[ previous ] [ Contents ] [ 1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ] [ 7 ] [ 8 ] [ 9 ] [ 10 ] [ 11 ] [ 12 ] [ A ] [ B ] [ C ] [ D ] [ E ] [ F ] [ G ] [ next ]
The location of all files and directories must comply with the Filesystem Hierarchy Standard (FHS), version 2.3, with the exceptions noted below, and except where doing so would violate other terms of Debian Policy. The following exceptions to the FHS apply:
The optional rules related to user specific configuration files for applications are stored in the user's home directory are relaxed. It is recommended that such files start with the '.' character (a "dot file"), and if an application needs to create more than one dot file then the preferred placement is in a subdirectory with a name starting with a '.' character, (a "dot directory"). In this case it is recommended the configuration files not start with the '.' character.
The requirement for amd64 to use /lib64
for 64 bit binaries is
removed.
The requirement for object files, internal binaries, and libraries, including
libc.so.*
, to be located directly under /lib{,32}
and
/usr/lib{,32}
is amended, permitting files to instead be installed
to /lib/triplet
and
/usr/lib/triplet
, where triplet
is the value returned by dpkg-architecture -qDEB_HOST_MULTIARCH
for the architecture of the package. Packages may not install files
to any triplet path other than the one matching the architecture of
that package; for instance, an Architecture: amd64 package
containing 32-bit x86 libraries may not install these libraries to
/usr/lib/i386-linux-gnu
. [69]
Applications may also use a single subdirectory under
/usr/lib/triplet
.
The execution time linker/loader, ld*, must still be made available in the existing location under /lib or /lib64 since this is part of the ELF ABI for the architecture.
The requirement that /usr/local/share/man
be
"synonymous" with /usr/local/man
is relaxed to a
recommendation
The requirement that windowmanagers with a single configuration file call it
system.*wmrc
is removed, as is the restriction that the window
manager subdirectory be named identically to the window manager name itself.
The requirement that boot manager configuration files live in
/etc
, or at least are symlinked there, is relaxed to a
recommendation.
The additional directory /run
in the root file system is allowed.
/run
replaces /var/run
, and the subdirectory
/run/lock
replaces /var/lock
, with the
/var
directories replaced by symlinks for backwards compatibility.
/run
and /run/lock
must follow all of the
requirements in the FHS for /var/run
and /var/lock
,
respectively, such as file naming conventions, file format requirements, or the
requirement that files be cleared during the boot process. Files and
directories residing in /run
should be stored on a temporary file
system.
The following directories in the root filesystem are additionally allowed:
/sys
and /selinux
. [70]
On GNU/Hurd systems, the following additional directories are allowed in the
root filesystem: /hurd
and /servers
.[71]
The version of this document referred here can be found in the
debian-policy package or on FHS (Debian
copy)
alongside this manual (or, if you have the
debian-policy
installed, you can try FHS (local copy)
).
The latest version, which may be a more recent version, may be found on
FHS (upstream)
.
Specific questions about following the standard may be asked on the
debian-devel mailing list, or referred to the FHS mailing list
(see the FHS web site
for more information).
As mandated by the FHS, packages must not place any files in
/usr/local
, either by putting them in the file system archive to
be unpacked by dpkg
or by manipulating them in their maintainer
scripts.
However, the package may create empty directories below /usr/local
so that the system administrator knows where to place site-specific files.
These are not directories in /usr/local
, but are children
of directories in /usr/local
. These directories
(/usr/local/*/dir/
) should be removed on package removal if they
are empty.
Note that this applies only to directories below
/usr/local
, not in /usr/local
. Packages
must not create sub-directories in the directory /usr/local
itself, except those listed in FHS, section 4.5. However, you may create
directories below them as you wish. You must not remove any of the directories
listed in 4.5, even if you created them.
Since /usr/local
can be mounted read-only from a remote server,
these directories must be created and removed by the postinst
and
prerm
maintainer scripts and not be included in the
.deb
archive. These scripts must not fail if either of these
operations fail.
For example, the emacsen-common package could contain something like
if [ ! -e /usr/local/share/emacs ]; then if mkdir /usr/local/share/emacs 2>/dev/null; then if chown root:staff /usr/local/share/emacs; then chmod 2775 /usr/local/share/emacs || true fi fi fi
in its postinst
script, and
rmdir /usr/local/share/emacs/site-lisp 2>/dev/null || true rmdir /usr/local/share/emacs 2>/dev/null || true
in the prerm
script. (Note that this form is used to ensure that
if the script is interrupted, the directory /usr/local/share/emacs
will still be removed.)
If you do create a directory in /usr/local
for local additions to
a package, you should ensure that settings in /usr/local
take
precedence over the equivalents in /usr
.
However, because /usr/local
and its contents are for exclusive use
of the local administrator, a package must not rely on the presence or absence
of files or directories in /usr/local
for normal operation.
The /usr/local
directory itself and all the subdirectories created
by the package should (by default) have permissions 2775 (group-writable and
set-group-id) and be owned by root:staff.
The system-wide mail directory is /var/mail
. This directory is
part of the base system and should not be owned by any particular mail agents.
The use of the old location /var/spool/mail
is deprecated, even
though the spool may still be physically located there.
/run
and /run/lock
The directory /run
is cleared at boot, normally by being a mount
point for a temporary file system. Packages therefore must not assume that any
files or directories under /run
other than /run/lock
exist unless the package has arranged to create those files or directories
since the last reboot. Normally, this is done by the package via an init
script. See Writing the scripts, Section 9.3.2
for more information.
Packages must not include files or directories under /run
, or
under the older /var/run
and /var/lock
paths. The
latter paths will normally be symlinks or other redirections to
/run
for backwards compatibility.
The Debian system can be configured to use either plain or shadow passwords.
Some user ids (UIDs) and group ids (GIDs) are reserved globally for use by certain packages. Because some packages need to include files which are owned by these users or groups, or need the ids compiled into binaries, these ids must be used on any Debian system only for the purpose for which they are allocated. This is a serious restriction, and we should avoid getting in the way of local administration policies. In particular, many sites allocate users and/or local system groups starting at 100.
Apart from this we should have dynamically allocated ids, which should by default be arranged in some sensible order, but the behavior should be configurable.
Packages other than base-passwd must not modify
/etc/passwd
, /etc/shadow
, /etc/group
or
/etc/gshadow
.
The UID and GID numbers are divided into classes as follows:
Globally allocated by the Debian project, the same on every Debian system.
These ids will appear in the passwd
and group
files
of all Debian systems, new ids in this range being added automatically as the
base-passwd package is updated.
Packages which need a single statically allocated uid or gid should use one of these; their maintainers should ask the base-passwd maintainer for ids.
Dynamically allocated system users and groups. Packages which need a user or
group, but can have this user or group allocated dynamically and differently on
each system, should use adduser --system to create the group
and/or user. adduser
will check for the existence of the user or
group, and if necessary choose an unused id based on the ranges specified in
adduser.conf
.
Dynamically allocated user accounts. By default adduser
will
choose UIDs and GIDs for user accounts in this range, though
adduser.conf
may be used to modify this behavior.
Globally allocated by the Debian project, but only created on demand. The ids are allocated centrally and statically, but the actual accounts are only created on users' systems on demand.
These ids are for packages which are obscure or which require many
statically-allocated ids. These packages should check for and create the
accounts in /etc/passwd
or /etc/group
(using
adduser
if it has this facility) if necessary. Packages which are
likely to require further allocations should have a "hole" left after
them in the allocation, to give them room to grow.
Reserved.
User nobody. The corresponding gid refers to the group nogroup.
(uid_t)(-1) == (gid_t)(-1) must not be used, because it is the error return sentinel value.
init.d
scripts
The /etc/init.d
directory contains the scripts executed by
init
at boot time and when the init state (or
"runlevel") is changed (see init(8)
).
There are at least two different, yet functionally equivalent, ways of handling
these scripts. For the sake of simplicity, this document describes only the
symbolic link method. However, it must not be assumed by maintainer scripts
that this method is being used, and any automated manipulation of the various
runlevel behaviors by maintainer scripts must be performed using
update-rc.d
as described below and not by manually installing or
removing symlinks. For information on the implementation details of the other
method, implemented in the file-rc package, please refer to the
documentation of that package.
These scripts are referenced by symbolic links in the
/etc/rcn.d
directories. When changing runlevels,
init
looks in the directory /etc/rcn.d
for
the scripts it should execute, where n is the runlevel
that is being changed to, or S for the boot-up scripts.
The names of the links all have the form
Smmscript
or
Kmmscript
where mm is a two-digit
number and script is the name of the script (this should be the same
as the name of the actual script in /etc/init.d
).
When init
changes runlevel first the targets of the links whose
names start with a K are executed, each with the single argument
stop, followed by the scripts prefixed with an S,
each with the single argument start. (The links are those in the
/etc/rcn.d
directory corresponding to the new
runlevel.) The K links are responsible for killing services and
the S link for starting services upon entering the runlevel.
For example, if we are changing from runlevel 2 to runlevel 3, init will first
execute all of the K prefixed scripts it finds in
/etc/rc3.d
, and then all of the S prefixed scripts in
that directory. The links starting with K will cause the
referred-to file to be executed with an argument of stop, and the
S links with an argument of start.
The two-digit number mm is used to determine the order in which to
run the scripts: low-numbered links have their scripts run first. For example,
the K20 scripts will be executed before the K30
scripts. This is used when a certain service must be started before another.
For example, the name server bind
might need to be started before
the news server inn
so that inn
can set up its access
lists. In this case, the script that starts bind
would have a
lower number than the script that starts inn
so that it runs
first:
/etc/rc2.d/S17bind /etc/rc2.d/S70inn
The two runlevels 0 (halt) and 6 (reboot) are slightly different. In these runlevels, the links with an S prefix are still called after those with a K prefix, but they too are called with the single argument stop.
Packages that include daemons for system services should place scripts in
/etc/init.d
to start or stop services at boot time or during a
change of runlevel. These scripts should be named
/etc/init.d/package
, and they should accept one
argument, saying what to do:
start the service,
stop the service,
stop and restart the service if it's already running, otherwise start the service
cause the configuration of the service to be reloaded without actually stopping and restarting the service,
cause the configuration to be reloaded if the service supports this, otherwise restart the service.
The start, stop, restart, and
force-reload options should be supported by all scripts in
/etc/init.d
, the reload option is optional.
The init.d
scripts must ensure that they will behave sensibly
(i.e., returning success and not starting multiple copies of a service) if
invoked with start when the service is already running, or with
stop when it isn't, and that they don't kill unfortunately-named
user processes. The best way to achieve this is usually to use
start-stop-daemon
with the --oknodo option.
Be careful of using set -e in init.d
scripts.
Writing correct init.d
scripts requires accepting various error
exit statuses when daemons are already running or already stopped without
aborting the init.d
script, and common init.d
function libraries are not safe to call with set -e in effect[72]. For init.d
scripts, it's often easier to not use set -e and instead check the
result of each command separately.
If a service reloads its configuration automatically (as in the case of
cron
, for example), the reload option of the
init.d
script should behave as if the configuration has been
reloaded successfully.
The /etc/init.d
scripts must be treated as configuration files,
either (if they are present in the package, that is, in the .deb file) by
marking them as conffiles, or, (if they do not exist in the .deb)
by managing them correctly in the maintainer scripts (see Configuration files, Section 10.7).
This is important since we want to give the local system administrator the
chance to adapt the scripts to the local system, e.g., to disable a service
without de-installing the package, or to specify some special command line
options when starting a service, while making sure their changes aren't lost
during the next package upgrade.
These scripts should not fail obscurely when the configuration files remain but
the package has been removed, as configuration files remain on the system after
the package has been removed. Only when dpkg
is executed with the
--purge option will configuration files be removed. In
particular, as the /etc/init.d/package
script itself is
usually a conffile, it will remain on the system if the package is
removed but not purged. Therefore, you should include a test
statement at the top of the script, like this:
test -f program-executed-later-in-script || exit 0
Often there are some variables in the init.d
scripts whose values
control the behavior of the scripts, and which a system administrator is likely
to want to change. As the scripts themselves are frequently
conffiles, modifying them requires that the administrator merge in
their changes each time the package is upgraded and the conffile
changes. To ease the burden on the system administrator, such configurable
values should not be placed directly in the script. Instead, they should be
placed in a file in /etc/default
, which typically will have the
same base name as the init.d
script. This extra file should be
sourced by the script when the script runs. It must contain only variable
settings and comments in SUSv3 sh
format. It may either be a
conffile or a configuration file maintained by the package
maintainer scripts. See Configuration
files, Section 10.7 for more details.
To ensure that vital configurable values are always available, the
init.d
script should set default values for each of the shell
variables it uses, either before sourcing the /etc/default/
file
or afterwards using something like the : ${VAR:=default} syntax.
Also, the init.d
script must behave sensibly and not fail if the
/etc/default
file is deleted.
Files and directories under /run
, including ones referred to via
the compatibility paths /var/run
and /var/lock
, are
normally stored on a temporary filesystem and are normally not persistent
across a reboot. The init.d
scripts must handle this correctly.
This will typically mean creating any required subdirectories dynamically when
the init.d
script is run. See /run
and /run/lock
, Section
9.1.4 for more information.
Maintainers should use the abstraction layer provided by the
update-rc.d
and invoke-rc.d
programs to deal with
initscripts in their packages' scripts such as postinst
,
prerm
and postrm
.
Directly managing the /etc/rc?.d links and directly invoking the
/etc/init.d/
initscripts should be done only by packages providing
the initscript subsystem (such as sysv-rc
and
file-rc
).
The program update-rc.d
is provided for package maintainers to
arrange for the proper creation and removal of
/etc/rcn.d
symbolic links, or their functional
equivalent if another method is being used. This may be used by maintainers in
their packages' postinst
and postrm
scripts.
You must not include any /etc/rcn.d
symbolic links in
the actual archive or manually create or remove the symbolic links in
maintainer scripts; you must use the update-rc.d
program instead.
(The former will fail if an alternative method of maintaining runlevel
information is being used.) You must not include the
/etc/rcn.d
directories themselves in the archive
either. (Only the sysvinit package may do so.)
By default update-rc.d
will start services in each of the
multi-user state runlevels (2, 3, 4, and 5) and stop them in the halt runlevel
(0), the single-user runlevel (1) and the reboot runlevel (6). The system
administrator will have the opportunity to customize runlevels by simply
adding, moving, or removing the symbolic links in
/etc/rcn.d
if symbolic links are being used, or by
modifying /etc/runlevel.conf
if the file-rc method is
being used.
To get the default behavior for your package, put in your postinst
script
update-rc.d package defaults
and in your postrm
if [ "$1" = purge ]; then update-rc.d package remove fi
. Note that if your package changes runlevels or priority, you may have to
remove and recreate the links, since otherwise the old links may persist.
Refer to the documentation of update-rc.d
.
This will use a default sequence number of 20. If it does not matter when or
in which order the init.d
script is run, use this default. If it
does, then you should talk to the maintainer of the sysvinit
package or post to debian-devel, and they will help you choose a
number.
For more information about using update-rc.d, please consult its
man page update-rc.d(8)
.
The program invoke-rc.d
is provided to make it easier for package
maintainers to properly invoke an initscript, obeying runlevel and other
locally-defined constraints that might limit a package's right to start, stop
and otherwise manage services. This program may be used by maintainers in
their packages' scripts.
The package maintainer scripts must use invoke-rc.d
to invoke the
/etc/init.d/*
initscripts, instead of calling them directly.
By default, invoke-rc.d
will pass any action requests (start,
stop, reload, restart...) to the /etc/init.d
script, filtering out
requests to start or restart a service out of its intended runlevels.
Most packages will simply need to change:
/etc/init.d/<package> <action>
in their postinst
and prerm
scripts to:
if which invoke-rc.d >/dev/null 2>&1; then invoke-rc.d package <action> else /etc/init.d/package <action> fi
A package should register its initscript services using
update-rc.d
before it tries to invoke them using
invoke-rc.d
. Invocation of unregistered services may fail.
For more information about using invoke-rc.d
, please consult its
man page invoke-rc.d(8)
.
There used to be another directory, /etc/rc.boot
, which contained
scripts which were run once per machine boot. This has been deprecated in
favour of links from /etc/rcS.d
to files in
/etc/init.d
as described in Introduction,
Section 9.3.1. Packages must not place files in /etc/rc.boot
.
An example on which you can base your /etc/init.d
scripts is found
in /etc/init.d/skeleton
.
init.d
scripts
This section describes the formats to be used for messages written to standard
output by the /etc/init.d
scripts. The intent is to improve the
consistency of Debian's startup and shutdown look and feel. For this reason,
please look very carefully at the details. We want the messages to have the
same format in terms of wording, spaces, punctuation and case of letters.
Here is a list of overall rules that should be used for messages generated by
/etc/init.d
scripts.
The message should fit in one line (fewer than 80 characters), start with a capital letter and end with a period (.) and line feed ("\n").
If the script is performing some time consuming task in the background (not merely starting or stopping a program, for instance), an ellipsis (three dots: ...) should be output to the screen, with no leading or tailing whitespace or line feeds.
The messages should appear as if the computer is telling the user what it is doing (politely :-), but should not mention "it" directly. For example, instead of:
I'm starting network daemons: nfsd mountd.
the message should say
Starting network daemons: nfsd mountd.
init.d script should use the following standard message formats for the situations enumerated below.
When daemons are started
If the script starts one or more daemons, the output should look like this (a single line, no leading spaces):
Starting description: daemon-1 ... daemon-n.
The description should describe the subsystem the daemon or set of daemons are part of, while daemon-1 up to daemon-n denote each daemon's name (typically the file name of the program).
For example, the output of /etc/init.d/lpd
would look like:
Starting printer spooler: lpd.
This can be achieved by saying
echo -n "Starting printer spooler: lpd" start-stop-daemon --start --quiet --exec /usr/sbin/lpd echo "."
in the script. If there are more than one daemon to start, the output should look like this:
echo -n "Starting remote file system services:" echo -n " nfsd"; start-stop-daemon --start --quiet nfsd echo -n " mountd"; start-stop-daemon --start --quiet mountd echo -n " ugidd"; start-stop-daemon --start --quiet ugidd echo "."
This makes it possible for the user to see what is happening and when the final daemon has been started. Care should be taken in the placement of white spaces: in the example above the system administrators can easily comment out a line if they don't want to start a specific daemon, while the displayed message still looks good.
When a system parameter is being set
If you have to set up different system parameters during the system boot, you should use this format:
Setting parameter to "value".
You can use a statement such as the following to get the quotes right:
echo "Setting DNS domainname to \"$domainname\"."
Note that the same symbol (") is used for the left and right quotation marks. A grave accent (`) is not a quote character; neither is an apostrophe (').
When a daemon is stopped or restarted
When you stop or restart a daemon, you should issue a message identical to the startup message, except that Starting is replaced with Stopping or Restarting respectively.
For example, stopping the printer daemon will look like this:
Stopping printer spooler: lpd.
When something is executed
There are several examples where you have to run a program at system startup or
shutdown to perform a specific task, for example, setting the system's clock
using netdate
or killing all processes when the system shuts down.
Your message should look like this:
Doing something very useful...done.
You should print the done. immediately after the job has been completed, so that the user is informed why they have to wait. You can get this behavior by saying
echo -n "Doing something very useful..." do_something echo "done."
in your script.
When the configuration is reloaded
When a daemon is forced to reload its configuration files you should use the following format:
Reloading description configuration...done.
where description is the same as in the daemon starting message.
Packages must not modify the configuration file /etc/crontab
, and
they must not modify the files in /var/spool/cron/crontabs
.
If a package wants to install a job that has to be executed via cron, it should place a file named as specified in Cron job file names, Section 9.5.1 into one or more of the following directories:
/etc/cron.hourly /etc/cron.daily /etc/cron.weekly /etc/cron.monthly
As these directory names imply, the files within them are executed on an
hourly, daily, weekly, or monthly basis, respectively. The exact times are
listed in /etc/crontab
.
All files installed in any of these directories must be scripts (e.g., shell scripts or Perl scripts) so that they can easily be modified by the local system administrator. In addition, they must be treated as configuration files.
If a certain job has to be executed at some other frequency or at a specific
time, the package should install a file in /etc/cron.d
with a name
as specified in Cron job file names, Section 9.5.1.
This file uses the same syntax as /etc/crontab
and is processed by
cron
automatically. The file must also be treated as a
configuration file. (Note that entries in the /etc/cron.d
directory are not handled by anacron
. Thus, you should only use
this directory for jobs which may be skipped if the system is not running.)
Unlike crontab
files described in the IEEE Std 1003.1-2008
(POSIX.1) available from The Open
Group
, the files in /etc/cron.d
and the file
/etc/crontab
have seven fields; namely:
Minute [0,59]
Hour [0,23]
Day of the month [1,31]
Month of the year [1,12]
Day of the week ([0,6] with 0=Sunday)
Username
Command to be run
Ranges of numbers are allowed. Ranges are two numbers separated with a hyphen. The specified range is inclusive. Lists are allowed. A list is a set of numbers (or ranges) separated by commas. Step values can be used in conjunction with ranges.
The scripts or crontab entries in these directories should check if all necessary programs are installed before they try to execute them. Otherwise, problems will arise when a package was removed but not purged since configuration files are kept on the system in this situation.
Any cron daemon must provide /usr/bin/crontab
and
support normal crontab entries as specified in POSIX. The daemon
must also support names for days and months, ranges, and step values. It has
to support /etc/crontab
, and correctly execute the scripts in
/etc/cron.d
. The daemon must also correctly execute scripts in
/etc/cron.{hourly,daily,weekly,monthly}
.
The file name of a cron job file should normally match the name of the package from which it comes.
If a package supplies multiple cron job files files in the same directory, the file names should all start with the name of the package (possibly modified as described below) followed by a hyphen (-) and a suitable suffix.
A cron job file name must not include any period or plus characters (. or +) characters as this will cause cron to ignore the file. Underscores (_) should be used instead of . and + characters.
The Debian menu package provides a standard interface between
packages providing applications and menu programs (either X window
managers or text-based menu programs such as pdmenu
).
All packages that provide applications that need not be passed any special command line arguments for normal operation should register a menu entry for those applications, so that users of the menu package will automatically get menu entries in their window managers, as well in shells like pdmenu.
Menu entries should follow the current menu policy.
The menu policy can be found in the menu-policy files in the
debian-policy package. It is also available from the Debian web
mirrors at /doc/packaging-manuals/menu-policy/
.
Please also refer to the Debian Menu System documentation that comes
with the menu
package for information about how to register your
applications.
MIME (Multipurpose Internet Mail Extensions, RFCs 2045-2049) is a mechanism for encoding files and data streams and providing meta-information about them, in particular their type (e.g. audio or video) and format (e.g. PNG, HTML, MP3).
Registration of MIME type handlers allows programs like mail user agents and web browsers to invoke these handlers to view, edit or display MIME types they don't support directly.
Packages which provide the ability to view/show/play, compose, edit or print MIME types should register themselves as such following the current MIME support policy.
The mime-support
package provides the update-mime
program which allows packages to register programs that can show, compose, edit
or print MIME types.
Packages containing such programs must register them with
update-mime
as documented in update-mime(8)
. They
should not depend on, recommend, or suggest mime-support
.
Instead, they should just put something like the following in the
postinst and postrm scripts:
if [ -x /usr/sbin/update-mime ]; then update-mime fi
To achieve a consistent keyboard configuration so that all applications interpret a keyboard event the same way, all programs in the Debian distribution must be configured to comply with the following guidelines.
The following keys must have the specified interpretations:
delete the character to the left of the cursor
delete the character to the right of the cursor
emacs: the help prefix
The interpretation of any keyboard events should be independent of the terminal that is used, be it a virtual console, an X terminal emulator, an rlogin/telnet session, etc.
The following list explains how the different programs should be set up to achieve this:
<-- generates KB_BackSpace in X.
Delete generates KB_Delete in X.
X translations are set up to make KB_Backspace generate ASCII DEL,
and to make KB_Delete generate ESC [ 3 ~ (this is the
vt220 escape code for the "delete character" key). This must be done
by loading the X resources using xrdb
on all local X displays, not
using the application defaults, so that the translation resources used
correspond to the xmodmap
settings.
The Linux console is configured to make <-- generate DEL, and Delete generate ESC [ 3 ~.
X applications are configured so that < deletes left, and Delete deletes right. Motif applications already work like this.
Terminals should have stty erase ^? .
The xterm terminfo entry should have ESC [ 3 ~ for kdch1, just as for TERM=linux and TERM=vt220.
Emacs is programmed to map KB_Backspace or the stty erase character to delete-backward-char, and KB_Delete or kdch1 to delete-forward-char, and ^H to help as always.
Other applications use the stty erase character and kdch1 for the two delete keys, with ASCII DEL being "delete previous character" and kdch1 being "delete character under cursor".
This will solve the problem except for the following cases:
Some terminals have a <-- key that cannot be made to produce anything except ^H. On these terminals Emacs help will be unavailable on ^H (assuming that the stty erase character takes precedence in Emacs, and has been set correctly). M-x help or F1 (if available) can be used instead.
Some operating systems use ^H for stty erase. However, modern telnet versions and all rlogin versions propagate stty settings, and almost all UNIX versions honour stty erase. Where the stty settings are not propagated correctly, things can be made to work by using stty manually.
Some systems (including previous Debian versions) use xmodmap
to
arrange for both <-- and Delete to generate
KB_Delete. We can change the behavior of their X clients using
the same X resources that we use to do it for our own clients, or configure our
clients using their resources when things are the other way around. On
displays configured like this Delete will not work, but
<-- will.
Some operating systems have different kdch1 settings in their terminfo database for xterm and others. On these systems the Delete key will not work correctly when you log in from a system conforming to our policy, but <-- will.
A program must not depend on environment variables to get reasonable defaults.
(That's because these environment variables would have to be set in a
system-wide configuration file like /etc/profile
, which is not
supported by all shells.)
If a program usually depends on environment variables for its configuration, the program should be changed to fall back to a reasonable default configuration if these environment variables are not present. If this cannot be done easily (e.g., if the source code of a non-free program is not available), the program must be replaced by a small "wrapper" shell script which sets the environment variables if they are not already defined, and calls the original program.
Here is an example of a wrapper script for this purpose:
#!/bin/sh BAR=${BAR:-/var/lib/fubar} export BAR exec /usr/lib/foo/foo "$@"
Furthermore, as /etc/profile
is a configuration file of the
base-files
package, other packages must not put any environment
variables or other commands into that file.
The doc-base
package implements a flexible mechanism for handling
and presenting documentation. The recommended practice is for every Debian
package that provides online documentation (other than just manual pages) to
register these documents with doc-base
by installing a
doc-base
control file in /usr/share/doc-base/
.
Please refer to the documentation that comes with the doc-base
package for information and details.
[ previous ] [ Contents ] [ 1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ] [ 7 ] [ 8 ] [ 9 ] [ 10 ] [ 11 ] [ 12 ] [ A ] [ B ] [ C ] [ D ] [ E ] [ F ] [ G ] [ next ]
Debian Policy Manual
version 3.9.3.1, 2012-03-13