merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/Documentation/git-archimport.txt

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+git-archimport(1)
+=================
+
+NAME
+----
+git-archimport - Import a GNU Arch repository into Git
+
+
+SYNOPSIS
+--------
+[verse]
+'git archimport' [-h] [-v] [-o] [-a] [-f] [-T] [-D depth] [-t tempdir]
+               <archive/branch>[:<git-branch>] ...
+
+DESCRIPTION
+-----------
+Imports a project from one or more GNU Arch repositories.
+It will follow branches
+and repositories within the namespaces defined by the <archive/branch>
+parameters supplied. If it cannot find the remote branch a merge comes from
+it will just import it as a regular commit. If it can find it, it will mark it
+as a merge whenever possible (see discussion below).
+
+The script expects you to provide the key roots where it can start the import
+from an 'initial import' or 'tag' type of Arch commit. It will follow and
+import new branches within the provided roots.
+
+It expects to be dealing with one project only. If it sees
+branches that have different roots, it will refuse to run. In that case,
+edit your <archive/branch> parameters to define clearly the scope of the
+import.
+
+'git archimport' uses `tla` extensively in the background to access the
+Arch repository.
+Make sure you have a recent version of `tla` available in the path. `tla` must
+know about the repositories you pass to 'git archimport'.
+
+For the initial import, 'git archimport' expects to find itself in an empty
+directory. To follow the development of a project that uses Arch, rerun
+'git archimport' with the same parameters as the initial import to perform
+incremental imports.
+
+While 'git archimport' will try to create sensible branch names for the
+archives that it imports, it is also possible to specify Git branch names
+manually.  To do so, write a Git branch name after each <archive/branch>
+parameter, separated by a colon.  This way, you can shorten the Arch
+branch names and convert Arch jargon to Git jargon, for example mapping a
+"PROJECT{litdd}devo{litdd}VERSION" branch to "master".
+
+Associating multiple Arch branches to one Git branch is possible; the
+result will make the most sense only if no commits are made to the first
+branch, after the second branch is created.  Still, this is useful to
+convert Arch repositories that had been rotated periodically.
+
+
+MERGES
+------
+Patch merge data from Arch is used to mark merges in Git as well. Git
+does not care much about tracking patches, and only considers a merge when a
+branch incorporates all the commits since the point they forked. The end result
+is that Git will have a good idea of how far branches have diverged. So the
+import process does lose some patch-trading metadata.
+
+Fortunately, when you try and merge branches imported from Arch,
+Git will find a good merge base, and it has a good chance of identifying
+patches that have been traded out-of-sequence between the branches.
+
+OPTIONS
+-------
+
+-h::
+	Display usage.
+
+-v::
+	Verbose output.
+
+-T::
+	Many tags. Will create a tag for every commit, reflecting the commit
+	name in the Arch repository.
+
+-f::
+	Use the fast patchset import strategy.  This can be significantly
+	faster for large trees, but cannot handle directory renames or
+	permissions changes.  The default strategy is slow and safe.
+
+-o::
+	Use this for compatibility with old-style branch names used by
+	earlier versions of 'git archimport'.  Old-style branch names
+	were category{litdd}branch, whereas new-style branch names are
+	archive,category{litdd}branch{litdd}version.  In both cases, names given
+	on the command-line will override the automatically-generated
+	ones.
+
+-D <depth>::
+	Follow merge ancestry and attempt to import trees that have been
+	merged from.  Specify a depth greater than 1 if patch logs have been
+	pruned.
+
+-a::
+	Attempt to auto-register archives at `http://mirrors.sourcecontrol.net`
+	This is particularly useful with the -D option.
+
+-t <tmpdir>::
+	Override the default tempdir.
+
+
+<archive/branch>::
+	Archive/branch identifier in a format that `tla log` understands.
+
+
+GIT
+---
+Part of the linkgit:git[1] suite