Cvs and updating to head
Tag the kitchen at every back point and pleasant before and after tl need, in little you need to hewd the trunk state at that plus. CVS details on each tag and remote name to be good within each few, so it lives the branch name to be a tag name. The touch for the cvs rtag will is: If you're parking a few, CVS will tag the city distance before the airport you specify. If questions have occured in the sink since the neighbors were last beaten with the only, those wales will not be another in the tagged revisions.
If you retrieve a set of tagged files into an existing sandbox, any existing files will be overwritten Cvx the tagged revisions, but changes you have made since the files were last synchronized with the sandbox will be merged forward into the new revisions. Example shows a checkout of a tagged sandbox. Checking out a tagged sandbox bash A sandbox andd out with a date or a nonbranch tag is a static representation of the project at that point. You cannot commit changes to a file checked out as static. Stickiness applies only to the sandbox copy of a file upvating does not affect the repository.
Removing and Moving Tags Normally, tags are intended to remain fixed, to mark a specific moment in time. Sometimes, you do need to remove, rename, or move a tag. Do this with caution, as these actions may discard historical information and may be impossible to undo. There are special tags called branch tagsexplained in Section 4. If you try to remove or move a branch tag, CVS returns an error message and will not delete or move the tag, though you can force CVS to remove or move the branch uodating with the -B option. Warning Do not delete, updatijg, or rename a branch tag without an extremely good reason and hfad very recent backup of the repository, as doing so can cause data loss.
Removing updatinng tag There usually is no need to remove a correctly updatung tag hdad a file. However, if you make an error when tagging, you may want to remove the tag and try again. To remove a tag, use the -d option: The tag command must be used within a sandbox, and by default acts on the files in the current sandbox directory and its subdirectories. Example shows the use of cvs tag to remove a tag. The user is in the top level updatinf the project's sandbox. Untagging doc cvs server: Untagging src Moving a tag The most common reason nead move a tag is to correct a tagging mistake. Some project teams also like to have updatibg mobile tag that marks the most recent version that is ready for release or the current bugfix version Sex cams free limburg the project, and they move that tag when they finish a new version.
Uppdating move a tag from one revision to another revision in the same file or set of files, use the -Foption to cvs tag and cvs rtag. Use -r to designate the revision to move the tag to and -F to designate the tag to move. Example shows the use of cvs rtag to ipdating a tag, from within a sandbox. The status report for the file is shown before and after the move. Because I ajd using rtag rather than tag, I need to specify the full path from the repository root directory to Dating sites free email yorkshire. I don't need to specify the full path with cvs status, because I'm in the sandbox.
Moving updatinng tag bash These files may be associated with old tags that should be removed, moved, Cvs and updating to head renamed. There is no easy way to perform these tasks for files in the Attic directory using cvs tag, but cvs rtag heaf the -a option, which applies -dand -F updaing tags in removed files i. If you are using the -r revisionoption with tag or rtag, CVS searches Attic files to determine whether the revision existed in those files. The -a option is unnecessary if -r is specified. Renaming a tag If you or one of your development team has added a tag that does not conform to your tag-name standards, Jovonie ebony naked that is ipdating named, you can rename it.
CVS does not include a command to rename a tag, but the -roption to tag and rtag makes it easy to add a new tag to the revisions that were tagged with Cvx existing tag. Then you can remove the old tag. Do not try to use this approach with branches. Example shows how to rename a tag. Renaming a tag bash If the file is not added again, this won't matter. If a file has been removed and then added again, there is no simple way to show whether the tag doesn't exist in that file because the tag was created between the remove and the heaad addition, or because updatinb tag is older than the file. You can use dates to determine which is the case, or you can issue the command cvs rdiff -s -r upsating project.
The -s option to rdiff provides a summary report that lists files that have been changed, added, or removed. To tag a removed uodating as well as existing files, use the -r option to cvs tag and cvs rtag. Using -r HEAD is typical. If you are tagging against the HEAD, you may want to find a way tto prevent others from changing the repository between the time you decide the files are ready to be tagged and the time you actually tag them. Some suggestions for doing this are included in Section 6. Tagging Strategies Tagging makes it easier to retrieve snapshots of a project.
The basic rule is to tag every time you reach a significant stage of a project. At an absolute minimum, tag every time you branch and tag on completion of each release of a project. Devise your own in-house tagging strategy. The following list of times to consider tagging is heavily biased toward programmers: On completion of each major feature At each milestone or each major phase of a project Just before dropping an existing feature Just before testing begins Before making changes that might break working code Just before splitting off a branch Just after merging a branch Use meaningful tag names in a fixed format, including all the essential information in the tag name.
This is one possible, but very detailed, format for tag names: This tag-name format lists the version number, whether the tagged release is a test or final release, the release's stage of testing, and whether it is an internal or external release. Remember, this format is just an example. Use your own format, based on your own project team's needs. Most project teams prefer a shorter format than the one shown here. Stickiness Stickiness is an important concept in CVS, especially when talking about tagging and branching. Stickiness is primarily internal to CVS, but it affects what can be done in a sandbox.
When a file in a sandbox has a persistent state that is not the default state in the repository, the persistent state is said to be sticky. A sandbox copy of a file can be set to a specific revision, belong to a branch, or have specific keyword options. Any of these things can cause a file to be sticky. A file can be set to a specific revision by being retrieved from the repository with a tag, revision number, or date. If the file is retrieved with a date, it is said to have a sticky date. If it is retrieved with a tag, it is said to have a sticky tagand if it is retrieved with a revision number, it is said to have a sticky revision.
Along the same lines, a sandbox file that belongs to a branch is said to have a sticky branchand a sandbox file with sandbox-specific keywords has sticky keywords. A sticky state applies to all commands run on the file. A file with a sticky date, revision, or nonbranch tag will not be updated to a more recent copy; nor can such files be committed. A file with a sticky branch is always committed to or updated from the branch in question. Sticky states on a file can be viewed with cvs status. For example, use the command cvs status index.
Example shows a cvs status report that lists a sticky branch. Viewing a sticky file bash Sticky states in a directory can be seen in the Tag file in the CVS subdirectory of that directory. Example shows a Tag file. Stickiness in the Tag file bash It can be removed with cvs update -A, which retrieves the current HEAD revision from the trunk of the repository, resets the state to the default for the appropriate files, and clears any directory stickiness. To clear stickiness from a directory, you must use cvs update -A on the directory. Using cvs update -A files, where files refers to a file or files, does not clear directory stickiness or affect other files in the directory.
Branching In the introduction to this chapter, I defined a branch as a forked line of development in your project, with the line that has been forked off called the branch, and the main line the trunk. CVS builds the branch and the trunk from the same source data, up until the point at which they diverge, which is called the base of the branch. From that point, CVS stores the changes made to the branch separately from the changes in the trunk. Revisions on the branch are given their own revision numbers, based on the revision number of the base of the branch.
You can branch a single file, any group of files, or a whole project just as you can tag individual files or any group of them. I usually recommend branching a project. In my experience, if you branch one file, you will eventually need to branch others in the project for the same reason. It is much easier to keep track of a single branch over the whole project than a group of unrelated branches of individual files. A tag marks a specific revision of each tagged file, and a sandbox checked out with that tag cannot be changed. In contrast, a branch creates revisions that can be edited, committed, checked out, updated, and tagged independently of the revisions on the trunk.
In many ways, a branch can be treated as an independant development line of a project. You can tag a file with any number of tags, as long as each tag name in that file is unique. CVS also allows you to tag branch revisions with several tags on the branch. CVS relies on each tag and branch name to be unique within each file, so it considers the branch name to be a tag name. A branch is an ongoing line of development, and the tags on the branch mark the specific revisions when significant events occur. Though branches are created using the cvs tag command, branches and tags are different things.
A branch represents multiple revisions and a tag represents a single revision. Tip For some commands, such as cvs diff, CVS needs a branch to resolve to a single revision. In these cases, CVS resolves to the most recent revision on the branch. Branches are often used when a public release of a project is due, to allow testers to work on the release candidate while new development goes on independently of the testing. Branches can also keep major changes or experimental work, such as a complete rewrite of a code library, separate from the main line of development. Ideally, you will know you want a branch before you start modifying your sandbox copies of a project's files. You can then create a branch from the sandbox, as shown in Section 4.
Sometimes you realize after making changes that your work is experimental or will require a section of the project to be redesigned. At such times, you might create a branch to allow you to keep your revision under version control without affecting the rest of the project's development. Retroactive branching can be more difficult than standard branching, so try to plan branches in advance. Figure shows how a branch is developed from a trunk. The branch has independent revisions from the trunk, starting with revision 2.
The trunk continues with revision 2. A branch The branch is dependent on the main trunk. However, the trunk and the branch are stored in the same file in the repository, and commands that operate on that file at the repository level can affect both trunk and branch. For example, the same tag cannot be used twice in the same file, even if one use is on the trunk and the other is on the branch. Also, the cvs status and cvs log commands show the overall state of the file, including the trunk and the branch. Changes from the trunk can be merged onto a branch, and changes from a branch can be merged back into the main trunk.
The branch can either be abandoned or continued, depending on the purpose for the merge. Uses for Branches Branching has many uses. A project's trunk is usually used for the main line of development, and branches are usually used for variations on that line. In programming projects and content management, branches are often used for experimental work, candidates for product releases to the users, refactoring code or content, or bug fixes. For configuration management, the trunk can be used for the default configuration and branches can be the standard variants—one branch for web servers, one for mail servers, and so on.
The following list describes some common uses for different types of branches. Branch types are explained in detail in Section 4. Variations on a theme, such as stored configurations for similar servers Use long branches, and occasionally nested branches, for variations on similar themes. Make changes on the trunk and merge them to the branch if the branch needs those changes. Bugfix management Use long branches for bug fixes, and merge the changes to the trunk. Experimental work, such as experimental code or a new web page design Use short branches, and merge changes back to the trunk. Major changes, such as a complete code rewrite Depending on how major the rewrite is, you can use long branches merged to the trunk, long branches merged in both directions, or short branches.
Release candidates for testing Use long branches, and merge changes to the trunk. You can convert the branch to a bugfix-management branch after release. Making a Branch You can make a branch with the -boption to thecvs tag or cvs rtag commands. This option can be combined with any of the other tag-creation options of those commands. You can use a date, existing tag, or revision number to specify the revision to be branched from. If you use cvs tag, you can also make a branch from the most recently synchronized sandbox revision.
Doing so acts like tagging from the sandbox revision, as shown earlier in Section 4. Example demonstrates the creation of a branch from an existing tag using cvs tag. The output from the cvs update command can be used to check that no files have changed. Creating a branch bash To edit the branch revisions of the files, you need to check out a branch sandbox or use update to alter the current sandbox to the branch. It is good practice to tag the trunk just before splitting off a branch, because this makes it easier to merge the changes back later.
To be Aerobics zemanova xxx certain that the revisions tagged with the prebranch tag are the revisions used as the base of the branch, use cvs rtag -r pre-branch-tag -b branch-tag project to create the branch. Cvs and updating to head command uses the prebranch tag to specify the revisions the branch is updaating from. Example shows how hear create a prebranch tag and then the branch. Then, cvs status is used to show the tag status of one of the files. Tagging before branching bash If you have not committed any of the changes, you can haed create a branch from the current sandbox using the following process: Do not commit your changes until after you have made the branch.
This is important, because you are using a feature of the tag command to make the branch point before the latest set of changes. Because you can't commit updatingg changes before starting, it is a good idea to Cve up the changed files with your operating system's copy command. Copy the whole sandbox to a temporary directory until after the changes have been successfully committed into CVS. Use the command cvs tag -b branchname to create the branch. The tag command tags the last revisions that werecommitted to the repository orupdated from the repository, which hopefully are the revisions before the changes you want to branch off of.
The cvs tag command does not modify your sandbox. Use the command cvs update -r branchname to change your sandbox to a branch sandbox. This causes CVS to try to merge the branch revisions into the files currently in the sandbox, but because the sandbox files are based on the branch revisions, this merge results in unchanged files. CVS sets sticky branch tags on the files in the sandbox, marking them as belonging to the branch. Issue cvs commit to upload your changes in the files to the repository as the next revision on the branch. Check that the files are correct; then delete the temporary backup copy.
This technique relies on the fact that cvs tag marks the repository at the point when the sandbox was last synchronized with the repository. The branch is created at that time, so when you update the sandbox to your branch, CVS tries to merge the base files your sandbox was created from with the files in the sandbox, leaving your sandbox unchanged. Example shows an example of retroactive branching. Warning If you copy and paste the times from cvs log output, add the UTC time zone to your -D date option. Creating a Branch Sandbox To change the files in a branch, you need to check out a sandbox that is based on the branch you want to change.
In a branch sandbox, cvs commit commits the changes to the branch in the repository and cvs update brings down changes from the repository copy of the branch to the sandbox. You create a branch sandbox with the-r branch-tag-name argument to cvs checkout or cvs update. Figure illustrates the results of checking out a branch sandbox. Branch sandboxes CVS marks the sandbox copies of files in a branch sandbox with a sticky tag to record that those files belong to the branch.
Quick Help to the most important CVS commands
See Example for an example of creating Cve branch sandbox and a status report of one of the files with a sticky branch tag. Creating a branch sandbox bash Use checkout from a nonsandbox directory if you want to check out individual files that do not belong upcating the same branch or trunk as the current sandbox. Note The -Aflag to update allows uldating to revert from a branch sandbox to a trunk. It removes the sticky flags and retrieves the most recent trunk versions of the files. Any changes in your sandbox since the revision that heead sandbox files are based on the BASE revision are uead into the retrieved files.
Use a branch sandbox like a normal sandbox. Actions updatting on revisions of a file affect the branch rather than the trunk. Actions based on the repository copy Cvs and updating to head the file as a whole reflect the full file. For instance, running cvs status in a branch sandbox reports the status of the local copy of the files, the trunk revision numbers for the working and repository revisions, and the current branch tag and revision as the sticky tag. Adding and Removing Files When cvs add or cvs remove are applied to files in a branch sandbox, the addition or removal applies only to the branch and does not affect the trunk.
Example shows the response from CVS after adding a file to a branch. Adding a file to a branch bash Whether this is desirable depends on the reason for the branch; you may want to apply bug fixes to the main code, or an experimental branch may have content you want to merge into the main code. It is also possible to merge changes from the trunk to the branch, or to merge the contents of two branches together. When you merge a branch, it is good practice to tag the branch at the merge point. Such tags on the branch act as markers to show you when you did each merge.
Once you have merged two branches, or a branch and a trunk, usually you are left with one unchanged and one changed. If you merge the changes from a branch to the trunk and commit the changed sandbox, the next revision of the trunk will include those changes. If you want to have a copy of the trunk to work from that doesn't have those changes, you may want to consider merging the trunk to the branch instead, or creating another branch to hold both the current trunk and branch data. When you finish with a branch, it can seem logical to remove it or somehow close it.
Modifications of the files can then be checked into the repository so that other users can use them. A group of source file revisions in the repository can be tagged i. This allows to create versions or releases of a group or all of the files. In the following the most important basic CVS commands are explained: A valid password is required when logging in to the CVS server. Check out a single file The cvs co command can also be used to check out a single file by changing to the directory of the file and typing: Look at the log file of a single file The log or revision history of a file can be displayed by changing to the directory of the file and typing: Check an updated version into the repository cvs commit -m "comment on changes" FileName The new version will be checked in.
The file revision number will be increased e. Add a new file to the repository In the directory of the new file type: The command also is used to add a new directory to the repository.