Adding upstream version 1:2.39.2.upstream/1%2.39.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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+gitfaq(7)
+=========
+
+NAME
+----
+gitfaq - Frequently asked questions about using Git
+
+SYNOPSIS
+--------
+gitfaq
+
+DESCRIPTION
+-----------
+
+The examples in this FAQ assume a standard POSIX shell, like `bash` or `dash`,
+and a user, A U Thor, who has the account `author` on the hosting provider
+`git.example.org`.
+
+Configuration
+-------------
+
+[[user-name]]
+What should I put in `user.name`?::
+	You should put your personal name, generally a form using a given name
+	and family name.  For example, the current maintainer of Git uses "Junio
+	C Hamano".  This will be the name portion that is stored in every commit
+	you make.
++
+This configuration doesn't have any effect on authenticating to remote services;
+for that, see `credential.username` in linkgit:git-config[1].
+
+[[http-postbuffer]]
+What does `http.postBuffer` really do?::
+	This option changes the size of the buffer that Git uses when pushing
+	data to a remote over HTTP or HTTPS.  If the data is larger than this
+	size, libcurl, which handles the HTTP support for Git, will use chunked
+	transfer encoding since it isn't known ahead of time what the size of
+	the pushed data will be.
++
+Leaving this value at the default size is fine unless you know that either the
+remote server or a proxy in the middle doesn't support HTTP/1.1 (which
+introduced the chunked transfer encoding) or is known to be broken with chunked
+data.  This is often (erroneously) suggested as a solution for generic push
+problems, but since almost every server and proxy supports at least HTTP/1.1,
+raising this value usually doesn't solve most push problems.  A server or proxy
+that didn't correctly support HTTP/1.1 and chunked transfer encoding wouldn't be
+that useful on the Internet today, since it would break lots of traffic.
++
+Note that increasing this value will increase the memory used on every relevant
+push that Git does over HTTP or HTTPS, since the entire buffer is allocated
+regardless of whether or not it is all used.  Thus, it's best to leave it at the
+default unless you are sure you need a different value.
+
+[[configure-editor]]
+How do I configure a different editor?::
+	If you haven't specified an editor specifically for Git, it will by default
+	use the editor you've configured using the `VISUAL` or `EDITOR` environment
+	variables, or if neither is specified, the system default (which is usually
+	`vi`).  Since some people find `vi` difficult to use or prefer a different
+	editor, it may be desirable to change the editor used.
++
+If you want to configure a general editor for most programs which need one, you
+can edit your shell configuration (e.g., `~/.bashrc` or `~/.zshenv`) to contain
+a line setting the `EDITOR` or `VISUAL` environment variable to an appropriate
+value.  For example, if you prefer the editor `nano`, then you could write the
+following:
++
+----
+export VISUAL=nano
+----
++
+If you want to configure an editor specifically for Git, you can either set the
+`core.editor` configuration value or the `GIT_EDITOR` environment variable.  You
+can see linkgit:git-var[1] for details on the order in which these options are
+consulted.
++
+Note that in all cases, the editor value will be passed to the shell, so any
+arguments containing spaces should be appropriately quoted.  Additionally, if
+your editor normally detaches from the terminal when invoked, you should specify
+it with an argument that makes it not do that, or else Git will not see any
+changes.  An example of a configuration addressing both of these issues on
+Windows would be the configuration `"C:\Program Files\Vim\gvim.exe" --nofork`,
+which quotes the filename with spaces and specifies the `--nofork` option to
+avoid backgrounding the process.
+
+Credentials
+-----------
+
+[[http-credentials]]
+How do I specify my credentials when pushing over HTTP?::
+	The easiest way to do this is to use a credential helper via the
+	`credential.helper` configuration.  Most systems provide a standard
+	choice to integrate with the system credential manager.  For example,
+	Git for Windows provides the `wincred` credential manager, macOS has the
+	`osxkeychain` credential manager, and Unix systems with a standard
+	desktop environment can use the `libsecret` credential manager.  All of
+	these store credentials in an encrypted store to keep your passwords or
+	tokens secure.
++
+In addition, you can use the `store` credential manager which stores in a file
+in your home directory, or the `cache` credential manager, which does not
+permanently store your credentials, but does prevent you from being prompted for
+them for a certain period of time.
++
+You can also just enter your password when prompted.  While it is possible to
+place the password (which must be percent-encoded) in the URL, this is not
+particularly secure and can lead to accidental exposure of credentials, so it is
+not recommended.
+
+[[http-credentials-environment]]
+How do I read a password or token from an environment variable?::
+	The `credential.helper` configuration option can also take an arbitrary
+	shell command that produces the credential protocol on standard output.
+	This is useful when passing credentials into a container, for example.
++
+Such a shell command can be specified by starting the option value with an
+exclamation point.  If your password or token were stored in the `GIT_TOKEN`,
+you could run the following command to set your credential helper:
++
+----
+$ git config credential.helper \
+	'!f() { echo username=author; echo "password=$GIT_TOKEN"; };f'
+----
+
+[[http-reset-credentials]]
+How do I change the password or token I've saved in my credential manager?::
+	Usually, if the password or token is invalid, Git will erase it and
+	prompt for a new one.  However, there are times when this doesn't always
+	happen.  To change the password or token, you can erase the existing
+	credentials and then Git will prompt for new ones.  To erase
+	credentials, use a syntax like the following (substituting your username
+	and the hostname):
++
+----
+$ echo url=https://author@git.example.org | git credential reject
+----
+
+[[multiple-accounts-http]]
+How do I use multiple accounts with the same hosting provider using HTTP?::
+	Usually the easiest way to distinguish between these accounts is to use
+	the username in the URL.  For example, if you have the accounts `author`
+	and `committer` on `git.example.org`, you can use the URLs
+	https://author@git.example.org/org1/project1.git and
+	https://committer@git.example.org/org2/project2.git.  This way, when you
+	use a credential helper, it will automatically try to look up the
+	correct credentials for your account.  If you already have a remote set
+	up, you can change the URL with something like `git remote set-url
+	origin https://author@git.example.org/org1/project1.git` (see
+	linkgit:git-remote[1] for details).
+
+[[multiple-accounts-ssh]]
+How do I use multiple accounts with the same hosting provider using SSH?::
+	With most hosting providers that support SSH, a single key pair uniquely
+	identifies a user.  Therefore, to use multiple accounts, it's necessary
+	to create a key pair for each account.  If you're using a reasonably
+	modern OpenSSH version, you can create a new key pair with something
+	like `ssh-keygen -t ed25519 -f ~/.ssh/id_committer`.  You can then
+	register the public key (in this case, `~/.ssh/id_committer.pub`; note
+	the `.pub`) with the hosting provider.
++
+Most hosting providers use a single SSH account for pushing; that is, all users
+push to the `git` account (e.g., `git@git.example.org`).  If that's the case for
+your provider, you can set up multiple aliases in SSH to make it clear which key
+pair to use.  For example, you could write something like the following in
+`~/.ssh/config`, substituting the proper private key file:
++
+----
+# This is the account for author on git.example.org.
+Host example_author
+	HostName git.example.org
+	User git
+	# This is the key pair registered for author with git.example.org.
+	IdentityFile ~/.ssh/id_author
+	IdentitiesOnly yes
+# This is the account for committer on git.example.org.
+Host example_committer
+	HostName git.example.org
+	User git
+	# This is the key pair registered for committer with git.example.org.
+	IdentityFile ~/.ssh/id_committer
+	IdentitiesOnly yes
+----
++
+Then, you can adjust your push URL to use `git@example_author` or
+`git@example_committer` instead of `git@example.org` (e.g., `git remote set-url
+git@example_author:org1/project1.git`).
+
+Common Issues
+-------------
+
+[[last-commit-amend]]
+I've made a mistake in the last commit.  How do I change it?::
+	You can make the appropriate change to your working tree, run `git add
+	<file>` or `git rm <file>`, as appropriate, to stage it, and then `git
+	commit --amend`.  Your change will be included in the commit, and you'll
+	be prompted to edit the commit message again; if you wish to use the
+	original message verbatim, you can use the `--no-edit` option to `git
+	commit` in addition, or just save and quit when your editor opens.
+
+[[undo-previous-change]]
+I've made a change with a bug and it's been included in the main branch.  How should I undo it?::
+	The usual way to deal with this is to use `git revert`.  This preserves
+	the history that the original change was made and was a valuable
+	contribution, but also introduces a new commit that undoes those changes
+	because the original had a problem.  The commit message of the revert
+	indicates the commit which was reverted and is usually edited to include
+	an explanation as to why the revert was made.
+
+[[ignore-tracked-files]]
+How do I ignore changes to a tracked file?::
+	Git doesn't provide a way to do this.  The reason is that if Git needs
+	to overwrite this file, such as during a checkout, it doesn't know
+	whether the changes to the file are precious and should be kept, or
+	whether they are irrelevant and can safely be destroyed.  Therefore, it
+	has to take the safe route and always preserve them.
++
+It's tempting to try to use certain features of `git update-index`, namely the
+assume-unchanged and skip-worktree bits, but these don't work properly for this
+purpose and shouldn't be used this way.
++
+If your goal is to modify a configuration file, it can often be helpful to have
+a file checked into the repository which is a template or set of defaults which
+can then be copied alongside and modified as appropriate.  This second, modified
+file is usually ignored to prevent accidentally committing it.
+
+[[files-in-gitignore-are-tracked]]
+I asked Git to ignore various files, yet they are still tracked::
+	A `gitignore` file ensures that certain file(s) which are not
+	tracked by Git remain untracked.  However, sometimes particular
+	file(s) may have been tracked before adding them into the
+	`.gitignore`, hence they still remain tracked.  To untrack and
+	ignore files/patterns, use `git rm --cached <file/pattern>`
+	and add a pattern to `.gitignore` that matches the <file>.
+	See linkgit:gitignore[5] for details.
+
+[[fetching-and-pulling]]
+How do I know if I want to do a fetch or a pull?::
+	A fetch stores a copy of the latest changes from the remote
+	repository, without modifying the working tree or current branch.
+	You can then at your leisure inspect, merge, rebase on top of, or
+	ignore the upstream changes.  A pull consists of a fetch followed
+	immediately by either a merge or rebase.  See linkgit:git-pull[1].
+
+Merging and Rebasing
+--------------------
+
+[[long-running-squash-merge]]
+What kinds of problems can occur when merging long-lived branches with squash merges?::
+	In general, there are a variety of problems that can occur when using squash
+	merges to merge two branches multiple times.  These can include seeing extra
+	commits in `git log` output, with a GUI, or when using the `...` notation to
+	express a range, as well as the possibility of needing to re-resolve conflicts
+	again and again.
++
+When Git does a normal merge between two branches, it considers exactly three
+points: the two branches and a third commit, called the _merge base_, which is
+usually the common ancestor of the commits.  The result of the merge is the sum
+of the changes between the merge base and each head.  When you merge two
+branches with a regular merge commit, this results in a new commit which will
+end up as a merge base when they're merged again, because there is now a new
+common ancestor.  Git doesn't have to consider changes that occurred before the
+merge base, so you don't have to re-resolve any conflicts you resolved before.
++
+When you perform a squash merge, a merge commit isn't created; instead, the
+changes from one side are applied as a regular commit to the other side.  This
+means that the merge base for these branches won't have changed, and so when Git
+goes to perform its next merge, it considers all of the changes that it
+considered the last time plus the new changes.  That means any conflicts may
+need to be re-resolved.  Similarly, anything using the `...` notation in `git
+diff`, `git log`, or a GUI will result in showing all of the changes since the
+original merge base.
++
+As a consequence, if you want to merge two long-lived branches repeatedly, it's
+best to always use a regular merge commit.
+
+[[merge-two-revert-one]]
+If I make a change on two branches but revert it on one, why does the merge of those branches include the change?::
+	By default, when Git does a merge, it uses a strategy called the `ort`
+	strategy, which does a fancy three-way merge.  In such a case, when Git
+	performs the merge, it considers exactly three points: the two heads and a
+	third point, called the _merge base_, which is usually the common ancestor of
+	those commits.  Git does not consider the history or the individual commits
+	that have happened on those branches at all.
++
+As a result, if both sides have a change and one side has reverted that change,
+the result is to include the change.  This is because the code has changed on
+one side and there is no net change on the other, and in this scenario, Git
+adopts the change.
++
+If this is a problem for you, you can do a rebase instead, rebasing the branch
+with the revert onto the other branch.  A rebase in this scenario will revert
+the change, because a rebase applies each individual commit, including the
+revert.  Note that rebases rewrite history, so you should avoid rebasing
+published branches unless you're sure you're comfortable with that.  See the
+NOTES section in linkgit:git-rebase[1] for more details.
+
+Hooks
+-----
+
+[[restrict-with-hooks]]
+How do I use hooks to prevent users from making certain changes?::
+	The only safe place to make these changes is on the remote repository
+	(i.e., the Git server), usually in the `pre-receive` hook or in a
+	continuous integration (CI) system.  These are the locations in which
+	policy can be enforced effectively.
++
+It's common to try to use `pre-commit` hooks (or, for commit messages,
+`commit-msg` hooks) to check these things, which is great if you're working as a
+solo developer and want the tooling to help you.  However, using hooks on a
+developer machine is not effective as a policy control because a user can bypass
+these hooks with `--no-verify` without being noticed (among various other ways).
+Git assumes that the user is in control of their local repositories and doesn't
+try to prevent this or tattle on the user.
++
+In addition, some advanced users find `pre-commit` hooks to be an impediment to
+workflows that use temporary commits to stage work in progress or that create
+fixup commits, so it's better to push these kinds of checks to the server
+anyway.
+
+Cross-Platform Issues
+---------------------
+
+[[windows-text-binary]]
+I'm on Windows and my text files are detected as binary.::
+	Git works best when you store text files as UTF-8.  Many programs on
+	Windows support UTF-8, but some do not and only use the little-endian
+	UTF-16 format, which Git detects as binary.  If you can't use UTF-8 with
+	your programs, you can specify a working tree encoding that indicates
+	which encoding your files should be checked out with, while still
+	storing these files as UTF-8 in the repository.  This allows tools like
+	linkgit:git-diff[1] to work as expected, while still allowing your tools
+	to work.
++
+To do so, you can specify a linkgit:gitattributes[5] pattern with the
+`working-tree-encoding` attribute.  For example, the following pattern sets all
+C files to use UTF-16LE-BOM, which is a common encoding on Windows:
++
+----
+*.c	working-tree-encoding=UTF-16LE-BOM
+----
++
+You will need to run `git add --renormalize` to have this take effect.  Note
+that if you are making these changes on a project that is used across platforms,
+you'll probably want to make it in a per-user configuration file or in the one
+in `$GIT_DIR/info/attributes`, since making it in a `.gitattributes` file in the
+repository will apply to all users of the repository.
++
+See the following entry for information about normalizing line endings as well,
+and see linkgit:gitattributes[5] for more information about attribute files.
+
+[[windows-diff-control-m]]
+I'm on Windows and git diff shows my files as having a `^M` at the end.::
+	By default, Git expects files to be stored with Unix line endings.  As such,
+	the carriage return (`^M`) that is part of a Windows line ending is shown
+	because it is considered to be trailing whitespace.  Git defaults to showing
+	trailing whitespace only on new lines, not existing ones.
++
+You can store the files in the repository with Unix line endings and convert
+them automatically to your platform's line endings.  To do that, set the
+configuration option `core.eol` to `native` and see the following entry for
+information about how to configure files as text or binary.
++
+You can also control this behavior with the `core.whitespace` setting if you
+don't wish to remove the carriage returns from your line endings.
+
+[[always-modified-files-case]]
+Why do I have a file that's always modified?::
+	Internally, Git always stores file names as sequences of bytes and doesn't
+	perform any encoding or case folding.  However, Windows and macOS by default
+	both perform case folding on file names.  As a result, it's possible to end up
+	with multiple files or directories whose names differ only in case.  Git can
+	handle this just fine, but the file system can store only one of these files,
+	so when Git reads the other file to see its contents, it looks modified.
++
+It's best to remove one of the files such that you only have one file.  You can
+do this with commands like the following (assuming two files `AFile.txt` and
+`afile.txt`) on an otherwise clean working tree:
++
+----
+$ git rm --cached AFile.txt
+$ git commit -m 'Remove files conflicting in case'
+$ git checkout .
+----
++
+This avoids touching the disk, but removes the additional file.  Your project
+may prefer to adopt a naming convention, such as all-lowercase names, to avoid
+this problem from occurring again; such a convention can be checked using a
+`pre-receive` hook or as part of a continuous integration (CI) system.
++
+It is also possible for perpetually modified files to occur on any platform if a
+smudge or clean filter is in use on your system but a file was previously
+committed without running the smudge or clean filter.  To fix this, run the
+following on an otherwise clean working tree:
++
+----
+$ git add --renormalize .
+----
+
+[[recommended-storage-settings]]
+What's the recommended way to store files in Git?::
+	While Git can store and handle any file of any type, there are some
+	settings that work better than others.  In general, we recommend that
+	text files be stored in UTF-8 without a byte-order mark (BOM) with LF
+	(Unix-style) endings.  We also recommend the use of UTF-8 (again,
+	without BOM) in commit messages.  These are the settings that work best
+	across platforms and with tools such as `git diff` and `git merge`.
++
+Additionally, if you have a choice between storage formats that are text based
+or non-text based, we recommend storing files in the text format and, if
+necessary, transforming them into the other format.  For example, a text-based
+SQL dump with one record per line will work much better for diffing and merging
+than an actual database file.  Similarly, text-based formats such as Markdown
+and AsciiDoc will work better than binary formats such as Microsoft Word and
+PDF.
++
+Similarly, storing binary dependencies (e.g., shared libraries or JAR files) or
+build products in the repository is generally not recommended.  Dependencies and
+build products are best stored on an artifact or package server with only
+references, URLs, and hashes stored in the repository.
++
+We also recommend setting a linkgit:gitattributes[5] file to explicitly mark
+which files are text and which are binary.  If you want Git to guess, you can
+set the attribute `text=auto`.  For example, the following might be appropriate
+in some projects:
++
+----
+# By default, guess.
+*	text=auto
+# Mark all C files as text.
+*.c	text
+# Mark all JPEG files as binary.
+*.jpg	binary
+----
++
+These settings help tools pick the right format for output such as patches and
+result in files being checked out in the appropriate line ending for the
+platform.
+
+GIT
+---
+Part of the linkgit:git[1] suite