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Clean up recent VC updates.

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Richard M. Stallman 2001-02-25 17:24:19 +00:00
parent 12f1370484
commit 7d5e745e86
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@ -1061,9 +1061,8 @@ file just once. Version control systems also record history information
such as the creation time of each version, who created it, and a
description of what was changed in that version.
The Emacs version control interface is called VC. It allows you to
use various version control systems from within
Emacs---currently, it supports RCS, CVS, and SCCS. The GNU
The Emacs version control interface is called VC. Its commands work
with three version control systems---RCS, CVS, and SCCS. The GNU
project recommends RCS and CVS, which are free software and available
from the Free Software Foundation. We also have free software to
replace SCCS, known as CSSC; if you are using SCCS and don't want to
@ -1226,7 +1225,7 @@ RCS normally use locking; CVS normally does not use locking.
@menu
* VC with Locking:: RCS in its default mode, SCCS, and optionally CVS.
* Without Locking:: Without locking: default mode for CVS.
* Extended Actions:: Avanced features available with a prefix argument.
* Extended C-x C-q:: Advanced features available with a prefix argument.
* Log Buffer:: Features available in log entry buffers.
@end menu
@ -1274,11 +1273,11 @@ work file.
@itemize @bullet
@item
If some other user has checked in changes into the master file,
Emacs asks you whether you want to merge those changes into your own
work file. You must do this before you can check in
your own changes. (To pick up any recent changes from the master file
@emph{without} trying to commit your own changes, type @kbd{C-x v m RET}.)
If some other user has checked in changes into the master file, Emacs
asks you whether you want to merge those changes into your own work
file. You must do this before you can check in your own changes. (To
pick up any recent changes from the master file @emph{without} trying
to commit your own changes, type @kbd{C-x v m @key{RET}}.)
@xref{Merging}.
@item
@ -1306,29 +1305,33 @@ with RCS in a future Emacs version.
it is not required; @kbd{C-x C-q} with an unmodified file locks the
file, just as it does with RCS in its normal (locking) mode.
@node Extended Actions
@subsubsection Calling @code{vc-next-action} with a Prefix Argument
@node Advanced C-x C-q
@subsubsection Advanced Control in @kbd{C-x C-q}
When you give a prefix argument to @code{vc-next-action} (@kbd{C-u C-x
C-q}), it still performs the next logical version control operation, but
in an extended sense.
When you give a prefix argument to @code{vc-next-action} (@kbd{C-u
C-x C-q}), it still performs the next logical version control
operation, but accepts additional arguments to specify precisely how
to do the operation.
@itemize @bullet
@item If the file is modified (or locked), you can specify the version
number that should be used for check-in. This is also one way to create
a new branch (@pxref{Branches}).
@item
If the file is modified (or locked), you can specify the version
number to use for the new verion that you check-in. This is one way
to create a new branch (@pxref{Branches}).
@item If the file is not modified (and unlocked), you can specify a new
version to go to; this lets you start working from an older version, or
on another branch. If you do not enter any version, that takes you to
the highest version on the current branch; therefore @kbd{C-u C-x C-q
RET} is a convenient way to get the latest version of a file from the
repository.
@item
If the file is not modified (and unlocked), you can specify the
version to select; this lets you start working from an older version,
or on another branch. If you do not enter any version, that takes you
to the highest version on the current branch; therefore @kbd{C-u C-x
C-q @key{RET}} is a convenient way to get the latest version of a file from
the repository.
@item Regardless of the state of the file, you can also enter the name
of another version control system instead of a version number. This
lets you use more than one version control system for a file
(@pxref{Local Version Control}).
@item
Instead of the version number, you can also specify the name of a
version control system. This is useful when one file is being managed
with two version control systems at the same time file (@pxref{Local
Version Control}).
@end itemize
@node Log Buffer
@ -1393,33 +1396,33 @@ and create a branch from it. @xref{Branches}.)
It is usually more convenient to compare two versions of the file,
with the command @kbd{C-x v =} (@code{vc-diff}). Plain @kbd{C-x v =}
compares the current buffer contents (saving them in the file if
necessary) with the last checked-in version of the file. @kbd{C-u C-x v
=}, with a numeric argument, reads a file name and two version numbers,
then compares those versions of the specified file.
If you supply a directory name instead of the name of a registered
file, this command compares the two specified versions of all registered
files in that directory and its subdirectories.
necessary) with the last checked-in version of the file. @kbd{C-u C-x
v =}, with a numeric argument, reads a file name and two version
numbers, then compares those versions of the specified file. Both
forms display the output in a special buffer in another window.
You can specify a checked-in version by its number; an empty input
specifies the current contents of the work file (which may be different
from all the checked-in versions). You can also specify a snapshot name
(@pxref{Snapshots}) instead of one or both version numbers.
If you supply a directory name instead of the name of a registered
file, this command compares the two specified versions of all registered
files in that directory and its subdirectories.
@vindex diff-switches
@vindex vc-diff-switches
This command works by running a variant of the @code{diff} utility
that is specific to the version control system in use. Emacs passes the
contents of the variable @code{diff-switches} to that utility; you can
define specific options for version control in @code{vc-diff-switches},
and there are similar variables for each specific system,
e.g. @code{vc-rcs-diff-switches}, and the like.
@kbd{C-x v =} works by running a variant of the @code{diff} utility
designed to work with the version control system in use. Emacs passes
the contents of the variable @code{diff-switches} to it; you can
specify comparison options for version control in
@code{vc-diff-switches}, and there are similar variables for each
specific system---@code{vc-rcs-diff-switches}, and so on.
The output of the @code{diff} command is displayed in a special buffer
in another window. Unlike the @kbd{M-x diff} command, @kbd{C-x v =}
does not try to locate the changes in the old and new versions. This is
because normally one or both versions do not exist as files when you
compare them; they exist only in the records of the master file.
Unlike the @kbd{M-x diff} command, @kbd{C-x v =} does not try to
locate the changes in the old and new versions. This is because
normally one or both versions do not exist as files when you compare
them; they exist only in the records of the master file.
@xref{Comparing Files}, for more information about @kbd{M-x diff}.
@findex vc-annotate
@ -1469,9 +1472,8 @@ register the file---for example, you cannot register a file under CVS if
its directory is not already part of a CVS tree.
With the default value of @var{vc-handled-backends}, this means that
Emacs uses RCS if there are any files under RCS control, and CVS if
there are any files under CVS. If there are no files under version
control, RCS is used.
Emacs uses RCS if there are any files under RCS control, or CVS if
there are any files under CVS, or RCS as the ultimate default.
If locking is in use, @kbd{C-x v i} leaves the file unlocked and
read-only. Type @kbd{C-x C-q} if you wish to start editing it. After
@ -1722,7 +1724,7 @@ locked.
You can omit the minor version number, thus giving only the branch
number; this takes you to the head version on the chosen branch. If you
only type @kbd{RET}, Emacs goes to the highest version on the trunk.
only type @key{RET}, Emacs goes to the highest version on the trunk.
After you have switched to any branch (including the main branch), you
stay on it for subsequent VC commands, until you explicitly select some
@ -1781,7 +1783,7 @@ Merge changes into the work file.
@kbd{C-x v m} (@code{vc-merge}) takes a set of changes and merges it
into the current version of the work file. It firsts asks you in the
minibuffer where the changes should come from. If you just type
@kbd{RET}, Emacs merges any changes that were made on the same branch
@key{RET}, Emacs merges any changes that were made on the same branch
since you checked the file out (we call this @dfn{merging the news}).
This is the common way to pick up recent changes from the repository,
regardless of whether you have already changed the file yourself.
@ -1795,9 +1797,9 @@ of the current file.
branch 1.3.1. In the meantime, development on the trunk has proceeded
to version 1.5. To merge the changes from the branch to the trunk,
first go to the head version of the trunk, by typing @kbd{C-u C-x C-q
RET}. Version 1.5 is now current. If locking is used for the file,
@key{RET}}. Version 1.5 is now current. If locking is used for the file,
type @kbd{C-x C-q} to lock version 1.5 so that you can change it. Next,
type @kbd{C-x v m 1.3.1 RET}. This takes the entire set of changes on
type @kbd{C-x v m 1.3.1 @key{RET}}. This takes the entire set of changes on
branch 1.3.1 (relative to version 1.3, where the branch started, up to
the last version on the branch) and merges it into the current version
of the work file. You can now check in the changed file, thus creating
@ -1867,16 +1869,15 @@ during this particular editing session.
@subsection Remote Repositories
@cindex remote repositories (CVS)
Many projects set up a central CVS repository somewhere in the Internet,
and let each user check out a personal working copy of the files to
his local machine. Committing changes to the repository, and picking
up changes from other users into one's own working area, then works by
direct interactions with the CVS server.
A common way of using CVS is to set up a central CVS repository on
some Internet host, then have each developer check out a personal
working copy of the files on his local machine. Committing changes to
the repository, and picking up changes from other users into one's own
working area, then works by direct interactions with the CVS server.
The problem is that access to the CVS server is often slow, and that
developers might need to work offline as well. VC therefore offers
some features that allow you to keep network interactions to a
minimum.
One difficulty is that access to the CVS server is often slow, and
that developers might need to work offline as well. VC is designed
to reduce the amount of network interaction necessary.
@menu
* Version Backups:: Keeping local copies of repository versions.
@ -1887,45 +1888,50 @@ minimum.
@subsubsection Version Backups
@cindex version backups
When VC sees that the CVS repository for a file is on a remote machine,
it automatically makes local backups of unmodified versions of the file.
This means that you can compare the file to the repository version
(@kbd{C-x v =}), or revert to that version (@kbd{C-x v u}), without any
network interactions.
The local copy of the unmodified file is called a @dfn{version backup}.
This is to indicate that it corresponds exactly to a version that is
stored in the repository. Note that version backups are related to,
but distinct from the other kinds of backups that Emacs can make:
single backups and numbered backups (@pxref{Backup}).
@vindex vc-cvs-stay-local
For a file that comes from a remote CVS repository, VC makes a version
backup whenever you save the first changes to the file, and removes it
after you have committed your modified version to the repository. (You
can switch this off by setting the variable @code{vc-cvs-stay-local} to
@code{nil}.)
@cindex automatic version backups
@cindex manual version backups
The name of a version backup for a file named @var{file}, with version
@var{version}, is @code{@var{file}.~@var{version}.~}. Note that this
naming convention is almost the same as that used by @kbd{C-x v ~}
(@pxref{Old Versions}), the only difference being the additional dot
(@samp{.}) after the version number. This similarity is intentional,
because both kinds of files store the same kind of information. To
distinguish between them, we speak of @dfn{automatic version backups}
(those created by the mechanism described here) and @dfn{manual version
backups} (created by @kbd{C-x v ~}). Their primary difference is that
Emacs deletes automatic version backups when you commit to the
repository (this is why the trailing dot is needed to identify them),
while manual version backups are never deleted automatically.
When VC sees that the CVS repository for a file is on a remote
machine, it automatically makes local backups of unmodified versions
of the file---@dfn{automatic version backups}. This means that you
can compare the file to the repository version (@kbd{C-x v =}), or
revert to that version (@kbd{C-x v u}), without any network
interactions.
Each of the two mechanisms can use the files created by the other one.
For example, if you changed a file outside of Emacs, so that no
automatic version backup was created, you can create a manual backup of
that version using @kbd{C-x v ~}. Emacs will then use that file for
local diff and revert operations.
The local copy of the unmodified file is called a @dfn{version
backup} to indicate that it corresponds exactly to a version that is
stored in the repository. Note that version backups are not the same
as ordinary Emacs backup files (@pxref{Backup}). But they follow a
similar naming convention.
For a file that comes from a remote CVS repository, VC makes a
version backup whenever you save the first changes to the file, and
removes it after you have committed your modified version to the
repository. You can disable the making of automatic version backups by
setting @code{vc-cvs-stay-local} to @code{nil} (@pxref{CVS Options}).
@cindex manual version backups
The name of the automatic version backup for version @var{version}
of file @var{file} is @code{@var{file}.~@var{version}.~}. This is
almost the same as the name used by @kbd{C-x v ~} (@pxref{Old
Versions}), the only difference being the additional dot (@samp{.})
after the version number. This similarity is intentional, because
both kinds of files store the same kind of information. The file made
by @kbd{C-x v ~} acts as a @dfn{manual version backup}.
All the VC commands that operate on old versions of a file can use
both kinds of version backups. For instance, @kbd{C-x v ~} uses
either an automatic or a manual version backup, if possible, to get
the contents of the version you request. Likewise, @kbd{C-x v =} and
@kbd{C-x v u} use either an automatic or a manual version backup, if
one of them exists, to get the contents of a version to compare or
revert to. If you changed a file outside of Emacs, so that no
automatic version backup was created for the previous text, you can
create a manual backup of that version using @kbd{C-x v ~}, and thus
obtain the benefit of the local copy for Emacs commands.
The only difference in Emacs's handling of manual and automatic
version backups, once they exist, is that Emacs deletes automatic
version backups when you commit to the repository. By contrast,
manual version backups remain until you delete them.
@node Local Version Control
@subsubsection Local Version Control
@ -1945,27 +1951,26 @@ that the remote system is CVS, and you use RCS locally, although the
mechanism works with any combination of version control systems
(@dfn{back ends}).
To make it work with other back ends, you must make sure that the "more
local" back end comes before the "more remote" back end in the setting
of @var{vc-handled-backends} (@pxref{Customizing VC}). By default, this
variable is set up correctly so that you can use RCS and CVS as
described here.
To make it work with other back ends, you must make sure that the
``more local'' back end comes before the ``more remote'' back end in
the setting of @var{vc-handled-backends} (@pxref{Customizing VC}). By
default, this variable is set up so that you can use remote CVS and
local RCS as described here.
To start using local RCS for a file that comes from a remote CVS server,
you must @dfn{commit the file to RCS}, by typing @kbd{C-u C-x v v rcs
RET}. (In other words, @code{vc-next-action}, when called with a prefix
argument, accepts a back end name in place of the version to commit to.)
VC then registers the file under RCS.
To start using local RCS for a file that comes from a remote CVS
server, you must @emph{register the file in RCS}, by typing @kbd{C-u
C-x v v rcs @key{RET}}. (In other words, use @code{vc-next-action} with a
prefix argument, and specify RCS as the back end.)
You can commit to RCS at any time; it does not matter whether you have
You can do this at any time; it does not matter whether you have
already modified the file with respect to the version in the CVS
repository. If possible, VC tries to make the RCS master start with
the unmodified repository version, then checking in any local changes
as a new version. This works if you have not made any changes yet,
or if the unmodified repository version exists locally as a version
as a new version. This works if you have not made any changes yet, or
if the unmodified repository version exists locally as a version
backup (@pxref{Version Backups}). If the unmodified version is not
available locally, the RCS master starts with the modified version;
the only problem with this is that you cannot compare your changes
the only drawback of this is that you cannot compare your changes
locally to what is stored in the repository.
The version number of the RCS master is derived from the current CVS
@ -1973,55 +1978,61 @@ version, starting a branch from it. For example, if the current CVS
version is 1.23, the local RCS branch will be 1.23.1. Version 1.23 in
the RCS master will be identical to version 1.23 under CVS; your first
changes are checked in as 1.23.1.1. (If the unmodified file is not
available locally, VC will check-in the modified file twice, both as
available locally, VC will check in the modified file twice, both as
1.23 and 1.23.1.1, to make the revision numbers consistent.)
If you do not use locking under CVS (the default), locking is also
switched off under RCS, so that editing under RCS works exactly as
under CVS.
disabled for RCS, so that editing under RCS works exactly as under
CVS.
When you are done with your edits, you can commit the final version back
to the CVS repository, typing @kbd{C-u C-x v v cvs RET}. Emacs will
initialize the log entry buffer (@pxref{Log Buffer}) to contain all the
check-in comments you have made in the RCS master; you can make changes
to these comments as needed and then commit to CVS by typing @kbd{C-c
C-c}. If the commit is successful, VC finally removes the RCS master,
so that the file becomes once again registered under CVS only. (The RCS
master is not actually deleted, but renamed by adding a @samp{~} to its
name, so that you can get back to it later if you want.)
When you are done with your edits, you can commit the final version
back to the CVS repository, typing @kbd{C-u C-x v v cvs @key{RET}}. Emacs
will initialize the log entry buffer (@pxref{Log Buffer}) to contain
all the log entries you have recorded in the RCS master; you can make
changes to these comments as needed, and then commit in CVS by typing
@kbd{C-c C-c}. If the commit is successful, VC removes the RCS
master, so that the file is once again registered under CVS only.
(The RCS master is not actually deleted, just renamed by appending
@samp{~} to the name, so that you can refer to it later if you wish.)
While you are working with a local RCS master, you might still want to
While you are working with a local RCS master, you may still want to
pick up recent changes from the CVS repository into your local file,
or you might want to commit some of your changes back to CVS, without
actually switching back to CVS completely. VC lets you do this by
actually switching back to CVS completely. You can do this by
switching to another backend temporarily.
@table @kbd
@item C-x v b
Switch to any other back end that the current file is registered
Switch to another back end that the current file is registered
under (@code{vc-switch-backend}).
@item C-u C-x v b @var{backend} @key{RET}
Switch to @var{backend} for the current file.
@end table
@kindex C-x v b
@findex vc-switch-backend
@kbd{C-x v b} does not change the buffer contents, or any files; it
only changes VC's perspective on how to handle the file. Any
subsequent VC commands for that file will operate on the back end that
is currently selected.
If the current file is registered in more than one back end, typing
@kbd{C-x v b} lets you ``cycle'' through these back ends. (With a prefix
argument, it asks for the back end to use in the minibuffer.) This
command does not change any files, it only changes VC's perspective of
the file. Any other VC commands that you use on a file will operate on
the back end that is currently selected.
@kbd{C-x v b} ``cycles'' through all of these back ends. With a
prefix argument, it asks for the back end to use in the minibuffer.
Thus, if you have a file under local RCS, and you want to pick up some
recent changes from CVS, type @kbd{C-x v b} to switch to CVS, and then
@kbd{C-x v m RET} to merge the news (@pxref{Merging}). You can then switch
back to RCS by typing @kbd{C-x v b} again, and continue to edit locally.
@kbd{C-x v m @key{RET}} to merge the news (@pxref{Merging}). You can
then switch back to RCS by typing @kbd{C-x v b} again, and continue to
edit locally.
Note though, that if you do this, the revision numbers in the RCS
master no longer correspond to those of CVS in a meaningful way.
Technically, this is not a problem, but it might be more difficult for
you to keep track of what is in the repository and what is not. So we
suggest that, frequently, you commit your changes back to CVS
completely using @kbd{C-u C-x v v cvs RET}.
completely using @kbd{C-u C-x v v cvs @key{RET}}.
@node Snapshots
@subsection Snapshots
@ -2172,9 +2183,8 @@ messages that start with `#'.}. Then @kbd{C-x v a} visits
@noindent
You can then edit the new change log entry further as you wish.
Unfortunately, timestamps in ChangeLog files are only dates, so some
of the new change log entry may duplicate what's already in ChangeLog.
You will have to remove these duplicates by hand.
Some of the new change log entry may duplicate what's already in
ChangeLog. You will have to remove these duplicates by hand.
Normally, the log entry for file @file{foo} is displayed as @samp{*
foo: @var{text of log entry}}. The @samp{:} after @file{foo} is omitted
@ -2391,10 +2401,9 @@ default. The order is also significant when you register a file for
the first time, @pxref{Registering} for details.
@menu
* General VC Options:: Options not specific for any back end system.
* RCS Options:: Options for RCS.
* General VC Options:: Options that apply to multiple back ends.
* RCS and SCCS:: Options for RCS and SCCS.
* CVS Options:: Options for CVS.
* SCCS Options:: Options for SCCS.
@end menu
@node General VC Options
@ -2443,12 +2452,13 @@ additional messages when the commands finish.
@vindex vc-path
You can specify additional directories to search for version control
programs by setting the variable @code{vc-path}. These directories are
searched before the usual search path. But the proper files are usually
found automatically.
programs by setting the variable @code{vc-path}. These directories
are searched before the usual search path. It is rarely necessary to
set this variable, because VC normally finds the proper files
automatically.
@node RCS Options
@subsubsection Options specific for RCS
@node RCS and SCCS
@subsubsection Options for RCS and SCCS
@cindex non-strict locking (RCS)
@cindex locking, non-strict (RCS)
@ -2456,10 +2466,10 @@ found automatically.
users, but there is a mode called @dfn{non-strict locking} in which
you can check-in changes without locking the file first. Use
@samp{rcs -U} to switch to non-strict locking for a particular file,
see the @samp{rcs(1)} manpage for details.
see the @code{rcs} manpage for details.
When deducing the version control state of a file, VC first looks
for an RCS version header string in the file (@pxref{Version
When deducing the version control state of an RCS file, VC first
looks for an RCS version header string in the file (@pxref{Version
Headers}). If there is no header string, VC normally looks at the
file permissions of the work file; this is fast. But there might be
situations when the file permissions cannot be trusted. In this case
@ -2471,8 +2481,8 @@ version.
@vindex vc-consult-headers
You can tell VC not to use version headers to determine the file
status by setting @code{vc-consult-headers} to @code{nil}. VC then
always uses the file permissions (if it can trust them), or else
checks the master file.
always uses the file permissions (if it is supposed to trust them), or
else checks the master file.
@vindex vc-mistrust-permissions
You can specify the criterion for whether to trust the file
@ -2486,6 +2496,11 @@ permissions. If you find that the file permissions of work files are
changed erroneously, set @code{vc-mistrust-permissions} to @code{t}.
Then VC always checks the master file to determine the file's status.
VC determines the version control state of files under SCCS much as
with RCS. It does not consider SCCS version headers, though. Thus,
the variable @var{vc-mistrust-permissions} affects SCCS use, but
@var{vc-consult-headers} does not.
@node CVS Options
@subsubsection Options specific for CVS
@ -2496,14 +2511,15 @@ there are ways to restrict this, resulting in behavior that resembles
locking.
@cindex CVSREAD environment variable (CVS)
For one thing, you can set the @env{CVSREAD} environment variable to
an arbitrary value. If this variable is defined, CVS makes your work
files read-only by default. In Emacs, you must type @kbd{C-x C-q} to
make the file writeable, so that editing works in fact similar as if
locking was used. Note however, that no actual locking is performed, so
several users can make their files writeable at the same time. When
setting @env{CVSREAD} for the first time, make sure to check out all
your modules anew, so that the file protections are set correctly.
For one thing, you can set the @env{CVSREAD} environment variable
(the value you use makes no difference). If this variable is defined,
CVS makes your work files read-only by default. In Emacs, you must
type @kbd{C-x C-q} to make the file writeable, so that editing works
in fact similar as if locking was used. Note however, that no actual
locking is performed, so several users can make their files writeable
at the same time. When setting @env{CVSREAD} for the first time, make
sure to check out all your modules anew, so that the file protections
are set correctly.
@cindex cvs watch feature
@cindex watching files (CVS)
@ -2526,7 +2542,7 @@ consequence of this is that when you have modified a file, and somebody
else has already checked in other changes to the file, you are not
notified of it until you actually try to commit. (But you can try to
pick up any recent changes from the repository first, using @kbd{C-x v m
RET}, @pxref{Merging}).
@key{RET}}, @pxref{Merging}).
When @var{vc-cvs-stay-local} is @code{t}, VC also makes local
version backups, so that simple diff and revert operations are
@ -2537,18 +2553,9 @@ then VC queries the remote repository @emph{before} it decides what to
do in @code{vc-next-action} (@kbd{C-x v v}), just as it does for local
repositories. It also does not make any version backups.
You can also set @var{vc-cvs-stay-local} to a regexp that is matched
against the repository hostname; VC then stays local only for
repositories from hosts that match the pattern.
@node SCCS Options
@subsubsection Options specific for SCCS
VC determines the version control state of files under SCCS similar as
under RCS. It does not consider SCCS version headers, though. Thus,
the variable @var{vc-mistrust-permissions} is used in the same way as
under RCS, @pxref{RCS Options} for details.
You can also set @var{vc-cvs-stay-local} to a regular expression
that is matched against the repository hostname; VC then stays local
only for repositories from hosts that match the pattern.
@node Directories
@section File Directories
@ -2789,7 +2796,7 @@ However, not all Dired commands are available in Tar mode.
Tar mode is used also for compressed archives---files with extensions
@samp{.tgz}, @code{.tar.Z} and @code{.tar.gz}.
The keys @kbd{e}, @kbd{f} and @kbd{RET} all extract a component file
The keys @kbd{e}, @kbd{f} and @key{RET} all extract a component file
into its own buffer. You can edit it there and when you save the buffer
the edited version will replace the version in the Tar buffer. @kbd{v}
extracts a file into a buffer in View mode. @kbd{o} extracts the file