ostree/man/rofiles-fuse.xml

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XML

<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
Copyright 2016 Colin Walters <walters@verbum.org>
SPDX-License-Identifier: LGPL-2.0+
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<refentry id="ostree">
<refentryinfo>
<title>rofiles-fuse</title>
<productname>rofiles-fuse</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Colin</firstname>
<surname>Walters</surname>
<email>walters@verbum.org</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>rofiles-fuse</refentrytitle>
<manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
<refname>rofiles-fuse</refname>
<refpurpose>Use FUSE to create a view where directories are writable, files are immutable</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>rofiles-fuse SRCDIR MNTPOINT</command>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>
Creating a checkout from an OSTree repository by default
uses hard links, which means an in-place mutation to any
file corrupts the repository and all checkouts. This can be
problematic if one wishes to run arbitrary programs against
such a checkout. For example, RPM <literal>%post</literal>
scripts or equivalent.
</para>
<para>
In the case where one wants to create a tree commit derived
from other content, using <command>rofiles-fuse</command> in
concert with <command>ostree commit
--link-checkout-speedup</command> (or the underlying API)
can ensure that only new files are checksummed.
</para>
</refsect1>
<refsect1>
<title>Example: Update an OSTree commit</title>
<programlisting>
# Initialize a checkout and mount
$ ostree --repo=repo checkout somebranch branch-checkout
$ mkdir mnt
$ rofiles-fuse branch-checkout mnt
# Now, arbitrary changes to mnt/ are reflected in branch-checkout
$ echo somenewcontent > mnt/anewfile
$ mkdir mnt/anewdir
$ rm mnt/someoriginalcontent -rf
# Commit and cleanup
$ fusermount -u mnt
$ ostree --repo=repo commit --link-checkout-speedup -b somebranch -s 'Commit new content' --tree=dir=branch-checkout
$ rm mnt branch-checkout -rf
</programlisting>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>ostree</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>