once again, an email I will keep & refer to...
I hear you loud & clear:-)
Thank you for taking the time to explain this... Very useful.
Cheers,
Jean-Claude Provost
On 8/17/2016 5:17 PM, Jeffery Mewtamer wrote:
Debian(of which Raspbian is an optimized for the Pi release of) is
fairly conservative in pushing out package updates, so Stable tends to
be rock solid, and even Testing is often more stable than many distros
that value bleeding edge over stability.
That said, if you want to try installing a newer version from
Testing(jessie is the current stable release), the config file you
want is /etc/apt/sources.list.
in this file, you should find one or more lines of the following form:
deb http://ftp.us.debian.org/debian testing main
this line has four components, in order from left to right, they are:
1. deb for binary package repositories or deb-src for source code
repositories.
2. the URL of the repository. the us in the URL from the example may
be replaced with the two letter code of your home country if you live
outside of America.
3. The release. The example here uses testing, but the jessie image is
likely to have jessie or stable in this spot. releases can be
designated by branch(oldstable, stable, testing, unstable) or
codename(wheezy, jessie, stretch, sid).
4. license. The example line only includes main, but your sources.list
might have main contrib non-free here.
if you want to completely switch over to testing, you can simply
replace every instance of jessie or stable with stretch or testing.
Some consider using the codenames to be more stable in the longrun as
you'll stay with the named release when the next stable release comes
out(i.e. if you have jessie in your sources.list, you'll stay with
jessie when it becomes oldstable, but if you use stable, you'll
automatically be upgrade from jessie to stretch when stretch becomes
stable).
If you just want specific packages upgraded to their testing version,
you can add new lines to your sources.list and the line
APT::Default-Release "stable";
to /etc/apt/apt.conf
which will cause packages installed from stable to only be upgraded
when a new version is added to the stable repository and only packages
installed from testing will be upgraded when testing gets a new
version.
I haven't used brltty before, so I can't help you with that, but I'm
running my desktop off tDebian Testing's repository and can tell you
the version in testing is currently 5.3.
If the newest version has a .deb available for download from their
website, you can use dpkg to install it manually, though dpkg will
fail if you are missing any dependencies.
In general, I'd say installing a newer version of a specific package
is fairly low risk provided none of it's dependencies overlap with a
package that isn't being upgraded*, but I would still say it's
recommended that those new to debian based system stick with the
versions available in stable.
*One way this can cause problems is as follows:
PackageA and PackageB both depend on PackageC.
You currently have version 1.0 of each installed.
You want to upgrade PackageA to 2.0 while keeping PackageB at 1.0.
PackageA 2.0 requires upgrading PackageC to 2.0, but PackageB 1.0
requires keeping PackageC at 1.0, and you can't have two versions of
PackageC installed at the same time.
Generally, if something like this happens in Aptitude, it's
suggestions will usually include:
Upgrade all three.
Keep all three at their current version.
Remove either A or B.
