Newsgroups:  gmane.linux.debian.user
Date:        Sat, 29 Jan 2005 11:41:18 +0000 (UTC)

> Linux-PAM sysadmin guide, in /usr/share/doc/libpam-doc/ in the section
> "Set/unset environment variables".

That s a good start.

But no there is no debian documentation/policy about environment/profile. In fact there is a "war" between maintenair about who set what (only for the PATH variable as far as i know). Thus you cannot set the PATH var in /etc/environment and expect it to be used by all apps (shells, cron dameon, gdm , … overwrite it all the time).

/etc/environment is used by all applications. It is not a shell script (not like /etc/profile where you can use export, alias, etc). You can only set key pair values like:

LANG=fr_FR.UTF-8@euro
NNTPSERVER=localhost

If your application use pam check that its /etc/pam.d script have a pam_env rule:

/etc/pam.d/ssh

# PAM configuration for the Secure Shell service

# Read environment variables from /etc/environment and
# /etc/security/pam_env.conf.
auth       required     pam_env.so # [1]

# Standard Un*x authentication.
@include common-auth

# Standard Un*x authorization.
@include common-account

# Standard Un*x session setup and teardown.
@include common-session

# Print the message of the day upon successful login.
session    optional     pam_motd.so # [1]

# Print the status of the user's mailbox upon successful login.
session    optional     pam_mail.so standard noenv # [1]

# Set up user limits from /etc/security/limits.conf.
session    required     pam_limits.so

# Standard Un*x password updating.
@include common-password

As told there the pam_env module not only export the variables you setted in /etc/security/pam_env.conf but also those in /etc/environment. All applications are supposed to read /etc/environment anyway. http://publib.boulder.ibm.com/infocenter/pseries/topic/com.ibm.aix.doc/fil es/aixfiles/environment.htm gives an idea of how things work on unix. as i told the PATH part is wrong on debian.

A few real examples:

To sum up /etc/environment is great to set variables like the news server, the proxy and other things that no scripts used to care about. For lang and things like JAVA_HOME, you should clean all your bash specific tweaks in /etc/profile to be able to change the setting from /etc/environment and forget about it.

For PATH it is useless, every daemon/shell/X11 login manager redefine PATH afterwards. (i am looking after the day when a pam_path session module will exists !)

The last thing is that its a standard for all unix applications. There is no other file for that.

Alban Browaeys