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|
This is Info file cvsclient.info, produced by Makeinfo-1.63 from the
input file ./cvsclient.texi.
File: cvsclient.info, Node: Top, Next: Introduction, Up: (dir)
CVS Client/Server
*****************
This document describes the client/server protocol used by CVS. It
does not describe how to use or administer client/server CVS; see the
regular CVS manual for that. This is version 1.8.1 of the protocol
specification--*Note Introduction:: for more on what this version number
means.
* Menu:
* Introduction:: What is CVS and what is the client/server protocol for?
* Goals:: Basic design decisions, requirements, scope, etc.
* Notes:: Notes on the current implementation
* Protocol Notes:: Possible enhancements, limitations, etc. of the protocol
* Connection and Authentication:: Various ways to connect to the server
* Protocol:: Complete description of the protocol
File: cvsclient.info, Node: Introduction, Next: Goals, Prev: Top, Up: Top
Introduction
************
CVS is a version control system (with some additional configuration
management functionality). It maintains a central "repository" which
stores files (often source code), including past versions, information
about who modified them and when, and so on. People who wish to look
at or modify those files, known as "developers", use CVS to "check out"
a "working directory" from the repository, to "check in" new versions
of files to the repository, and other operations such as viewing the
modification history of a file. If developers are connected to the
repository by a network, particularly a slow or flaky one, the most
efficient way to use the network is with the CVS-specific protocol
described in this document.
Developers, using the machine on which they store their working
directory, run the CVS "client" program. To perform operations which
cannot be done locally, it connects to the CVS "server" program, which
maintains the repository. For more information on how to connect see
*Note Connection and Authentication::.
This document describes the CVS protocol. Unfortunately, it does not
yet completely document one aspect of the protocol--the detailed
operation of each CVS command and option--and one must look at the CVS
user documentation, `cvs.texinfo', for that information. The protocol
is non-proprietary (anyone who wants to is encouraged to implement it)
and an implementation, known as CVS, is available under the GNU Public
License. The CVS distribution, containing this implementation,
`cvs.texinfo', and a copy (possibly more or less up to date than what
you are reading now) of this document, `cvsclient.texi', can be found
at the usual GNU FTP sites, with a filename such as
`cvs-VERSION.tar.gz'.
This is version 1.8.1 of the protocol specification. This version
number is intended only to aid in distinguishing different versions of
this specification. Although the specification is currently maintained
in conjunction with the CVS implementation, and carries the same
version number, it also intends to document what is involved with
interoperating with other implementations (such as other versions of
CVS); see *Note Requirements::. This version number should not be used
by clients or servers to determine what variant of the protocol to
speak; they should instead use the `valid-requests' and
`Valid-responses' mechanism (*note Protocol::.), which is more flexible.
File: cvsclient.info, Node: Goals, Next: Notes, Prev: Introduction, Up: Top
Goals
*****
* Do not assume any access to the repository other than via this
protocol. It does not depend on NFS, rdist, etc.
* Providing a reliable transport is outside this protocol. It is
expected that it runs over TCP, UUCP, etc.
* Security and authentication are handled outside this protocol (but
see below about `cvs kserver').
* This might be a first step towards adding transactions to CVS
(i.e. a set of operations is either executed atomically or none of
them is executed), improving the locking, or other features. The
current server implementation is a long way from being able to do
any of these things. The protocol, however, is not known to
contain any defects which would preclude them.
* The server never has to have any CVS locks in place while it is
waiting for communication with the client. This makes things
robust in the face of flaky networks.
* Data is transferred in large chunks, which is necessary for good
performance. In fact, currently the client uploads all the data
(without waiting for server responses), and then waits for one
server response (which consists of a massive download of all the
data). There may be cases in which it is better to have a richer
interraction, but the need for the server to release all locks
whenever it waits for the client makes it complicated.
File: cvsclient.info, Node: Notes, Next: Protocol Notes, Prev: Goals, Up: Top
Notes on the Current Implementation
***********************************
The client is built in to the normal `cvs' program, triggered by a
`CVSROOT' variable containing a colon, for example
`cygnus.com:/rel/cvsfiles'.
The client stores what is stored in checked-out directories
(including `CVS'). The way these are stored is totally compatible with
standard CVS. The server requires no storage other than the repository,
which also is totally compatible with standard CVS.
The server is started by `cvs server'. There is no particularly
compelling reason for this rather than making it a separate program
which shares a lot of sources with cvs.
The server can also be started by `cvs kserver', in which case it
does an initial Kerberos authentication on stdin. If the authentication
succeeds, it subsequently runs identically to `cvs server'.
The current server implementation can use up huge amounts of memory
when transmitting a lot of data over a slow link (i.e. the network is
slower than the server can generate the data). There is some
experimental code (see `SERVER_FLOWCONTROL' in options.h) which should
help significantly.
File: cvsclient.info, Node: Protocol Notes, Next: Connection and Authentication, Prev: Notes, Up: Top
Notes on the Protocol
*********************
A number of enhancements are possible:
* The `Modified' request could be speeded up by sending diffs rather
than entire files. The client would need some way to keep the
version of the file which was originally checked out, which would
double client disk space requirements or require coordination with
editors (e.g. maybe it could use emacs numbered backups). This
would also allow local operation of `cvs diff' without arguments.
* Have the client keep a copy of some part of the repository. This
allows all of `cvs diff' and large parts of `cvs update' and `cvs
ci' to be local. The local copy could be made consistent with the
master copy at night (but if the master copy has been updated since
the latest nightly re-sync, then it would read what it needs to
from the master).
* Provide encryption using kerberos.
* The current procedure for `cvs update' is highly sub-optimal if
there are many modified files. One possible alternative would be
to have the client send a first request without the contents of
every modified file, then have the server tell it what files it
needs. Note the server needs to do the what-needs-to-be-updated
check twice (or more, if changes in the repository mean it has to
ask the client for more files), because it can't keep locks open
while waiting for the network. Perhaps this whole thing is
irrelevant if client-side repositories are implemented, and the
rcsmerge is done by the client.
File: cvsclient.info, Node: Connection and Authentication, Next: Protocol, Prev: Protocol Notes, Up: Top
How to Connect to and Authenticate Oneself to the CVS server
************************************************************
Connection and authentication occurs before the CVS protocol itself
is started. There are several ways to connect.
rsh
If the client has a way to execute commands on the server, and
provide input to the commands and output from them, then it can
connect that way. This could be the usual rsh (port 514)
protocol, Kerberos rsh, SSH, or any similar mechanism. The client
may allow the user to specify the name of the server program; the
default is `cvs'. It is invoked with one argument, `server'.
Once it invokes the server, the client proceeds to start the cvs
protocol.
kserver
The kerberized server listens on a port (in the current
implementation, by having inetd call "cvs kserver") which defaults
to 1999. The client connects, sends the usual kerberos
authentication information, and then starts the cvs protocol.
Note: port 1999 is officially registered for another use, and in
any event one cannot register more than one port for CVS, so the
kerberized client and server should be changed to use port 2401
(see below), and send a different string in place of `BEGIN AUTH
REQUEST' to identify the authentication method in use. However,
noone has yet gotten around to implementing this.
pserver
The password authenticated server listens on a port (in the current
implementation, by having inetd call "cvs pserver") which defaults
to 2401 (this port is officially registered). The client
connects, sends the string `BEGIN AUTH REQUEST', a linefeed, the
cvs root, a linefeed, the username, a linefeed, the password
trivially encoded (see scramble.c in the cvs sources), a linefeed,
the string `END AUTH REQUEST', and a linefeed. The server
responds with `I LOVE YOU' and a linefeed if the authentication is
successful or `I HATE YOU' and a linefeed if the authentication
fails. After receiving `I LOVE YOU', the client proceeds with the
cvs protocol. If the client wishes to merely authenticate without
starting the cvs protocol, the procedure is the same, except
`BEGIN AUTH REQUEST' is replaced with `BEGIN VERIFICATION
REQUEST', `END AUTH REQUEST' is replaced with `END VERIFICATION
REQUEST', and upon receipt of `I LOVE YOU' the connection is
closed rather than continuing.
File: cvsclient.info, Node: Protocol, Prev: Connection and Authentication, Up: Top
The CVS client/server protocol
******************************
In the following, `\n' refers to a linefeed and `\t' refers to a
horizontal tab.
* Menu:
* Entries Lines::
* Modes::
* Filenames:: Conventions regarding filenames
* Requests::
* Responses::
* Example::
* Requirements::
File: cvsclient.info, Node: Entries Lines, Next: Modes, Up: Protocol
Entries Lines
=============
Entries lines are transmitted as:
/ NAME / VERSION / CONFLICT / OPTIONS / TAG_OR_DATE
TAG_OR_DATE is either `T' TAG or `D' DATE or empty. If it is
followed by a slash, anything after the slash shall be silently ignored.
VERSION can be empty, or start with `0' or `-', for no user file,
new user file, or user file to be removed, respectively.
CONFLICT, if it starts with `+', indicates that the file had
conflicts in it. The rest of CONFLICT is `=' if the timestamp matches
the file, or anything else if it doesn't. If CONFLICT does not start
with a `+', it is silently ignored.
File: cvsclient.info, Node: Modes, Next: Filenames, Prev: Entries Lines, Up: Protocol
Modes
=====
A mode is any number of repetitions of
MODE-TYPE = DATA
separated by `,'.
MODE-TYPE is an identifier composed of alphanumeric characters.
Currently specified: `u' for user, `g' for group, `o' for other (see
below for discussion of whether these have their POSIX meaning or are
more loose). Unrecognized values of MODE-TYPE are silently ignored.
DATA consists of any data not containing `,', `\0' or `\n'. For
`u', `g', and `o' mode types, data consists of alphanumeric characters,
where `r' means read, `w' means write, `x' means execute, and
unrecognized letters are silently ignored.
The two most obvious ways in which the mode matters are: (1) is it
writeable? This is used by the developer communication features, and
is implemented even on OS/2 (and could be implemented on DOS), whose
notion of mode is limited to a readonly bit. (2) is it executable?
Unix CVS users need CVS to store this setting (for shell scripts and
the like). The current CVS implementation on unix does a little bit
more than just maintain these two settings, but it doesn't really have
a nice general facility to store or version control the mode, even on
unix, much less across operating systems with diverse protection
features. So all the ins and outs of what the mode means across
operating systems haven't really been worked out (e.g. should the VMS
port use ACLs to get POSIX semantics for groups?).
File: cvsclient.info, Node: Filenames, Next: Requests, Prev: Modes, Up: Protocol
Conventions regarding transmission of file names
================================================
In most contexts, `/' is used to separate directory and file names
in filenames, and any use of other conventions (for example, that the
user might type on the command line) is converted to that form. The
only exceptions might be a few cases in which the server provides a
magic cookie which the client then repeats verbatim, but as the server
has not yet been ported beyond unix, the two rules provide the same
answer (and what to do if future server ports are operating on a
repository like e:/foo or CVS_ROOT:[FOO.BAR] has not been carefully
thought out).
File: cvsclient.info, Node: Requests, Next: Responses, Prev: Filenames, Up: Protocol
Requests
========
File contents (noted below as FILE TRANSMISSION) can be sent in one
of two forms. The simpler form is a number of bytes, followed by a
newline, followed by the specified number of bytes of file contents.
These are the entire contents of the specified file. Second, if both
client and server support `gzip-file-contents', a `z' may precede the
length, and the `file contents' sent are actually compressed with
`gzip'. The length specified is that of the compressed version of the
file.
In neither case are the file content followed by any additional data.
The transmission of a file will end with a newline iff that file (or its
compressed form) ends with a newline.
`Root PATHNAME \n'
Response expected: no. Tell the server which `CVSROOT' to use.
PATHNAME must already exist; if creating a new root, use the
`init' request, not `Root'. PATHNAME does not include the
hostname of the server, how to access the server, etc.; by the time
the CVS protocol is in use, connection, authentication, etc., are
already taken care of.
`Valid-responses REQUEST-LIST \n'
Response expected: no. Tell the server what responses the client
will accept. request-list is a space separated list of tokens.
`valid-requests \n'
Response expected: yes. Ask the server to send back a
`Valid-requests' response.
`Repository REPOSITORY \n'
Response expected: no. Tell the server what repository to use.
This should be a directory name from a previous server response.
Note that this both gives a default for `Entry ' and `Modified '
and also for `ci' and the other commands; normal usage is to send a
`Repository ' for each directory in which there will be an `Entry
' or `Modified ', and then a final `Repository ' for the original
directory, then the command.
`Directory LOCAL-DIRECTORY \n'
Additional data: REPOSITORY \n. This is like `Repository', but
the local name of the directory may differ from the repository
name. If the client uses this request, it affects the way the
server returns pathnames; see *Note Responses::. LOCAL-DIRECTORY
is relative to the top level at which the command is occurring
(i.e. the last `Directory' or `Repository' which is sent before
the command).
`Max-dotdot LEVEL \n'
Tell the server that LEVEL levels of directories above the
directory which `Directory' requests are relative to will be
needed. For example, if the client is planning to use a
`Directory' request for `../../foo', it must send a `Max-dotdot'
request with a LEVEL of at least 2. `Max-dotdot' must be sent
before the first `Directory' request.
`Static-directory \n'
Response expected: no. Tell the server that the directory most
recently specified with `Repository' or `Directory' should not have
additional files checked out unless explicitly requested. The
client sends this if the `Entries.Static' flag is set, which is
controlled by the `Set-static-directory' and
`Clear-static-directory' responses.
`Sticky TAGSPEC \n'
Response expected: no. Tell the server that the directory most
recently specified with `Repository' has a sticky tag or date
TAGSPEC. The first character of TAGSPEC is `T' for a tag, or `D'
for a date. The remainder of TAGSPEC contains the actual tag or
date.
`Checkin-prog PROGRAM \n'
Response expected: no. Tell the server that the directory most
recently specified with `Directory' has a checkin program PROGRAM.
Such a program would have been previously set with the
`Set-checkin-prog' response.
`Update-prog PROGRAM \n'
Response expected: no. Tell the server that the directory most
recently specified with `Directory' has an update program PROGRAM.
Such a program would have been previously set with the
`Set-update-prog' response.
`Entry ENTRY-LINE \n'
Response expected: no. Tell the server what version of a file is
on the local machine. The name in ENTRY-LINE is a name relative
to the directory most recently specified with `Repository'. If
the user is operating on only some files in a directory, `Entry'
requests for only those files need be included. If an `Entry'
request is sent without `Modified', `Unchanged', or `Lost' for that
file the meaning depends on whether `UseUnchanged' has been sent;
if it has been it means the file is lost, if not it means the file
is unchanged.
`Modified FILENAME \n'
Response expected: no. Additional data: mode, \n, file
transmission. Send the server a copy of one locally modified
file. FILENAME is relative to the most recent repository sent
with `Repository'. If the user is operating on only some files in
a directory, only those files need to be included. This can also
be sent without `Entry', if there is no entry for the file.
`Lost FILENAME \n'
Response expected: no. Tell the server that FILENAME no longer
exists. The name is relative to the most recent repository sent
with `Repository'. This is used for any case in which `Entry' is
being sent but the file no longer exists. If the client has
issued the `UseUnchanged' request, then this request is not used.
`Unchanged FILENAME \n'
Response expected: no. Tell the server that FILENAME has not been
modified in the checked out directory. The name is relative to
the most recent repository sent with `Repository'. This request
can only be issued if `UseUnchanged' has been sent.
`UseUnchanged \n'
Response expected: no. Tell the server that the client will be
indicating unmodified files with `Unchanged', and that files for
which no information is sent are nonexistent on the client side,
not unchanged. This is necessary for correct behavior since only
the server knows what possible files may exist, and thus what
files are nonexistent.
`Notify FILENAME \n'
Tell the server that a `edit' or `unedit' command has taken place.
The server needs to send a `Notified' response, but such response
is deferred until the next time that the server is sending
responses. Response expected: no. Additional data:
NOTIFICATION-TYPE \t TIME \t CLIENTHOST \t
WORKING-DIR \t WATCHES \n
where NOTIFICATION-TYPE is `E' for edit or `U' for unedit, TIME is
the time at which the edit or unedit took place, CLIENTHOST is the
name of the host on which the edit or unedit took place, and
WORKING-DIR is the pathname of the working directory where the
edit or unedit took place. WATCHES are the temporary watches to
set; if it is followed by \t then the tab and the rest of the line
are ignored.
`Questionable FILENAME \n'
Response expected: no. Additional data: no. Tell the server to
check whether FILENAME should be ignored, and if not, next time the
server sends responses, send (in a `M' response) `?' followed by
the directory and filename.
`Case \n'
Tell the server that filenames should be matched against ignore
patterns in a case-insensitive fashion. Note that this does not
apply to other comparisons--for example the filenames given in
`Entry' and `Modified' requests for the same file must match in
case regardless of whether the `Case' request is sent.
`Argument TEXT \n'
Response expected: no. Save argument for use in a subsequent
command. Arguments accumulate until an argument-using command is
given, at which point they are forgotten.
`Argumentx TEXT \n'
Response expected: no. Append \n followed by text to the current
argument being saved.
`Global_option OPTION \n'
Transmit one of the global options `-q', `-Q', `-l', `-t', `-r',
or `-n'. OPTION must be one of those strings, no variations (such
as combining of options) are allowed. For graceful handling of
`valid-requests', it is probably better to make new global options
separate requests, rather than trying to add them to this request.
`Set VARIABLE=VALUE \n'
Set a user variable VARIABLE to VALUE.
`expand-modules \n'
Response expected: yes. Expand the modules which are specified in
the arguments. Returns the data in `Module-expansion' responses.
Note that the server can assume that this is checkout or export,
not rtag or rdiff; the latter do not access the working directory
and thus have no need to expand modules on the client side.
`co \n'
`ci \n'
`diff \n'
`tag \n'
`status \n'
`log \n'
`add \n'
`remove \n'
`rdiff \n'
`rtag \n'
`admin \n'
`export \n'
`history \n'
`watchers \n'
`editors \n'
`annotate \n'
Response expected: yes. Actually do a cvs command. This uses any
previous `Argument', `Repository', `Entry', `Modified', or `Lost'
requests, if they have been sent. The last `Repository' sent
specifies the working directory at the time of the operation. No
provision is made for any input from the user. This means that
`ci' must use a `-m' argument if it wants to specify a log message.
`init ROOT-NAME \n'
Response expected: yes. If it doesn't already exist, create a CVS
repository ROOT-NAME. The `Root' request need not have been
previously sent.
`update \n'
Response expected: yes. Actually do a `cvs update' command. This
uses any previous `Argument', `Repository', `Entry', `Modified',
or `Lost' requests, if they have been sent. The last `Repository'
sent specifies the working directory at the time of the operation.
The `-I' option is not used-files which the client can decide
whether to ignore are not mentioned and the client sends the
`Questionable' request for others.
`import \n'
Response expected: yes. Actually do a `cvs import' command. This
uses any previous `Argument', `Repository', `Entry', `Modified',
or `Lost' requests, if they have been sent. The last `Repository'
sent specifies the working directory at the time of the operation.
The files to be imported are sent in `Modified' requests (files
which the client knows should be ignored are not sent; the server
must still process the CVSROOT/cvsignore file unless -I ! is
sent). A log message must have been specified with a `-m'
argument.
`watch-on \n'
`watch-off \n'
`watch-add \n'
`watch-remove \n'
Response expected: yes. Actually do the `cvs watch on', `cvs
watch off', `cvs watch add', and `cvs watch remove' commands,
respectively. This uses any previous `Argument', `Repository',
`Entry', `Modified', or `Lost' requests, if they have been sent.
The last `Repository' sent specifies the working directory at the
time of the operation.
`release \n'
Response expected: yes. Note that a `cvs release' command has
taken place and update the history file accordingly.
`noop \n'
Response expected: yes. This request is a null command in the
sense that it doesn't do anything, but merely (as with any other
requests expecting a response) sends back any responses pertaining
to pending errors, pending `Notified' responses, etc.
`update-patches \n'
This request does not actually do anything. It is used as a
signal that the server is able to generate patches when given an
`update' request. The client must issue the `-u' argument to
`update' in order to receive patches.
`gzip-file-contents LEVEL \n'
This request asks the server to filter files it sends to the client
through the `gzip' program, using the specified level of
compression. If this request is not made, the server must not do
any compression.
This is only a hint to the server. It may still decide (for
example, in the case of very small files, or files that already
appear to be compressed) not to do the compression. Compression
is indicated by a `z' preceding the file length.
Availability of this request in the server indicates to the client
that it may compress files sent to the server, regardless of
whether the client actually uses this request.
`OTHER-REQUEST TEXT \n'
Response expected: yes. Any unrecognized request expects a
response, and does not contain any additional data. The response
will normally be something like `error unrecognized request', but
it could be a different error if a previous command which doesn't
expect a response produced an error.
When the client is done, it drops the connection.
File: cvsclient.info, Node: Responses, Next: Example, Prev: Requests, Up: Protocol
Responses
=========
After a command which expects a response, the server sends however
many of the following responses are appropriate. Pathnames are of the
actual files operated on (i.e. they do not contain `,v' endings), and
are suitable for use in a subsequent `Repository' request. However, if
the client has used the `Directory' request, then it is instead a local
directory name relative to the directory in which the command was given
(i.e. the last `Directory' before the command). Then a newline and a
repository name (the pathname which is sent if `Directory' is not
used). Then the slash and the filename. For example, for a file
`i386.mh' which is in the local directory `gas.clean/config' and for
which the repository is `/rel/cvsfiles/devo/gas/config':
gas.clean/config/
/rel/cvsfiles/devo/gas/config/i386.mh
Any response always ends with `error' or `ok'. This indicates that
the response is over.
`Valid-requests REQUEST-LIST \n'
Indicate what requests the server will accept. REQUEST-LIST is a
space separated list of tokens. If the server supports sending
patches, it will include `update-patches' in this list. The
`update-patches' request does not actually do anything.
`Checked-in PATHNAME \n'
Additional data: New Entries line, \n. This means a file PATHNAME
has been successfully operated on (checked in, added, etc.). name
in the Entries line is the same as the last component of PATHNAME.
`New-entry PATHNAME \n'
Additional data: New Entries line, \n. Like `Checked-in', but the
file is not up to date.
`Updated PATHNAME \n'
Additional data: New Entries line, \n, mode, \n, file
transmission. A new copy of the file is enclosed. This is used
for a new revision of an existing file, or for a new file, or for
any other case in which the local (client-side) copy of the file
needs to be updated, and after being updated it will be up to
date. If any directory in pathname does not exist, create it.
`Merged PATHNAME \n'
This is just like `Updated' and takes the same additional data,
with the one difference that after the new copy of the file is
enclosed, it will still not be up to date. Used for the results
of a merge, with or without conflicts.
`Patched PATHNAME \n'
This is just like `Updated' and takes the same additional data,
with the one difference that instead of sending a new copy of the
file, the server sends a patch produced by `diff -u'. This client
must apply this patch, using the `patch' program, to the existing
file. This will only be used when the client has an exact copy of
an earlier revision of a file. This response is only used if the
`update' command is given the `-u' argument.
`Mode MODE \n'
This MODE applies to the next file mentioned in `Checked-in'. It
does not apply to any request which follows a `Checked-in',
`New-entry', `Updated', `Merged', or `Patched' response.
`Checksum CHECKSUM\n'
The CHECKSUM applies to the next file sent over via `Updated',
`Merged', or `Patched'. In the case of `Patched', the checksum
applies to the file after being patched, not to the patch itself.
The client should compute the checksum itself, after receiving the
file or patch, and signal an error if the checksums do not match.
The checksum is the 128 bit MD5 checksum represented as 32 hex
digits. This response is optional, and is only used if the client
supports it (as judged by the `Valid-responses' request).
`Copy-file PATHNAME \n'
Additional data: NEWNAME \n. Copy file PATHNAME to NEWNAME in the
same directory where it already is. This does not affect
`CVS/Entries'.
`Removed PATHNAME \n'
The file has been removed from the repository (this is the case
where cvs prints `file foobar.c is no longer pertinent').
`Remove-entry PATHNAME \n'
The file needs its entry removed from `CVS/Entries', but the file
itself is already gone (this happens in response to a `ci' request
which involves committing the removal of a file).
`Set-static-directory PATHNAME \n'
This instructs the client to set the `Entries.Static' flag, which
it should then send back to the server in a `Static-directory'
request whenever the directory is operated on. PATHNAME ends in a
slash; its purpose is to specify a directory, not a file within a
directory.
`Clear-static-directory PATHNAME \n'
Like `Set-static-directory', but clear, not set, the flag.
`Set-sticky PATHNAME \n'
Additional data: TAGSPEC \n. Tell the client to set a sticky tag
or date, which should be supplied with the `Sticky' request for
future operations. PATHNAME ends in a slash; its purpose is to
specify a directory, not a file within a directory. The first
character of TAGSPEC is `T' for a tag, or `D' for a date. The
remainder of TAGSPEC contains the actual tag or date.
`Clear-sticky PATHNAME \n'
Clear any sticky tag or date set by `Set-sticky'.
`Template PATHNAME \n'
Additional data: file transmission (note: compressed file
transmissions are not supported). PATHNAME ends in a slash; its
purpose is to specify a directory, not a file within a directory.
Tell the client to store the file transmission as the template log
message, and then use that template in the future when prompting
the user for a log message.
`Set-checkin-prog DIR \n'
Additional data: PROG \n. Tell the client to set a checkin
program, which should be supplied with the `Checkin-prog' request
for future operations.
`Set-update-prog DIR \n'
Additional data: PROG \n. Tell the client to set an update
program, which should be supplied with the `Update-prog' request
for future operations.
`Notified PATHNAME \n'
Indicate to the client that the notification for PATHNAME has been
done. There should be one such response for every `Notify'
request; if there are several `Notify' requests for a single file,
the requests should be processed in order; the first `Notified'
response pertains to the first `Notify' request, etc.
`Module-expansion PATHNAME \n Return a file or directory'
which is included in a particular module. PATHNAME is relative to
cvsroot, unlike most pathnames in responses. PATHNAME should be
used to look and see whether some or all of the module exists on
the client side; it is not necessarily suitable for passing as an
argument to a `co' request (for example, if the modules file
contains the `-d' option, it will be the directory specified with
`-d', not the name of the module).
`M TEXT \n'
A one-line message for the user.
`E TEXT \n'
Same as `M' but send to stderr not stdout.
`error ERRNO-CODE ` ' TEXT \n'
The command completed with an error. ERRNO-CODE is a symbolic
error code (e.g. `ENOENT'); if the server doesn't support this
feature, or if it's not appropriate for this particular message,
it just omits the errno-code (in that case there are two spaces
after `error'). Text is an error message such as that provided by
strerror(), or any other message the server wants to use.
`ok \n'
The command completed successfully.
File: cvsclient.info, Node: Example, Next: Requirements, Prev: Responses, Up: Protocol
Example
=======
Lines beginning with `c>' are sent by the client; lines beginning
with `s>' are sent by the server; lines beginning with `#' are not part
of the actual exchange.
c> Root /rel/cvsfiles
# In actual practice the lists of valid responses and requests would
# be longer
c> Valid-responses Updated Checked-in M ok error
c> valid-requests
s> Valid-requests Root co Modified Entry Repository ci Argument Argumentx
s> ok
# cvs co devo/foo
c> Argument devo/foo
c> co
s> Updated /rel/cvsfiles/devo/foo/foo.c
s> /foo.c/1.4/Mon Apr 19 15:36:47 1993 Mon Apr 19 15:36:47 1993//
s> 26
s> int mein () { abort (); }
s> Updated /rel/cvsfiles/devo/foo/Makefile
s> /Makefile/1.2/Mon Apr 19 15:36:47 1993 Mon Apr 19 15:36:47 1993//
s> 28
s> foo: foo.c
s> $(CC) -o foo $<
s> ok
# In actual practice the next part would be a separate connection.
# Here it is shown as part of the same one.
c> Repository /rel/cvsfiles/devo/foo
# foo.c relative to devo/foo just set as Repository.
c> Entry /foo.c/1.4/Mon Apr 19 15:36:47 1993 Mon Apr 19 15:36:47 1993//
c> Entry /Makefile/1.2/Mon Apr 19 15:36:47 1993 Mon Apr 19 15:36:47 1993//
c> Modified foo.c
c> 26
c> int main () { abort (); }
# cvs ci -m <log message> foo.c
c> Argument -m
c> Argument Well, you see, it took me hours and hours to find this typo and I
c> Argumentx searched and searched and eventually had to ask John for help.
c> Argument foo.c
c> ci
s> Checked-in /rel/cvsfiles/devo/foo/foo.c
s> /foo.c/1.5/ Mon Apr 19 15:54:22 CDT 1993//
s> M Checking in foo.c;
s> M /cygint/rel/cvsfiles/devo/foo/foo.c,v <-- foo.c
s> M new revision: 1.5; previous revision: 1.4
s> M done
s> ok
File: cvsclient.info, Node: Requirements, Prev: Example, Up: Protocol
Required versus optional parts of the protocol
==============================================
The following are part of every known implementation of the CVS
protocol and it is considered reasonable behavior to completely fail to
work if you are connected with an implementation which attempts to not
support them. Requests: Root, Valid-responses, valid-requests,
Repository, Entry, Modified, Argument, Argumentx, ci, co, update.
Responses: ok, error, Valid-requests, Checked-in, Updated, Merged,
Removed, M, E.
Failure to support the Directory, UseUnchanged, and Unchanged
requests is deprecated. CVS 1.5 and later have supported these
requests and in the future it will be considered reasonable behavior to
completely fail to work with an implementation which attempts to not
support them. Support for the Repository and Lost requests is
deprecated; CVS clients 1.5 and later will not use them if
communicating with a server which supports Directory and UseUnchanged.
Tag Table:
Node: Top99
Node: Introduction924
Node: Goals3458
Node: Notes4964
Node: Protocol Notes6208
Node: Connection and Authentication7911
Node: Protocol10514
Node: Entries Lines10913
Node: Modes11621
Node: Filenames13144
Node: Requests13895
Node: Responses26668
Node: Example34133
Node: Requirements36079
End Tag Table
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