NAME

       acngfs - Virtual file system for use with apt-cacher-ng

SYNOPSIS

       acngfs BaseURL ProxyHost [CachePath] MountPoint [-o FUSE Mount Options]

DESCRIPTION

       acngfs  is a FUSE based filesystem which represents files downloadable via HTTP as part of
       a local filesystem. It has been developed for very specific purposes and is  not  intended
       to be a general purpose HTTP filesystem.

       The main use case for acngfs is a situation where:

       •      The  files  must not be stored on extra space on the user's system (e.g. because of
              insufficient disk space to make a temporary copy of downloaded files)

       •      Local programs (e.g. apt, dpkg) need to read the packages from a local filesystem

       •      When reading, certain files might need to be fetched in background (or updated) and
              this process needs to be triggered somehow

       •      Network  latency  and  speed  are  not  relevant,  e.g. accessing apt-cacher-ng via
              localhost connection

       •      The proxy service can work efficiently with many requests  for  small  data  ranges
              (apt-cacher-ng, for example)

       •      Pattern matching on paths is sufficient to distinguish file and directory names

       If  the  apt-cacher-ng  instance  happens to run on the same system as acngfs or its cache
       repository is mounted via fast remote file system, this cache repository can be optionally
       specified  as  alternative  source  path. In this cache, acngfs will attempt to read files
       directly from this filesystem  where  possible,  reducing  network  latency  and  avoiding
       additional  load  of  apt-cacher-ng  server. The directory levels of BaseURL and CachePath
       should match.

EXAMPLES

       Typical use may be to let apt/dpkg use package file like they are  present  on  the  local
       filesystem  so there is no need to download them. In sources.list, the source appears as a
       file:/ type URL, like:

       deb file:/var/local/acngfs_debian unstable main contrib

       and the filesystem backend is prepared with a command like:

       /usr/lib/apt-cacher-ng/acngfs          http://ftp.uni-kl.de/debian           cacheBox:3142
       /var/local/acngfs_debian -o allow_root

       or  for  a  locally  installed apt-cacher-ng with common Debian cache repository stored in
       /var/cache/apt-cacher-ng/debrep:

       /usr/lib/apt-cacher-ng/acngfs http://ftp.uni-kl.de/debian  localhost:3142  /var/cache/apt-
       cacher-ng/debrep /var/local/acngfs_debian -o allow_root

OPTIONS

       The command-line options supported by acngfs are:

       BaseURL
              Remote  mirror  to  be  used as real source, like http://ftp2.de.debian.org/debian.
              NOTE: the mirror subdirectory part (like debian) should be added either to  BaseURL
              or to the path in sources.list, not to both.

       ProxyURL
              Complete   or   simplified  host  and  port  specification  of  the  proxy  server,
              http://localhost:3142.

       CachePath
              Optional hint, a directory path pointing to the internal cache subdirectory of apt-
              cacher-ng  where  it stores data downloaded from BaseURL. For more details see apt-
              cacher-ng manual, chapter "Advanced configuration".

       mountpoint
              Directory representing the URL in the local filesytem.

       --help Print a help summary and additional FUSE application options

       FuseOptions
              Various options for the FUSE subsystem to control filesystem behaviour. See  --help
              output and FUSE documentation for more details.

FILES

       /usr/lib/apt-cacher-ng/acngfs
              Executable binary documented in this manual page

NOTES

       Permissions  of  the  files are important when using mounting when sharing data with other
       users (including root!). To mount as user and let root use the  package  management  tools
       (apt, dpkg), one may need to use FUSE options like in the following example:

       acngfs http://ftp.uni-kl.de/debian http://localhost:3142 /mnt/misc -o allow_root

       See FUSE documentation for details about file permissions representation.

BUGS

       Software is still experimental, use at your own risk!

       There  are natural limitations on capabilities of the FS: no directory browsing is allowed
       (only blind descending), permissions of files are inherited from the mount point  as  well
       as other properties of the filesystem.

       Should  be  used with apt-cacher-ng version 0.2pre2 or newer; otherwise it could flood log
       files with many requests from small file chunks.

SEE ALSO

       apt-cacher-ng(8), fusermount(1)

       For more information on Apt-Cacher NG, read the User Manual which can be found  either  in
       the  doc/pdf  directory  of  the software source package or installed in the documentation
       directory of apt-cacher-ng by your distribution.