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[apt.git] / doc / sources.list.5.yo

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manpage(sources.list)(5)(5 Dec 1998)(apt)()
manpagename(sources.list)(package resource list for APT)

manpagedescription()
The package resource list is used to locate archives of the package
distribution system in use on the system. At this time, this manual page
documents only the packaging system used by the Debian GNU/Linux system.

The source list is designed to support any number of active sources and a
variety of source media. The file lists one source per line, with the
most preferred source listed first. The format of each line is:
em(type uri args) The first item, em(type), determines the format for
em(args). em(uri) is a Universal Resource Identifier (URI), which is a 
superset of the more specific and well-known Universal Resource Locator, or 
URL.

manpagesection(The deb type)
The bf(deb) type describes a typical two-level Debian archive,
em(distribution/component). Typically, em(distribution) is one of
em(stable), em(unstable), or em(frozen), while component is one of
em(main), em(contrib), em(non-free), or em(non-us).
The format for a bf(sources.list) entry using the em(deb)
type is:
verb(deb uri distribution [component1] [componenent2] [...])
The URI for the em(deb) type must specify the base of the Debian distribution, 
from which bf(APT) will find the information it needs. em(distribution)
can specify an exact path, in which case the em(component)s
must be omitted and bf(distribution) must end with a slash (/). This is 
useful for when only a particular sub-section of the archive denoted by the 
URI is of interest. If bf(distribution) does not specify an exact path, at 
least one bf(component) must be present.

bf(distribution) may also contain a variable, bf($(ARCH)),
which expands to the Debian architecture (i386, m68k, powerpc, ...)     
used on the system. This permits archiecture-independent                
bf(sources.list) files to be used. In general this is only of interest
when specifying an exact path, bf(APT) will automatically generate a URI
with the current architecture otherwise.

Since only one distribution can be specified per line it may be necessary
to have multiple lines for the same URI, if a subset of all available
distributions or components at that location is desired.
bf(APT) will sort the URI list after it has generated a complete set 
internally, and will collapse multiple references to the same Internet host, 
for instance, into a single connection, so that it does not inefficiently
establish an FTP connection, close it, do something else, and then
re-establish a connection to that same host. This feature is useful
for accessing busy FTP sites with limits on the number of simultaneous
anonymous users. bf(APT) also parallizes connections to different hosts
to more effectively deal with sites with low bandwidth.

It is important to list sources in order of preference, with the most
preferred source listed first. Typically this will result in sorting
by speed from fastest to slowest (CD-ROM followed by hosts on a local
network, followed by distant Internet hosts, for example).

manpagesection(URI specification)
The currently recognized URI types are cdrom, file, http, and ftp.

startdit()
dit(bf(file))
The file scheme allows an arbitrary directory in the file system to be
considered an archive. This is useful for NFS mounts and local mirrors or
archives.

dit(bf(cdrom))
The cdrom scheme allows bf(APT) to use a local CDROM drive with media
swapping. Use the bf(apt-cdrom(8)) program to create cdrom entires in the
source list.

dit(bf(http))
The http scheme specifies an HTTP server for the archive. If an environment
variable bf($http_proxy) is set with the format 
bf(http://server:port/), the proxy server specified in
bf($http_proxy) will be used. Users of authenticated HTTP/1.1 proxies may 
use a string of the format bf(http://user:pass@server:port/)
Note that this is an insecure method of authentication.

dit(bf(ftp))
The ftp scheme specifies an FTP server for the archive. APT's FTP behavior
is highly configurable; for more information see the
bf(apt.conf(5)) manual page.

dit(bf(copy))
The copy scheme is identical to the file scheme except that packages are
copied into the cache directory instead of used directly at their location.
This is usefull for people using a zip disk to copy files around with APT.

enddit()

manpagesection(EXAMPLES)
Uses the archive stored locally (or NFS mounted) at /home/jason/debian
for stable/main, stable/contrib, and stable/non-free.
quote("deb file:/home/jason/debian stable main contrib non-free")

As above, except this uses the unstable (development) distribution.
quote("deb file:/home/jason/debian unstable main contrib non-free")

Uses HTTP to access the archive at www.debian.org, and uses only the
stable/main area.
quote("deb http://www.debian.org/archive stable main")

Uses FTP to access the archive at ftp.debian.org, under the debian
directory, and uses only the stable/contrib area.
quote("deb ftp://ftp.debian.org/debian stable contrib")

Uses FTP to access the archive at ftp.debian.org, under the debian
directory, and uses only the unstable/contrib area. If this line appears as
well as the one in the previous example in bf(sources.list),
a single FTP session will be used for both resource lines.
quote("deb ftp://ftp.debian.org/debian unstable contrib")

Uses FTP to access the archive at nonus.debian.org, under the debian-non-US
directory, and uses only files found under unstable/binary-i386.
quote("deb ftp://nonus.debian.org/debian-non-US unstable/binary-i386/")

Uses HTTP to access the archive at nonus.debian.org, under the
debian-non-US directory, and uses only files found under
unstable/binary-i386 on i386 machines, unstable/binary-m68k on m68k, and so
forth for other supported architectures.
quote("deb http://ftp.de.debian.org/debian-non-US unstable/binary-$(ARCH)/")

manpageseealso()
apt-cache (8),
apt.conf (5)

manpagebugs()
See http://bugs.debian.org/apt.  If you wish to report a
bug in bf(apt-get), please see bf(/usr/doc/debian/bug-reporting.txt)
or the bf(bug(1)) command.

manpageauthor()
apt-get was written by the APT team <apt@packages.debian.org>.