security. To use this feature, create a directory to
hold the checked-out source tree, set it to a private group, and set up the directory such that files
created under it inherit the gid of the directory. On BSD systems, this occurs automatically. On SYSV
systems and GNU/Linux, the sgid bit must be set on the directory for this. The users who are to share
the checked out tree must be placed in that group which owns the directory.
Note that the sharing of a single checked-out source tree is very different from giving several users
access to a common cvs repository. Access to a common cvs repository already maintains shared
group-write permissions and does not require this option.
Due to the security implications, setting this option globally in your .cvsrc file is strongly
discouraged; if you must, ensure all source checkouts are "firewalled" within a private group or a
private mode 0700 directory.
This option is a MidnightBSD extension merged into MirBSD cvs.
-H
--help
Display usage information about the specified cvs_command (but do not actually execute the command).
If you don't specify a command name, cvs -H displays overall help for cvs, including a list of other
help options.
-R
Turns on read-only repository mode. This allows one to check out from a read-only repository, such as
within an anoncvs server, or from a cd-rom repository.
Same effect as if the CVSREADONLYFS environment variable is set. Using -R can also considerably speed
up checkouts over NFS.
-n
Do not change any files. Attempt to execute the cvs_command, but only to issue reports; do not remove,
update, or merge any existing files, or create any new files.
Note that cvs will not necessarily produce exactly the same output as without -n. In some cases the
output will be the same, but in other cases cvs will skip some of the processing that would have been
required to produce the exact same output.
-Q
Cause the command to be really quiet; the command will only generate output for serious problems.
-q
Cause the command to be somewhat quiet; informational messages, such as reports of recursion through
subdirectories, are suppressed.
-r
Make new working files read-only. Same effect as if the $CVSREAD environment variable is set (see node
'Environment variables' in the CVS manual). The default is to make working files writable, unless
watches are on (see node 'Watches' in the CVS manual).
-s variable=value
Set a user variable (see node 'Variables' in the CVS manual).
-t
Trace program execution; display messages showing the steps of cvs activity. Particularly useful with
-n to explore the potential impact of an unfamiliar command.
-v
--version
Display version and copyright information for cvs.
-w
Make new working files read-write. Overrides the setting of the $CVSREAD environment variable. Files
are created read-write by default, unless $CVSREAD is set or -r is given.
-x
Encrypt all communication between the client and the server. Only has an effect on the cvs client. As
of this writing, this is only implemented when using a GSSAPI connection (see node 'GSSAPI
authenticated' in the CVS manual) or a Kerberos connection (see node 'Kerberos authenticated' in the
CVS manual). Enabling encryption implies that message traffic is also authenticated. Encryption
support is not available by default; it must be enabled using a special configure option,
--enable-encryption, when you build cvs.
-z level
Request compression level for network traffic. cvs interprets level identically to the gzip program.
Valid levels are 1 (high speed, low compression) to 9 (low speed, high compression), or 0 to disable
compression (the default). Data sent to the server will be compressed at the requested level and the
client will request the server use the same compression level for data returned. The server will use
the closest level allowed by the server administrator to compress returned data. This option only has
an effect when passed to the cvs client.
Common options
Common command options
This section describes the command_options that are available across several cvs commands. These options
are always given to the right of cvs_command. Not all commands support all of these options; each option
is only supported for commands where it makes sense. However, when a command has one of these options
you can almost always count on the same behavior of the option as in other commands. (Other command
options, which are listed with the individual commands, may have different behavior from one cvs command
to the other).
Note: the history command is an exception; it supports many options that conflict even with these
standard options.
-D date_spec
Use the most recent revision no later than date_spec. date_spec is a single argument, a date
description specifying a date in the past.
The specification is sticky when you use it to make a private copy of a source file; that is, when you
get a working file using -D, cvs records the date you specified, so that further updates in the same
directory will use the same date (for more information on sticky tags/dates, see node 'Sticky tags' in
the CVS manual).
-D is available with the annotate, checkout, diff, export, history, ls, rdiff, rls, rtag, tag, and
update commands. (The history command uses this option in a slightly different way; see node 'history
options' in the CVS manual).
For a complete description of the date formats accepted by cvs, see node 'Date input formats' in the
CVS manual.
Remember to quote the argument to the -D flag so that your shell doesn't interpret spaces as argument
separators. A command using the -D flag can look like this:
$ cvs diff -D "1 hour ago" cvs.texinfo
-f
When you specify a particular date or tag to cvs commands, they normally ignore files that do not
contain the tag (or did not exist prior to the date) that you specified. Use the -f option if you want
files retrieved even when there is no match for the tag or date. (The most recent revision of the file
will be used).
Note that even with -f, a tag that you specify must exist (that is, in some file, not necessary in
every file). This is so that cvs will continue to give an error if you mistype a tag name.
-f is available with these commands: annotate, checkout, export, rdiff, rtag, and update.
WARNING: The commit and remove commands also have a -f option, but it has a different behavior for
those commands. See node 'commit options' in the CVS manual, and node 'Removing files' in the CVS
manual.
-k kflag
Override the default processing of RCS keywords other than -kb. See node 'Keyword substitution' in the
CVS manual, for the meaning of kflag. Used with the checkout and update commands, your kflag
specification is sticky; that is, when you use this option with a checkout or update command, cvs
associates your selected kflag with any files it operates on, and continues to use that kflag with
future commands on the same files until you specify otherwise.
The -k option is available with the add, checkout, diff, export, import, rdiff, and update commands.
WARNING: Prior to CVS version 1.12.2, the -k flag overrode the -kb indication for a binary file. This
could sometimes corrupt binary files. See node 'Merging and keywords' in the CVS manual, for more.
-l
Local; run only in current working directory, rather than recursing through subdirectories.
Available with the following commands: annotate, checkout, commit, diff, edit, editors, export, log,
rdiff, remove, rtag, status, tag, unedit, update, watch, and watchers.
-m message
Use message as log information, instead of invoking an editor.
Available with the following commands: add, commit and import.
-n
Do not run any tag program. (A program can be specified to run in the modules database (see node
'modules' in the CVS manual); this option bypasses it).
Note: this is not the same as the cvs -n program option, which you can specify to the left of a cvs
command!
Available with the checkout, commit, export, and rtag commands.
-P
Prune empty directories. See node 'Removing directories' in the CVS manual.
-p
Pipe the files retrieved from the repository to standard output, rather than writing them in the
current directory. Available with the checkout and update commands.
-R
Process directories recursively. This is the default for all cvs commands, with the exception of ls &
rls.
Available with the following commands: annotate, checkout, commit, diff, edit, editors, export, ls,
rdiff, remove, rls, rtag, status, tag, unedit, update, watch, and watchers.
-r tag
-r tag[:date]
Use the revision specified by the tag argument (and the date argument for the commands which accept it)
instead of the default head revision. As well as arbitrary tags defined with the tag or rtag command,
two special tags are always available: HEAD refers to the most recent version available in the
repository (also known as the tip of the MAIN branch, also known as trunk; the name of a branch refers
to its tip; this version of cvs introduces .bhead, but only for the diff command, for the same), and
BASE refers to the revision you last checked out into the current working directory.
The tag specification is sticky when you use this with checkout or update to make your own copy of a
file: cvs remembers the tag and continues to use it on future update commands, until you specify
otherwise (for more information on sticky tags/dates, see node 'Sticky tags' in the CVS manual).
The tag can be either a symbolic or numeric tag, as described in node 'Tags' in the CVS manual, or the
name of a branch, as described in node 'Branching and merging' in the CVS manual. When tag is the name
of a branch, some commands accept the optional date argument to specify the revision as of the given
date on the branch. When a command expects a specific revision, the name of a branch is interpreted as
the most recent revision on that branch.
As a MirOS cvs extension, specifying BASE as the date portion of the argument yields the base revision
of the branch specified by the tag portion of the argument, i.e. the revision on the parent branch the
tag branch split off, or, where both branches were the same. This option has not received very much
testing, beware!
Specifying the -q global option along with the -r command option is often useful, to suppress the
warning messages when the rcs file does not contain the specified tag.
Note: this is not the same as the overall cvs -r option, which you can specify to the left of a cvs
command!
-r tag is available with the commit and history commands.
-r tag[:date] is available with the annotate, checkout, diff, export, rdiff, rtag, and update commands.
-W
Specify file names that should be filtered. You can use this option repeatedly. The spec can be a
file name pattern of the same type that you can specify in the .cvswrappers file. Available with the
following commands: import, and update.
admin
Administration
• Requires: repository, working directory.
• Changes: repository.
• Synonym: rcs
This is the cvs interface to assorted administrative facilities. Some of them have questionable
usefulness for cvs but exist for historical purposes. Some of the questionable options are likely to
disappear in the future. This command does work recursively, so extreme care should be used.
On unix, if there is a group named cvsadmin, only members of that group can run cvs admin commands,
except for those specified using the UserAdminOptions configuration option in the CVSROOT/config file.
Options specified using UserAdminOptions can be run by any user. See node 'config' in the CVS manual
for more on UserAdminOptions.
The cvsadmin group should exist on the server, or any system running the non-client/server cvs. To
disallow cvs admin for all users, create a group with no users in it. On NT, the cvsadmin feature does
not exist and all users can run cvs admin.
admin options
Some of these options have questionable usefulness for cvs but exist for historical purposes. Some even
make it impossible to use cvs until you undo the effect!
-Aoldfile
Might not work together with cvs. Append the access list of oldfile to the access list of the rcs
file.
-alogins
Might not work together with cvs. Append the login names appearing in the comma-separated list logins
to the access list of the rcs file.
-b[rev]
Set the default branch to rev. In cvs, you normally do not manipulate default branches; sticky tags
(see node 'Sticky tags' in the CVS manual) are a better way to decide which branch you want to work on.
There is one reason to run cvs admin -b: to revert to the vendor's version when using vendor branches
(see node 'Reverting local changes' in the CVS manual). There can be no space between -b and its
argument.
-cstring
Sets the comment leader to string. The comment leader is not used by current versions of cvs or rcs
5.7. Therefore, you can almost surely not worry about it. See node 'Keyword substitution' in the CVS
manual.
-e[logins]
Might not work together with cvs. Erase the login names appearing in the comma-separated list logins
from the access list of the RCS file. If logins is omitted, erase the entire access list. There can
be no space between -e and its argument.
-I
Run interactively, even if the standard input is not a terminal. This option does not work with the
client/server cvs and is likely to disappear in a future release of cvs.
-i
Useless with cvs. This creates and initializes a new rcs file, without depositing a revision. With
cvs, add files with the cvs add command (see node 'Adding files' in the CVS manual).
-ksubst
Set the default keyword substitution to subst. See node 'Keyword substitution' in the CVS manual.
Giving an explicit -k option to cvs update, cvs export, or cvs checkout overrides this default.
-l[rev]
Lock the revision with number rev. If a branch is given, lock the latest revision on that branch. If
rev is omitted, lock the latest revision on the default branch. There can be no space between -l and
its argument.
This can be used in conjunction with the rcslock.pl script in the contrib directory of the cvs source
distribution to provide reserved checkouts (where only one user can be editing a given file at a time).
See the comments in that file for details (and see the README file in that directory for disclaimers
about the unsupported nature of contrib). According to comments in that file, locking must set to
strict (which is the default).
-L
Set locking to strict. Strict locking means that the owner of an RCS file is not exempt from locking
for checkin. For use with cvs, strict locking must be set; see the discussion under the -l option
above.
-mrev:msg
Replace the log message of revision rev with msg.
-Nname[:[rev]]
Act like -n, except override any previous assignment of name. For use with magic branches, see node
'Magic branch numbers' in the CVS manual.
-nname[:[rev]]
Associate the symbolic name name with the branch or revision rev. It is normally better to use cvs tag
or cvs rtag instead. Delete the symbolic name if both : and rev are omitted; otherwise, print an error
message if name is already associated with another number. If rev is symbolic, it is expanded before
association. A rev consisting of a branch number followed by a . stands for the current latest
revision in the branch. A : with an empty rev stands for the current latest revision on the default
branch, normally the trunk. For example, cvs admin -nname: associates name with the current latest
revision of all the RCS files; this contrasts with cvs admin -nname:$ which associates name with the
revision numbers extracted from keyword strings in the corresponding working files.
-orange
Deletes (outdates) the revisions given by range.
Note that this command can be quite dangerous unless you know exactly what you are doing (for example
see the warnings below about how the rev1:rev2 syntax is confusing).
If you are short on disc this option might help you. But think twice before using it—there is no way
short of restoring the latest backup to undo this command! If you delete different revisions than you
planned, either due to carelessness or (heaven forbid) a cvs bug, there is no opportunity to correct
the error before the revisions are deleted. It probably would be a good idea to experiment on a copy
of the repository first.
Specify range in one of the following ways:
rev1::rev2
Collapse all revisions between rev1 and rev2, so that cvs only stores the differences associated with
going from rev1 to rev2, not intermediate steps. For example, after -o 1.3::1.5 one can retrieve
revision 1.3, revision 1.5, or the differences to get from 1.3 to 1.5, but not the revision 1.4, or
the differences between 1.3 and 1.4. Other examples: -o 1.3::1.4 and -o 1.3::1.3 have no effect,
because there are no intermediate revisions to remove.
::rev
Collapse revisions between the beginning of the branch containing rev and rev itself. The
branchpoint and rev are left intact. For example, -o ::1.3.2.6 deletes revision 1.3.2.1, revision
1.3.2.5, and everything in between, but leaves 1.3 and 1.3.2.6 intact.
rev::
Collapse revisions between rev and the end of the branch containing rev. Revision rev is left intact
but the head revision is deleted.
rev
Delete the revision rev. For example, -o 1.3 is equivalent to -o 1.2::1.4.
rev1:rev2
Delete the revisions from rev1 to rev2, inclusive, on the same branch. One will not be able to
retrieve rev1 or rev2 or any of the revisions in between. For example, the command cvs admin
-oR_1_01:R_1_02 . is rarely useful. It means to delete revisions up to, and including, the tag
R_1_02. But beware! If there are files that have not changed between R_1_02 and R_1_03 the file
will have the same numerical revision number assigned to the tags R_1_02 and R_1_03. So not only
will it be impossible to retrieve R_1_02; R_1_03 will also have to be restored from the tapes! In
most cases you want to specify rev1::rev2 instead.
:rev
Delete revisions from the beginning of the branch containing rev up to and including rev.
rev:
Delete revisions from revision rev, including rev itself, to the end of the branch containing rev.
None of the revisions to be deleted may have branches or locks.
If any of the revisions to be deleted have symbolic names, and one specifies one of the :: syntaxes,
then cvs will give an error and not delete any revisions. If you really want to delete both the
symbolic names and the revisions, first delete the symbolic names with cvs tag -d, then run cvs admin
-o. If one specifies the non-:: syntaxes, then cvs will delete the revisions but leave the symbolic
names pointing to nonexistent revisions. This behavior is preserved for compatibility with previous
versions of cvs, but because it isn't very useful, in the future it may change to be like the ::
case.
Due to the way cvs handles branches rev cannot be specified symbolically if it is a branch. See node
'Magic branch numbers' in the CVS manual, for an explanation.
Make sure that no-one has checked out a copy of the revision you outdate. Strange things will happen
if he starts to edit it and tries to check it back in. For this reason, this option is not a good
way to take back a bogus commit; commit a new revision undoing the bogus change instead (see node
'Merging two revisions' in the CVS manual).
-q
Run quietly; do not print diagnostics.
-sstate[:rev]
Useful with cvs. Set the state attribute of the revision rev to state. If rev is a branch number,
assume the latest revision on that branch. If rev is omitted, assume the latest revision on the
default branch. Any identifier is acceptable for state. A useful set of states is Exp (for
experimental), Stab (for stable), and Rel (for released). By default, the state of a new revision is
set to Exp when it is created. The state is visible in the output from cvs log (see node 'log' in the
CVS manual), and in the $Log$ and $State$ keywords (see node 'Keyword substitution' in the CVS manual).
Note that cvs uses the dead state for its own purposes (see node 'Attic' in the CVS manual); to take a
file to or from the dead state use commands like cvs remove and cvs add (see node 'Adding and removing'
in the CVS manual), not cvs admin -s.
-t[file]
Useful with cvs. Write descriptive text from the contents of the named file into the RCS file,
deleting the existing text. The file pathname may not begin with -. The descriptive text can be seen
in the output from cvs log (see node 'log' in the CVS manual). There can be no space between -t and
its argument.
If file is omitted, obtain the text from standard input, terminated by end-of-file or by a line
containing . by itself. Prompt for the text if interaction is possible; see -I.
-t-string
Similar to -tfile. Write descriptive text from the string into the rcs file, deleting the existing
text. There can be no space between -t and its argument.
-U
Set locking to non-strict. Non-strict locking means that the owner of a file need not lock a revision
for checkin. For use with cvs, strict locking must be set; see the discussion under the -l option
above.
-u[rev]
See the option -l above, for a discussion of using this option with cvs. Unlock the revision with
number rev. If a branch is given, unlock the latest revision on that branch. If rev is omitted,
remove the latest lock held by the caller. Normally, only the locker of a revision may unlock it;
somebody else unlocking a revision breaks the lock. This causes the original locker to be sent a
commit notification (see node 'Getting Notified' in the CVS manual). There can be no space between -u
and its argument.
-Vn
In previous versions of cvs, this option meant to write an rcs file which would be acceptable to rcs
version n, but it is now obsolete and specifying it will produce an error.
-xsuffixes
In previous versions of cvs, this was documented as a way of specifying the names of the rcs files.
However, cvs has always required that the rcs files used by cvs end in ,v, so this option has never
done anything useful.
annotate
What revision modified each line of a file?
• Synopsis: annotate [options] files...
• Requires: repository.
• Changes: nothing.
For each file in files, print the head revision of the trunk, together with information on the last
modification for each line. If backwards annotation is requested, show the first modification after
the specified revision. (Backwards annotation currently appears to be broken.)
annotate options
These standard options are supported by annotate (see node 'Common options' in the CVS manual, for a
complete description of them):
-b
Backwards, show when a line was removed. Currently appears to be broken.
-l
Local directory only, no recursion.
-R
Process directories recursively.
-f
Use head revision if tag/date not found.
-F
Annotate binary files.
-r tag[:date]
Annotate file as of specified revision/tag or, when date is specified and tag is a branch tag, the
version from the branch tag as it existed on date. See node 'Common options' in the CVS manual.
-D date
Annotate file as of specified date.
annotate example
For example:
$ cvs annotate ssfile
Annotations for ssfile
***************
1.1 (mary 27-Mar-96): ssfile line 1
1.2 (joe 28-Mar-96): ssfile line 2
The file ssfile currently contains two lines. The ssfile line 1 line was checked in by mary on March 27.
Then, on March 28, joe added a line ssfile line 2, without modifying the ssfile line 1 line. This report
doesn't tell you anything about lines which have been deleted or replaced; you need to use cvs diff for
that (see node 'diff' in the CVS manual).
The options to cvs annotate are listed in node 'Invoking CVS' in the CVS manual, and can be used to
select the files and revisions to annotate. The options are described in more detail there and in node
'Common options' in the CVS manual.
checkout
Check out sources for editing
• Synopsis: checkout [options] modules...
• Requires: repository.
• Changes: working directory.
• Synonyms: co, get
Create or update a working directory containing copies of the source files specified by modules. You
must execute checkout before using most of the other cvs commands, since most of them operate on your
working directory.
The modules are either symbolic names for some collection of source directories and files, or paths to
directories or files in the repository. The symbolic names are defined in the modules file. See node
'modules' in the CVS manual.
Depending on the modules you specify, checkout may recursively create directories and populate them
with the appropriate source files. You can then edit these source files at any time (regardless of
whether other software developers are editing their own copies of the sources); update them to include
new changes applied by others to the source repository; or commit your work as a permanent change to
the source repository.
Note that checkout is used to create directories. The top-level directory created is always added to
the directory where checkout is invoked, and usually has the same name as the specified module. In the
case of a module alias, the created sub-directory may have a different name, but you can be sure that
it will be a sub-directory, and that checkout will show the relative path leading to each file as it is
extracted into your private work area (unless you specify the -Q global option).
The files created by checkout are created read-write, unless the -r option to cvs (see node 'Global
options' in the CVS manual) is specified, the CVSREAD environment variable is specified (see node
'Environment variables' in the CVS manual), or a watch is in effect for that file (see node 'Watches'
in the CVS manual).
Note that running checkout on a directory that was already built by a prior checkout is also permitted.
This is similar to specifying the -d option to the update command in the sense that new directories
that have been created in the repository will appear in your work area. However, checkout takes a
module name whereas update takes a directory name. Also to use checkout this way it must be run from
the top level directory (where you originally ran checkout from), so before you run checkout to update
an existing directory, don't forget to change your directory to the top level directory.
For the output produced by the checkout command see node 'update output' in the CVS manual.
checkout options
These standard options are supported by checkout (see node 'Common options' in the CVS manual, for a
complete description of them):
-D date
Use the most recent revision no later than date. This option is sticky, and implies -P. See node
'Sticky tags' in the CVS manual, for more information on sticky tags/dates.
-f
Only useful with the -D or -r flags. If no matching revision is found, retrieve the most recent
revision (instead of ignoring the file).
-k kflag
Process keywords according to kflag. See node 'Keyword substitution' in the CVS manual. This option
is sticky; future updates of this file in this working directory will use the same kflag. The status
command can be viewed to see the sticky options. See node 'Invoking CVS' in the CVS manual, for more
information on the status command.
-l
Local; run only in current working directory.
-n
Do not run any checkout program (as specified with the -o option in the modules file; see node
'modules' in the CVS manual).
-P
Prune empty directories. See node 'Moving directories' in the CVS manual.
-p
Pipe files to the standard output.
-R
Checkout directories recursively. This option is on by default.
-r tag[:date]
Checkout the revision specified by tag or, when date is specified and tag is a branch tag, the version
from the branch tag as it existed on date. This option is sticky, and implies -P. See node 'Sticky
tags' in the CVS manual, for more information on sticky tags/dates. Also, see node 'Common options' in
the CVS manual.
In addition to those, you can use these special command options with checkout:
-A
Reset any sticky tags, dates, or -k options. See node 'Sticky tags' in the CVS manual, for more
information on sticky tags/dates.
-c
Copy the module file, sorted, to the standard output, instead of creating or modifying any files or
directories in your working directory.
-d dir
Create a directory called dir for the working files, instead of using the module name. In general,
using this flag is equivalent to using mkdir dir; cd dir followed by the checkout command without the
-d flag.
There is an important exception, however. It is very convenient when checking out a single item to
have the output appear in a directory that doesn't contain empty intermediate directories. In this
case only, cvs tries to ``shorten'' pathnames to avoid those empty directories.
For example, given a module foo that contains the file bar.c, the command cvs co -d dir foo will create
directory dir and place bar.c inside. Similarly, given a module bar which has subdirectory baz wherein
there is a file quux.c, the command cvs co -d dir bar/baz will create directory dir and place quux.c
inside.
Using the -N flag will defeat this behavior. Given the same module definitions above, cvs co -N -d dir
foo will create directories dir/foo and place bar.c inside, while cvs co -N -d dir bar/baz will create
directories dir/bar/baz and place quux.c inside.
-j tag
With two -j options, merge changes from the revision specified with the first -j option to the revision
specified with the second j option, into the working directory.
With one -j option, merge changes from the ancestor revision to the revision specified with the -j
option, into the working directory. The ancestor revision is the common ancestor of the revision which
the working directory is based on, and the revision specified in the -j option.
In addition, each -j option can contain an optional date specification which, when used with branches,
can limit the chosen revision to one within a specific date. An optional date is specified by adding a
colon (:) to the tag: -jSymbolic_Tag:Date_Specifier.
See node 'Branching and merging' in the CVS manual.
-N
Only useful together with -d dir. With this option, cvs will not ``shorten'' module paths in your
working directory when you check out a single module. See the -d flag for examples and a discussion.
-s
Like -c, but include the status of all modules, and sort it by the status string. See node 'modules'
in the CVS manual, for info about the -s option that is used inside the modules file to set the module
status.
checkout examples
Get a copy of the module tc:
$ cvs checkout tc
Get a copy of the module tc as it looked one day ago:
$ cvs checkout -D yesterday tc
commit
Check files into the repository
• Synopsis: commit [-lnRf] [-m 'log_message' | -F file] [-r revision] [files...]
• Requires: working directory, repository.
• Changes: repository.
• Synonym: ci
Use commit when you want to incorporate changes from your working source files into the source
repository.
If you don't specify particular files to commit, all of the files in your working current directory are
examined. commit is careful to change in the repository only those files that you have really changed.
By default (or if you explicitly specify the -R option), files in subdirectories are also examined and
committed if they have changed; you can use the -l option to limit commit to the current directory
only.
commit verifies that the selected files are up to date with the current revisions in the source
repository; it will notify you, and exit without committing, if any of the specified files must be made
current first with update (see node 'update' in the CVS manual). commit does not call the update
command for you, but rather leaves that for you to do when the time is right.
When all is well, an editor is invoked to allow you to enter a log message that will be written to one
or more logging programs (see node 'modules' in the CVS manual, and see node 'loginfo' in the CVS
manual) and placed in the rcs file inside the repository. This log message can be retrieved with the
log command; see node 'log' in the CVS manual. You can specify the log message on the command line
with the -m message option, and thus avoid the editor invocation, or use the -F file option to specify
that the argument file contains the log message.
At commit, a unique commitid is placed in the rcs file inside the repository. All files committed at
once get the same commitid, a string consisting only of hexadecimal digits (usually 16 in GNU cvs, 19
in MirBSD and MirDebian GNU cvs). FSF GNU cvs 1.11, MirOS GNU cvs 1.11, and OpenBSD OpenCVS do not
support commitids yet. The commitid can be retrieved with the log and status command; see node 'log'
in the CVS manual and node 'File status' in the CVS manual.
commit options
These standard options are supported by commit (see node 'Common options' in the CVS manual, for a
complete description of them):
-l
Local; run only in current working directory.
-R
Commit directories recursively. This is on by default.
-r revision
Commit to revision. revision must be either a branch, or a revision on the main trunk that is higher
than any existing revision number (see node 'Assigning revisions' in the CVS manual). You cannot
commit to a specific revision on a branch.
commit also supports these options:
-c
Refuse to commit files unless the user has registered a valid edit on the file via cvs edit. This is
most useful when commit -c and edit -c have been placed in all .cvsrc files. A commit can be forced
anyways by either regestering an edit retroactively via cvs edit (no changes to the file will be lost)
or using the -f option to commit. Support for commit -c requires both client and a server versions
1.12.10 or greater.
-F file
Read the log message from file, instead of invoking an editor.
-f
Note that this is not the standard behavior of the -f option as defined in node 'Common options' in the
CVS manual.
Force cvs to commit a new revision even if you haven't made any changes to the file. As of cvs version
1.12.10, it also causes the -c option to be ignored. If the current revision of file is 1.7, then the
following two commands are equivalent:
$ cvs commit -f file
$ cvs commit -r 1.8 file
The -f option disables recursion (i.e., it implies -l). To force cvs to commit a new revision for all
files in all subdirectories, you must use -f -R.
-m message
Use message as the log message, instead of invoking an editor.
commit examples
Committing to a branch
You can commit to a branch revision (one that has an even number of dots) with the -r option. To create
a branch revision, use the -b option of the rtag or tag commands (see node 'Branching and merging' in the
CVS manual). Then, either checkout or update can be used to base your sources on the newly created
branch. From that point on, all commit changes made within these working sources will be automatically
added to a branch revision, thereby not disturbing main-line development in any way. For example, if you
had to create a patch to the 1.2 version of the product, even though the 2.0 version is already under
development, you might do:
$ cvs rtag -b -r FCS1_2 FCS1_2_Patch product_module
$ cvs checkout -r FCS1_2_Patch product_module
$ cd product_module
[[ hack away ]]
$ cvs commit
This works automatically since the -r option is sticky.
Creating the branch after editing
Say you have been working on some extremely experimental software, based on whatever revision you
happened to checkout last week. If others in your group would like to work on this software with you,
but without disturbing main-line development, you could commit your change to a new branch. Others can
then checkout your experimental stuff and utilize the full benefit of cvs conflict resolution. The
scenario might look like:
[[ hacked sources are present ]]
$ cvs tag -b EXPR1
$ cvs update -r EXPR1
$ cvs commit
The update command will make the -r EXPR1 option sticky on all files. Note that your changes to the
files will never be removed by the update command. The commit will automatically commit to the correct
branch, because the -r is sticky. You could also do like this:
[[ hacked sources are present ]]
$ cvs tag -b EXPR1
$ cvs commit -r EXPR1
but then, only those files that were changed by you will have the -r EXPR1 sticky flag. If you hack
away, and commit without specifying the -r EXPR1 flag, some files may accidentally end up on the main
trunk.
To work with you on the experimental change, others would simply do
$ cvs checkout -r EXPR1 whatever_module
diff
Show differences between revisions
• Synopsis: diff [-lR] [-k kflag] [format_options] [(-r rev1[:date1] | -D date1) [-r rev2[:date2] | -D
date2]] [files...]
• Requires: working directory, repository.
• Changes: nothing.
The diff command is used to compare different revisions of files. The default action is to compare
your working files with the revisions they were based on, and report any differences that are found.
If any file names are given, only those files are compared. If any directories are given, all files
under them will be compared.
The exit status for diff is different than for other cvs commands; for details see node 'Exit status'
in the CVS manual.
diff options
These standard options are supported by diff (see node 'Common options' in the CVS manual, for a complete
description of them):
-D date
Use the most recent revision no later than date. See -r for how this affects the comparison.
-k kflag
Process keywords according to kflag. See node 'Keyword substitution' in the CVS manual.
-l
Local; run only in current working directory.
-R
Examine directories recursively. This option is on by default.
-r tag[:date]
Compare with revision specified by tag or, when date is specified and tag is a branch tag, the version
from the branch tag as it existed on date. Zero, one or two -r options can be present. With no -r
option, the working file will be compared with the revision it was based on. With one -r, that
revision will be compared to your current working file. With two -r options those two revisions will
be compared (and your working file will not affect the outcome in any way).
One or both -r options can be replaced by a -D date option, described above.
The following options specify the format of the output. They have the same meaning as in GNU diff.
Most options have two equivalent names, one of which is a single letter preceded by -, and the other of
which is a long name preceded by --.
-lines
Show lines (an integer) lines of context. This option does not specify an output format by itself; it
has no effect unless it is combined with -c or -u. This option is obsolete. For proper operation,
patch typically needs at least two lines of context.
-a
Treat all files as text and compare them line-by-line, even if they do not seem to be text.
-b
Ignore trailing white space and consider all other sequences of one or more white space characters to
be equivalent.
-B
Ignore changes that just insert or delete blank lines.
--binary
Read and write data in binary mode.
--brief
Report only whether the files differ, not the details of the differences.
-c
Use the context output format.
-C lines
--context[=lines]
Use the context output format, showing lines (an integer) lines of context, or three if lines is not
given. For proper operation, patch typically needs at least two lines of context.
--changed-group-format=format
Use format to output a line group containing differing lines from both files in if-then-else format.
See node 'Line group formats' in the CVS manual.
-d
Change the algorithm to perhaps find a smaller set of changes. This makes diff slower (sometimes much
slower).
-e
--ed
Make output that is a valid ed script.
--expand-tabs
Expand tabs to spaces in the output, to preserve the alignment of tabs in the input files.
-f
Make output that looks vaguely like an ed script but has changes in the order they appear in the file.
-F regexp
In context and unified format, for each hunk of differences, show some of the last preceding line that
matches regexp.
--forward-ed
Make output that looks vaguely like an ed script but has changes in the order they appear in the file.
-H
Use heuristics to speed handling of large files that have numerous scattered small changes.
--horizon-lines=lines
Do not discard the last lines lines of the common prefix and the first lines lines of the common
suffix.
-i
Ignore changes in case; consider upper- and lower-case letters equivalent.
-I regexp
Ignore changes that just insert or delete lines that match regexp.
--ifdef=name
Make merged if-then-else output using name.
--ignore-all-space
Ignore white space when comparing lines.
--ignore-blank-lines
Ignore changes that just insert or delete blank lines.
--ignore-case
Ignore changes in case; consider upper- and lower-case to be the same.
--ignore-matching-lines=regexp
Ignore changes that just insert or delete lines that match regexp.
--ignore-space-change
Ignore trailing white space and consider all other sequences of one or more white space characters to
be equivalent.
--initial-tab
Output a tab rather than a space before the text of a line in normal or context format. This causes
the alignment of tabs in the line to look normal.
-L label
Use label instead of the file name in the context format and unified format headers.
--label=label
Use label instead of the file name in the context format and unified format headers.
--left-column
Print only the left column of two common lines in side by side format.
--line-format=format
Use format to output all input lines in if-then-else format. See node 'Line formats' in the CVS
manual.
--minimal
Change the algorithm to perhaps find a smaller set of changes. This makes diff slower (sometimes much
slower).
-n
Output RCS-format diffs; like -f except that each command specifies the number of lines affected.
-N
--new-file
In directory comparison, if a file is found in only one directory, treat it as present but empty in the
other directory.
--new-group-format=format
Use format to output a group of lines taken from just the second file in if-then-else format. See node
'Line group formats' in the CVS manual.
--new-line-format=format
Use format to output a line taken from just the second file in if-then-else format. See node 'Line
formats' in the CVS manual.
--old-group-format=format
Use format to output a group of lines taken from just the first file in if-then-else format. See node
'Line group formats' in the CVS manual.
--old-line-format=format
Use format to output a line taken from just the first file in if-then-else format. See node 'Line
formats' in the CVS manual.
-p
Show which C function each change is in.
--rcs
Output RCS-format diffs; like -f except that each command specifies the number of lines affected.
--report-identical-files
-s
Report when two files are the same.
--show-c-function
Show which C function each change is in.
--show-function-line=regexp
In context and unified format, for each hunk of differences, show some of the last preceding line that
matches regexp.
--side-by-side
Use the side by side output format.
--speed-large-files
Use heuristics to speed handling of large files that have numerous scattered small changes.
--suppress-common-lines
Do not print common lines in side by side format.
-t
Expand tabs to spaces in the output, to preserve the alignment of tabs in the input files.
-T
Output a tab rather than a space before the text of a line in normal or context format. This causes
the alignment of tabs in the line to look normal.
--text
Treat all files as text and compare them line-by-line, even if they do not appear to be text.
-u
Use the unified output format.
--unchanged-group-format=format
Use format to output a group of common lines taken from both files in if-then-else format. See node
'Line group formats' in the CVS manual.
--unchanged-line-format=format
Use format to output a line common to both files in if-then-else format. See node 'Line formats' in
the CVS manual.
-U lines
--unified[=lines]
Use the unified output format, showing lines (an integer) lines of context, or three if lines is not
given. For proper operation, patch typically needs at least two lines of context.
-w
Ignore white space when comparing lines.
-W columns
--width=columns
Use an output width of columns in side by side format.
-y
Use the side by side output format.
Line group formats
Line group formats let you specify formats suitable for many applications that allow if-then-else input,
including programming languages and text formatting languages. A line group format specifies the output
format for a contiguous group of similar lines.
For example, the following command compares the TeX file myfile with the original version from the
repository, and outputs a merged file in which old regions are surrounded by \begin{em}-\end{em} lines,
and new regions are surrounded by \begin{bf}-\end{bf} lines.
cvs diff \
--old-group-format='\begin{em}
%<\end{em}
' \
--new-group-format='\begin{bf}
%>\end{bf}
' \
myfile
The following command is equivalent to the above example, but it is a little more verbose, because it
spells out the default line group formats.
cvs diff \
--old-group-format='\begin{em}
%<\end{em}
' \
--new-group-format='\begin{bf}
%>\end{bf}
' \
--unchanged-group-format='%=' \
--changed-group-format='\begin{em}
%<\end{em}
\begin{bf}
%>\end{bf}
' \
myfile
Here is a more advanced example, which outputs a diff listing with headers containing line numbers in a
``plain English'' style.
cvs diff \
--unchanged-group-format='' \
--old-group-format='-------- %dn line%(n=1?:s) deleted at %df:
%<' \
--new-group-format='-------- %dN line%(N=1?:s) added after %de:
%>' \
--changed-group-format='-------- %dn line%(n=1?:s) changed at %df:
%<-------- to:
%>' \
myfile
To specify a line group format, use one of the options listed below. You can specify up to four line
group formats, one for each kind of line group. You should quote format, because it typically contains
shell metacharacters.
--old-group-format=format
These line groups are hunks containing only lines from the first file. The default old group format is
the same as the changed group format if it is specified; otherwise it is a format that outputs the line
group as-is.
--new-group-format=format
These line groups are hunks containing only lines from the second file. The default new group format
is same as the changed group format if it is specified; otherwise it is a format that outputs the line
group as-is.
--changed-group-format=format
These line groups are hunks containing lines from both files. The default changed group format is the
concatenation of the old and new group formats.
--unchanged-group-format=format
These line groups contain lines common to both files. The default unchanged group format is a format
that outputs the line group as-is.
In a line group format, ordinary characters represent themselves; conversion specifications start with
% and have one of the following forms.
%<
stands for the lines from the first file, including the trailing newline. Each line is formatted
according to the old line format (see node 'Line formats' in the CVS manual).
%>
stands for the lines from the second file, including the trailing newline. Each line is formatted
according to the new line format.
%=
stands for the lines common to both files, including the trailing newline. Each line is formatted
according to the unchanged line format.
%%
stands for %.
%c'C'
where C is a single character, stands for C. C may not be a backslash or an apostrophe. For example,
%c':' stands for a colon, even inside the then-part of an if-then-else format, which a colon would
normally terminate.
%c'\O'
where O is a string of 1, 2, or 3 octal digits, stands for the character with octal code O. For
example, %c'\0' stands for a null character.
Fn
where F is a printf conversion specification and n is one of the following letters, stands for n's
value formatted with F.
e
The line number of the line just before the group in the old file.
f
The line number of the first line in the group in the old file; equals e + 1.
l
The line number of the last line in the group in the old file.
m
The line number of the line just after the group in the old file; equals l + 1.
n
The number of lines in the group in the old file; equals l - f + 1.
E, F, L, M, N
Likewise, for lines in the new file.
The printf conversion specification can be %d, %o, %x, or %X, specifying decimal, octal, lower case
hexadecimal, or upper case hexadecimal output respectively. After the % the following options can
appear in sequence: a - specifying left-justification; an integer specifying the minimum field width;
and a period followed by an optional integer specifying the minimum number of digits. For example,
%5dN prints the number of new lines in the group in a field of width 5 characters, using the printf
format "%5d".
(A=B?T:E)
If A equals B then T else E. A and B are each either a decimal constant or a single letter interpreted
as above. This format spec is equivalent to T if A's value equals B's; otherwise it is equivalent to
E.
For example, %(N=0?no:%dN) line%(N=1?:s) is equivalent to no lines if N (the number of lines in the
group in the new file) is 0, to 1 line if N is 1, and to %dN lines otherwise.
Line formats
Line formats control how each line taken from an input file is output as part of a line group in
if-then-else format.
For example, the following command outputs text with a one-column change indicator to the left of the
text. The first column of output is - for deleted lines, | for added lines, and a space for unchanged
lines. The formats contain newline characters where newlines are desired on output.
cvs diff \
--old-line-format='-%l
' \
--new-line-format='|%l
' \
--unchanged-line-format=' %l
' \
myfile
To specify a line format, use one of the following options. You should quote format, since it often
contains shell metacharacters.
--old-line-format=format
formats lines just from the first file.
--new-line-format=format
formats lines just from the second file.
--unchanged-line-format=format
formats lines common to both files.
--line-format=format
formats all lines; in effect, it sets all three above options simultaneously.
In a line format, ordinary characters represent themselves; conversion specifications start with % and
have one of the following forms.
%l
stands for the contents of the line, not counting its trailing newline (if any). This format ignores
whether the line is incomplete.
%L
stands for the contents of the line, including its trailing newline (if any). If a line is incomplete,
this format preserves its incompleteness.
%%
stands for %.
%c'C'
where C is a single character, stands for C. C may not be a backslash or an apostrophe. For example,
%c':' stands for a colon.
%c'\O'
where O is a string of 1, 2, or 3 octal digits, stands for the character with octal code O. For
example, %c'\0' stands for a null character.
Fn
where F is a printf conversion specification, stands for the line number formatted with F. For
example, %.5dn prints the line number using the printf format "%.5d". See node 'Line group formats' in
the CVS manual, for more about printf conversion specifications.
The default line format is %l followed by a newline character.
If the input contains tab characters and it is important that they line up on output, you should ensure
that %l or %L in a line format is just after a tab stop (e.g. by preceding %l or %L with a tab
character), or you should use the -t or --expand-tabs option.
Taken together, the line and line group formats let you specify many different formats. For example,
the following command uses a format similar to diff's normal format. You can tailor this command to
get fine control over diff's output.
cvs diff \
--old-line-format='< %l
' \
--new-line-format='> %l
' \
--old-group-format='%df%(f=l?:,%dl)d%dE
%<' \
--new-group-format='%dea%dF%(F=L?:,%dL)
%>' \
--changed-group-format='%df%(f=l?:,%dl)c%dF%(F=L?:,%dL)
%<—
%>' \
--unchanged-group-format='' \
myfile
diff examples
The following line produces a Unidiff (-u flag) between revision 1.14 and 1.19 of backend.c. Due to the
-kk flag no keywords are substituted, so differences that only depend on keyword substitution are
ignored.
$ cvs diff -kk -u -r 1.14 -r 1.19 backend.c
Suppose the experimental branch EXPR1 was based on a set of files tagged RELEASE_1_0. To see what has
happened on that branch, the following can be used:
$ cvs diff -r RELEASE_1_0 -r EXPR1
A command like this can be used to produce a context diff between two releases:
$ cvs diff -c -r RELEASE_1_0 -r RELEASE_1_1 > diffs
If you are maintaining ChangeLogs, a command like the following just before you commit your changes may
help you write the ChangeLog entry. All local modifications that have not yet been committed will be
printed.
$ cvs diff -u | less
export
Export sources from CVS, similar to checkout
• Synopsis: export [-flNnR] (-r rev[:date] | -D date) [-k subst] [-d dir] module...
• Requires: repository.
• Changes: current directory.
This command is a variant of checkout; use it when you want a copy of the source for module without the
cvs administrative directories. For example, you might use export to prepare source for shipment
off-site. This command requires that you specify a date or tag (with -D or -r), so that you can count
on reproducing the source you ship to others (and thus it always prunes empty directories).
One often would like to use -kv with cvs export. This causes any keywords to be expanded such that an
import done at some other site will not lose the keyword revision information. But be aware that
doesn't handle an export containing binary files correctly. Also be aware that after having used -kv,
one can no longer use the ident command (which is part of the rcs suite—see ident(1)) which looks for
keyword strings. If you want to be able to use ident you must not use -kv.
export options
These standard options are supported by export (see node 'Common options' in the CVS manual, for a
complete description of them):
-D date
Use the most recent revision no later than date.
-f
If no matching revision is found, retrieve the most recent revision (instead of ignoring the file).
-l
Local; run only in current working directory.
-n
Do not run any checkout program.
-R
Export directories recursively. This is on by default.
-r tag[:date]
Export the revision specified by tag or, when date is specified and tag is a branch tag, the version
from the branch tag as it existed on date. See node 'Common options' in the CVS manual.
In addition, these options (that are common to checkout and export) are also supported:
-d dir
Create a directory called dir for the working files, instead of using the module name. See node
'checkout options' in the CVS manual, for complete details on how cvs handles this flag.
-k subst
Set keyword expansion mode (see node 'Substitution modes' in the CVS manual).
-N
Only useful together with -d dir. See node 'checkout options' in the CVS manual, for complete details
on how cvs handles this flag.
history
Show status of files and users
• Synopsis: history [-report] [-flags] [-options args] [files...]
• Requires: the file $CVSROOT/CVSROOT/history
• Changes: nothing.
cvs can keep a history log that tracks each use of most cvs commands. You can use history to display
this information in various formats.
To enable logging, the LogHistory config option must be set to some value other than the empty string
and the history file specified by the HistoryLogPath option must be writable by all users who may run
the cvs executable (see node 'config' in the CVS manual).
To enable the history command, logging must be enabled as above and the HistorySearchPath config option
(see node 'config' in the CVS manual) must be set to specify some number of the history logs created
thereby and these files must be readable by each user who might run the history command.
Creating a repository via the cvs init command will enable logging of all possible events to a single
history log file ($CVSROOT/CVSROOT/history) with read and write permissions for all users (see node
'Creating a repository' in the CVS manual).
Note: history uses -f, -l, -n, and -p in ways that conflict with the normal use inside cvs (see node
'Common options' in the CVS manual).
history options
Several options (shown above as -report) control what kind of report is generated:
-c
Report on each time commit was used (i.e., each time the repository was modified).
-e
Everything (all record types). Equivalent to specifying -x with all record types. Of course, -e will
also include record types which are added in a future version of cvs; if you are writing a script which
can only handle certain record types, you'll want to specify -x.
-m module
Report on a particular module. (You can meaningfully use -m more than once on the command line.)
-o
Report on checked-out modules. This is the default report type.
-T
Report on all tags.
-x type
Extract a particular set of record types type from the cvs history. The types are indicated by single
letters, which you may specify in combination.
Certain commands have a single record type:
F
release
O
checkout
E
export
T
rtag
One of five record types may result from an update:
C
A merge was necessary but collisions were detected (requiring manual merging).
G
A merge was necessary and it succeeded.
U
A working file was copied from the repository.
P
A working file was patched to match the repository.
W
The working copy of a file was deleted during update (because it was gone from the repository).
One of three record types results from commit:
A
A file was added for the first time.
M
A file was modified.
R
A file was removed.
The options shown as -flags constrain or expand the report without requiring option arguments:
-a
Show data for all users (the default is to show data only for the user executing history).
-l
Show last modification only.
-w
Show only the records for modifications done from the same working directory where history is
executing.
The options shown as -options args constrain the report based on an argument:
-b str
Show data back to a record containing the string str in either the module name, the file name, or
the repository path.
-D date
Show data since date. This is slightly different from the normal use of -D date, which selects the
newest revision older than date.
-f file
Show data for a particular file (you can specify several -f options on the same command line). This is
equivalent to specifying the file on the command line.
-n module
Show data for a particular module (you can specify several -n options on the same command line).
-p repository
Show data for a particular source repository (you can specify several -p options on the same command
line).
-r rev
Show records referring to revisions since the revision or tag named rev appears in individual rcs
files. Each rcs file is searched for the revision or tag.
-t tag
Show records since tag tag was last added to the history file. This differs from the -r flag above in
that it reads only the history file, not the rcs files, and is much faster.
-u name
Show records for user name.
-z timezone
Show times in the selected records using the specified time zone instead of UTC.
import
Import sources into CVS, using vendor branches
• Synopsis: import [-options] repository vendortag releasetag...
• Requires: Repository, source distribution directory.
• Changes: repository.
Use import to incorporate an entire source distribution from an outside source (e.g., a source vendor)
into your source repository directory. You can use this command both for initial creation of a
repository, and for wholesale updates to the module from the outside source. See node 'Tracking
sources' in the CVS manual, for a discussion on this subject.
The repository argument gives a directory name (or a path to a directory) under the cvs root directory
for repositories; if the directory did not exist, import creates it.
When you use import for updates to source that has been modified in your source repository (since a
prior import), it will notify you of any files that conflict in the two branches of development; use
checkout -j to reconcile the differences, as import instructs you to do.
If cvs decides a file should be ignored (see node 'cvsignore' in the CVS manual), it does not import it
and prints I followed by the filename (see node 'import output' in the CVS manual, for a complete
description of the output).
If the file $CVSROOT/CVSROOT/cvswrappers exists, any file whose names match the specifications in that
file will be treated as packages and the appropriate filtering will be performed on the file/directory
before being imported. See node 'Wrappers' in the CVS manual.
The outside source is saved in a first-level branch, by default 1.1.1. Updates are leaves of this
branch; for example, files from the first imported collection of source will be revision 1.1.1.1, then
files from the first imported update will be revision 1.1.1.2, and so on.
At least three arguments are required. repository is needed to identify the collection of source.
vendortag is a tag for the entire branch (e.g., for 1.1.1). You must also specify at least one
releasetag to uniquely identify the files at the leaves created each time you execute import. The
releasetag should be new, not previously existing in the repository file, and uniquely identify the
imported release,
Note that import does not change the directory in which you invoke it. In particular, it does not set
up that directory as a cvs working directory; if you want to work with the sources import them first
and then check them out into a different directory (see node 'Getting the source' in the CVS manual).
import options
This standard option is supported by import (see node 'Common options' in the CVS manual, for a complete
description):
-m message
Use message as log information, instead of invoking an editor.
There are the following additional special options.
-b branch
See node 'Multiple vendor branches' in the CVS manual.
-k subst
Indicate the keyword expansion mode desired. This setting will apply to all files created during the
import, but not to any files that previously existed in the repository. See node 'Substitution modes'
in the CVS manual, for a list of valid -k settings.
-I name
Specify file names that should be ignored during import. You can use this option repeatedly. To avoid
ignoring any files at all (even those ignored by default), specify `-I !'.
name can be a file name pattern of the same type that you can specify in the .cvsignore file. See node
'cvsignore' in the CVS manual.
-W spec
Specify file names that should be filtered during import. You can use this option repeatedly.
spec can be a file name pattern of the same type that you can specify in the .cvswrappers file. See
node 'Wrappers' in the CVS manual.
-X
Modify the algorithm used by cvs when importing new files so that new files do not immediately appear
on the main trunk.
Specifically, this flag causes cvs to mark new files as if they were deleted on the main trunk, by
taking the following steps for each file in addition to those normally taken on import: creating a new
revision on the main trunk indicating that the new file is dead, resetting the new file's default
branch, and placing the file in the Attic (see node 'Attic' in the CVS manual) directory.
Use of this option can be forced on a repository-wide basis by setting the
ImportNewFilesToVendorBranchOnly option in CVSROOT/config (see node 'config' in the CVS manual).
import output
import keeps you informed of its progress by printing a line for each file, preceded by one character
indicating the status of the file:
U file
The file already exists in the repository and has not been locally modified; a new revision has been
created (if necessary).
N file
The file is a new file which has been added to the repository.
C file
The file already exists in the repository but has been locally modified; you will have to merge the
changes.
I file
The file is being ignored (see node 'cvsignore' in the CVS manual).
L file
The file is a symbolic link; cvs import ignores symbolic links. People periodically suggest that this
behavior should be changed, but if there is a consensus on what it should be changed to, it is not
apparent. (Various options in the modules file can be used to recreate symbolic links on checkout,
update, etc.; see node 'modules' in the CVS manual.)
import examples
See node 'Tracking sources' in the CVS manual, and node 'From files' in the CVS manual.
log
Print out log information for files
• Synopsis: log [options] [files...]
• Requires: repository, working directory.
• Changes: nothing.
Display log information for files. log used to call the rcs utility rlog. Although this is no longer
true in the current sources, this history determines the format of the output and the options, which
are not quite in the style of the other cvs commands.
The output includes the location of the rcs file, the head revision (the latest revision on the trunk),
all symbolic names (tags) and some other things. For each revision, the revision number, the date, the
author, the number of lines added/deleted, the commitid and the log message are printed. All dates are
displayed in local time at the client. This is typically specified in the $TZ environment variable,
which can be set to govern how log displays dates.
Note: log uses -R in a way that conflicts with the normal use inside cvs (see node 'Common options' in
the CVS manual).
log options
By default, log prints all information that is available. All other options restrict the output. Note
that the revision selection options (-d, -r, -s, and -w) have no effect, other than possibly causing a
search for files in Attic directories, when used in conjunction with the options that restrict the output
to only log header fields (-b, -h, -R, and -t) unless the -S option is also specified.
-b
Print information about the revisions on the default branch, normally the highest branch on the trunk.
-d dates
Print information about revisions with a checkin date/time in the range given by the
semicolon-separated list of dates. The date formats accepted are those accepted by the -D option to
many other cvs commands (see node 'Common options' in the CVS manual). Dates can be combined into
ranges as follows:
d1<d2
d2>d1
Select the revisions that were deposited between d1 and d2.
<d
d>
Select all revisions dated d or earlier.
d<
>d
Select all revisions dated d or later.
d
Select the single, latest revision dated d or earlier.
The > or < characters may be followed by = to indicate an inclusive range rather than an exclusive
one.
Note that the separator is a semicolon (;).
-h
Print only the name of the rcs file, name of the file in the working directory, head, default branch,
access list, locks, symbolic names, and suffix.
-l
Local; run only in current working directory. (Default is to run recursively).
-N
Do not print the list of tags for this file. This option can be very useful when your site uses a lot
of tags, so rather than "more"'ing over 3 pages of tag information, the log information is presented
without tags at all.
-R
Print only the name of the rcs file.
-rrevisions
Print information about revisions given in the comma-separated list revisions of revisions and ranges.
The following table explains the available range formats:
rev1:rev2
Revisions rev1 to rev2 (which must be on the same branch).
rev1::rev2
The same, but excluding rev1.
:rev
::rev
Revisions from the beginning of the branch up to and including rev.
rev:
Revisions starting with rev to the end of the branch containing rev.
rev::
Revisions starting just after rev to the end of the branch containing rev.
branch
An argument that is a branch means all revisions on that branch.
branch1:branch2
branch1::branch2
A range of branches means all revisions on the branches in that range.
branch.
The latest revision in branch.
A bare -r with no revisions means the latest revision on the default branch, normally the trunk.
There can be no space between the -r option and its argument.
-S
Suppress the header if no revisions are selected.
-s states
Print information about revisions whose state attributes match one of the states given in the
comma-separated list states. Individual states may be any text string, though cvs commonly only uses
two states, Exp and dead. See node 'admin options' in the CVS manual for more information.
-t
Print the same as -h, plus the descriptive text.
-wlogins
Print information about revisions checked in by users with login names appearing in the comma-separated
list logins. If logins is omitted, the user's login is assumed. There can be no space between the -w
option and its argument.
log prints the intersection of the revisions selected with the options -d, -s, and -w, intersected with
the union of the revisions selected by -b and -r.
log examples
Since log shows dates in local time, you might want to see them in Coordinated Universal Time (UTC) or
some other timezone. To do this you can set your $TZ environment variable before invoking cvs:
$ TZ=UTC cvs log foo.c
$ TZ=EST cvs log bar.c
(If you are using a csh-style shell, like tcsh, you would need to prefix the examples above with env.)
ls & rls
• ls [-e | -l] [-RP] [-r tag[:date]] [-D date] [path...]
• Requires: repository for rls, repository & working directory for ls.
• Changes: nothing.
• Synonym: dir & list are synonyms for ls and rdir & rlist are synonyms for rls.
The ls and rls commands are used to list files and directories in the repository.
By default ls lists the files and directories that belong in your working directory, what would be
there after an update.
By default rls lists the files and directories on the tip of the trunk in the topmost directory of the
repository.
Both commands accept an optional list of file and directory names, relative to the working directory
for ls and the topmost directory of the repository for rls. Neither is recursive by default.
ls & rls options
These standard options are supported by ls & rls:
-d
Show dead revisions (with tag when specified).
-e
Display in CVS/Entries format. This format is meant to remain easily parsable by automation.
-l
Display all details.
-P
Don't list contents of empty directories when recursing.
-R
List recursively.
-r tag[:date]
Show files specified by tag or, when date is specified and tag is a branch tag, the version from the
branch tag as it existed on date. See node 'Common options' in the CVS manual.
-D date
Show files from date.
rls examples
$ cvs rls
cvs rls: Listing module: `.'
CVSROOT
first-dir
$ cvs rls CVSROOT
cvs rls: Listing module: `CVSROOT'
checkoutlist
commitinfo
config
cvswrappers
loginfo
modules
notify
rcsinfo
taginfo
verifymsg
rdiff
'patch' format diffs between releases
• rdiff [-flags] [-V vn] (-r tag1[:date1] | -D date1) [-r tag2[:date2] | -D date2] modules...
• Requires: repository.
• Changes: nothing.
• Synonym: patch
Builds a Larry Wall format patch(1) file between two releases, that can be fed directly into the patch
program to bring an old release up-to-date with the new release. (This is one of the few cvs commands
that operates directly from the repository, and doesn't require a prior checkout.) The diff output is
sent to the standard output device.
You can specify (using the standard -r and -D options) any combination of one or two revisions or
dates. If only one revision or date is specified, the patch file reflects differences between that
revision or date and the current head revisions in the rcs file.
Note that if the software release affected is contained in more than one directory, then it may be
necessary to specify the -p option to the patch command when patching the old sources, so that patch is
able to find the files that are located in other directories.
rdiff options
These standard options are supported by rdiff (see node 'Common options' in the CVS manual, for a
complete description of them):
-D date
Use the most recent revision no later than date.
-f
If no matching revision is found, retrieve the most recent revision (instead of ignoring the file).
-k kflag
Process keywords according to kflag. See node 'Keyword substitution' in the CVS manual.
-l
Local; don't descend subdirectories.
-R
Examine directories recursively. This option is on by default.
-r tag
Use the revision specified by tag, or when date is specified and tag is a branch tag, the version from
the branch tag as it existed on date. See node 'Common options' in the CVS manual.
In addition to the above, these options are available:
-c
Use the context diff format. This is the default format.
-p
Show which C function each change is in.
-s
Create a summary change report instead of a patch. The summary includes information about files that
were changed or added between the releases. It is sent to the standard output device. This is useful
for finding out, for example, which files have changed between two dates or revisions.
-t
A diff of the top two revisions is sent to the standard output device. This is most useful for seeing
what the last change to a file was.
-u
Use the unidiff format for the context diffs. Remember that old versions of the patch program can't
handle the unidiff format, so if you plan to post this patch to the net you should probably not use -u.
-V vn
Expand keywords according to the rules current in rcs version vn (the expansion format changed with rcs
version 5). Note that this option is no longer accepted. cvs will always expand keywords the way that
rcs version 5 does.
rdiff examples
Suppose you receive mail from foo@example.net asking for an update from release 1.2 to 1.4 of the tc
compiler. You have no such patches on hand, but with cvs that can easily be fixed with a command such as
this:
$ cvs rdiff -c -r FOO1_2 -r FOO1_4 tc | \
$$ Mail -s 'The patches you asked for' foo@example.net
Suppose you have made release 1.3, and forked a branch called R_1_3fix for bug fixes. R_1_3_1
corresponds to release 1.3.1, which was made some time ago. Now, you want to see how much development
has been done on the branch. This command can be used:
$ cvs patch -s -r R_1_3_1 -r R_1_3fix module-name
cvs rdiff: Diffing module-name
File ChangeLog,v changed from revision 1.52.2.5 to 1.52.2.6
File foo.c,v changed from revision 1.52.2.3 to 1.52.2.4
File bar.h,v changed from revision 1.29.2.1 to 1.2
release
Indicate that a Module is no longer in use
• release [-d] directories...
• Requires: Working directory.
• Changes: Working directory, history log.
This command is meant to safely cancel the effect of cvs checkout. Since cvs doesn't lock files, it
isn't strictly necessary to use this command. You can always simply delete your working directory, if
you like; but you risk losing changes you may have forgotten, and you leave no trace in the cvs history
file (see node 'history file' in the CVS manual) that you've abandoned your checkout.
Use cvs release to avoid these problems. This command checks that no uncommitted changes are present;
that you are executing it from immediately above a cvs working directory; and that the repository
recorded for your files is the same as the repository defined in the module database.
If all these conditions are true, cvs release leaves a record of its execution (attesting to your
intentionally abandoning your checkout) in the cvs history log.
release options
The release command supports one command option:
-d
Delete your working copy of the file if the release succeeds. If this flag is not given your files
will remain in your working directory.
WARNING: The release command deletes all directories and files recursively. This has the very serious
side-effect that any directory that you have created inside your checked-out sources, and not added to
the repository (using the add command; see node 'Adding files' in the CVS manual) will be silently
deleted—even if it is non-empty!
release output
Before release releases your sources it will print a one-line message for any file that is not
up-to-date.
U file
P file
There exists a newer revision of this file in the repository, and you have not modified your local copy
of the file (U and P mean the same thing).
A file
The file has been added to your private copy of the sources, but has not yet been committed to the
repository. If you delete your copy of the sources this file will be lost.
R file
The file has been removed from your private copy of the sources, but has not yet been removed from the
repository, since you have not yet committed the removal. See node 'commit' in the CVS manual.
M file
The file is modified in your working directory. There might also be a newer revision inside the
repository.
? file
file is in your working directory, but does not correspond to anything in the source repository, and is
not in the list of files for cvs to ignore (see the description of the -I option, and see node
'cvsignore' in the CVS manual). If you remove your working sources, this file will be lost.
release examples
Release the tc directory, and delete your local working copy of the files.
$ cd .. # You must stand immediately above the
# sources when you issue cvs release.
$ cvs release -d tc
You have [0] altered files in this repository.
Are you sure you want to release (and delete) directory `tc': y
$
server & pserver
Act as a server for a client on stdin/stdout
• pserver [-c path]
server [-c path]
• Requires: repository, client conversation on stdin/stdout
• Changes: Repository or, indirectly, client working directory.
The cvs server and pserver commands are used to provide repository access to remote clients and expect
a client conversation on stdin & stdout. Typically these commands are launched from inetd or via ssh
(see node 'Remote repositories' in the CVS manual).
server expects that the client has already been authenticated somehow, typically via ssh, and pserver
attempts to authenticate the client itself.
Only one option is available with the server and pserver commands:
-c path
Load configuration from path rather than the default location $CVSROOT/CVSROOT/config (see node
'config' in the CVS manual). path must be /etc/cvs.conf or prefixed by /etc/cvs/. This option is
supported beginning with cvs release 1.12.13.
suck
Download RCS ,v file raw
• suck module/path
• Requires: repository
Locates the file module/path,v or module/pa/Attic/th,v and downloads it raw as RCS comma-v file.
Output consists of the real pathname of the comma-v file, relative to the CVS repository, followed by a
newline and the binary file content immediately thereafter.
update
Bring work tree in sync with repository
• update [-ACdflPpR] [-I name] [-j rev [-j rev]] [-k kflag] [-r tag[:date] | -D date] [-W spec] files...
• Requires: repository, working directory.
• Changes: working directory.
After you've run checkout to create your private copy of source from the common repository, other
developers will continue changing the central source. From time to time, when it is convenient in your
development process, you can use the update command from within your working directory to reconcile
your work with any revisions applied to the source repository since your last checkout or update.
Without the -C option, update will also merge any differences between the local copy of files and their
base revisions into any destination revisions specified with -r, -D, or -A.
update options
These standard options are available with update (see node 'Common options' in the CVS manual, for a
complete description of them):
-D date
Use the most recent revision no later than date. This option is sticky, and implies -P. See node
'Sticky tags' in the CVS manual, for more information on sticky tags/dates.
-f
Only useful with the -D or -r flags. If no matching revision is found, retrieve the most recent
revision (instead of ignoring the file).
-k kflag
Process keywords according to kflag. See node 'Keyword substitution' in the CVS manual. This option
is sticky; future updates of this file in this working directory will use the same kflag. The status
command can be viewed to see the sticky options. See node 'Invoking CVS' in the CVS manual, for more
information on the status command.
-l
Local; run only in current working directory. See node 'Recursive behavior' in the CVS manual.
-P
Prune empty directories. See node 'Moving directories' in the CVS manual.
-p
Pipe files to the standard output.
-R
Update directories recursively (default). See node 'Recursive behavior' in the CVS manual.
-r tag[:date]
Retrieve the revisions specified by tag or, when date is specified and tag is a branch tag, the version
from the branch tag as it existed on date. This option is sticky, and implies -P. See node 'Sticky
tags' in the CVS manual, for more information on sticky tags/dates. Also see node 'Common options' in
the CVS manual.
These special options are also available with update.
-A
Reset any sticky tags, dates, or -k options. See node 'Sticky tags' in the CVS manual, for more
information on sticky tags/dates.
-C
Overwrite locally modified files with clean copies from the repository (the modified file is saved in
.#file.revision, however).
-d
Create any directories that exist in the repository if they're missing from the working directory.
Normally, update acts only on directories and files that were already enrolled in your working
directory.
This is useful for updating directories that were created in the repository since the initial checkout;
but it has an unfortunate side effect. If you deliberately avoided certain directories in the
repository when you created your working directory (either through use of a module name or by listing
explicitly the files and directories you wanted on the command line), then updating with -d will create
those directories, which may not be what you want.
-I name
Ignore files whose names match name (in your working directory) during the update. You can specify -I
more than once on the command line to specify several files to ignore. Use -I ! to avoid ignoring any
files at all. See node 'cvsignore' in the CVS manual, for other ways to make cvs ignore some files.
-Wspec
Specify file names that should be filtered during update. You can use this option repeatedly.
spec can be a file name pattern of the same type that you can specify in the .cvswrappers file. See
node 'Wrappers' in the CVS manual.
-jrevision
With two -j options, merge changes from the revision specified with the first -j option to the revision
specified with the second j option, into the working directory.
With one -j option, merge changes from the ancestor revision to the revision specified with the -j
option, into the working directory. The ancestor revision is the common ancestor of the revision which
the working directory is based on, and the revision specified in the -j option.
Note that using a single -j tagname option rather than -j branchname to merge changes from a branch
will often not remove files which were removed on the branch. See node 'Merging adds and removals' in
the CVS manual, for more.
In addition, each -j option can contain an optional date specification which, when used with branches,
can limit the chosen revision to one within a specific date. An optional date is specified by adding a
colon (:) to the tag: -jSymbolic_Tag:Date_Specifier.
See node 'Branching and merging' in the CVS manual.
update output
update and checkout keep you informed of their progress by printing a line for each file, preceded by one
character indicating the status of the file:
U file
The file was brought up to date with respect to the repository. This is done for any file that exists
in the repository but not in your working directory, and for files that you haven't changed but are not
the most recent versions available in the repository.
P file
Like U, but the cvs server sends a patch instead of an entire file. This accomplishes the same thing
as U using less bandwidth.
A file
The file has been added to your private copy of the sources, and will be added to the source repository
when you run commit on the file. This is a reminder to you that the file needs to be committed.
R file
The file has been removed from your private copy of the sources, and will be removed from the source
repository when you run commit on the file. This is a reminder to you that the file needs to be
committed.
M file
The file is modified in your working directory.
M can indicate one of two states for a file you're working on: either there were no modifications to
the same file in the repository, so that your file remains as you last saw it; or there were
modifications in the repository as well as in your copy, but they were merged successfully, without
conflict, in your working directory.
cvs will print some messages if it merges your work, and a backup copy of your working file (as it
looked before you ran update) will be made. The exact name of that file is printed while update runs.
C file
A conflict was detected while trying to merge your changes to file with changes from the source
repository. file (the copy in your working directory) is now the result of attempting to merge the two
revisions; an unmodified copy of your file is also in your working directory, with the name
.#file.revision where revision is the revision that your modified file started from. Resolve the
conflict as described in node 'Conflicts example' in the CVS manual. (Note that some systems
automatically purge files that begin with .# if they have not been accessed for a few days. If you
intend to keep a copy of your original file, it is a very good idea to rename it.) Under vms, the file
name starts with __ rather than .#.
? file
file is in your working directory, but does not correspond to anything in the source repository, and is
not in the list of files for cvs to ignore (see the description of the -I option, and see node
'cvsignore' in the CVS manual).
AUTHORS
Dick Grune
Original author of the cvs shell script version posted to comp.sources.unix in the volume6 release
of December, 1986. Credited with much of the cvs conflict resolution algorithms.
Brian Berliner
Coder and designer of the cvs program itself in April, 1989, based on the original work done by
Dick.
Jeff Polk
Helped Brian with the design of the cvs module and vendor branch support and author of the
checkin(1) shell script (the ancestor of cvs import).
Larry Jones, Derek R. Price, and Mark D. Baushke
Have helped maintain cvs for many years.
And many others too numerous to mention here.
SEE ALSO
The most comprehensive manual for CVS is Version Management with CVS by Per Cederqvist et al. Depending
on your system, you may be able to get it with the info CVS command or it may be available as cvs.pdf
(Portable Document Format), cvs.ps (PostScript), cvs.texinfo (Texinfo source), or cvs.html.
For CVS updates, more information on documentation, software related to CVS, development of CVS, and
more, see:
http://www.nongnu.org/cvs/
ci(1), co(1), cvs(5), cvsbug(8), diff(1), grep(1), patch(1), rcs(1), rcsdiff(1), rcsmerge(1), rlog(1).
CVS(1)