2 - Raspberry PI Community Projects

GOING FURTHER
Auto-mounting
The am-utils package provides the amd auto-mounting utility, able to mount
removable media on demand when a user aempts to access their usual mount
point. It will unmount these devices when no process is accessing them any
longer.
Other auto-mounting utilities exist, such as automount in the autofs package.
Note also that GNOME, KDE, and other graphical desktop environments work
together with the hal (Hardware Abstraction Layer) system, and can automatically
mount removable media when they are connected.
8.9.6. locate and updatedb
The locate command can find the location of a file when you only know part of the name. It
sends a result almost instantaneously, since it consults a database that stores the location of all
the files on the system; this database is updated daily by the updatedb command (executed by
the /etc/cron.daily/find script).
Since anybody can use locate, it is important to ensure hidden files are not revealed to the user.
This is why the updatedb command runs with the limited permission of the nobody user, which
is a classic pattern on Unix systems for this kind of task. Furthermore, the administrator can
configure some directories to be skipped by simply listing them in the PRUNEDPATHS variable in
/etc/updatedb.conf.
The slocate package goes even further, by replacing the locate command with a more secure
version that only returns the names of files accessible to the user who employs it.
8.10. Compiling a Kernel
The kernels provided by Debian include the largest possible number of features, as well as the
maximum of drivers, in order to cover the broadest spectrum of existing hardware configurations.
This is why some users prefer to recompile the kernel in order to only include what they
specifically need. There are two reasons for this choice. First, it may be to optimize memory
consumption, since the kernel code, even if it is never used, occupies memory for nothing (and
never “goes down” on the swap space, since it is actual RAM that it uses), which can decrease
overall system performance. A locally compiled kernel can also limit the risk of security problems
since only a fraction of the kernel code is compiled and run.
NOTE
Security updates
If you choose to compile your own kernel, you must accept the consequences:
Debian can not ensure security updates for your custom kernel. By keeping
the kernel provided by Debian, you benefit from updates prepared by the Debian
Project's security team.
Recompilation of the kernel is also necessary if you want to use certain features that are only
available as patches (and not included in the standard kernel version).
Chapter 8 — Basic Configuration: Network, Accounts, Printing…
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