Throughout this chapter there have been mentions of the environment,
such as environmental variables.
For instance it was shown that the environmental variable
$PROMPT allowed the user to change the appearance of his prompt
during an interactive session.
What if however, a user would like to have that prompt setting as the
default for every session?
As was mentioned earlier, the prompt setting can be placed in a file
.profile in his home directory which is executed at each
This file is simply a script that the shell looks for at login and
will execute at that time.
This is where any enviromental variables should be set, such as
There will likely be a file
/etc/profile which will also
execute during login.
This is a file that the system administrator will have set as a
default so that users do not need a
.profile in their own
It also allows the system administrator to set some things like the
path so that the users on the system can have access to all of the
executables without having to try and figure out the paths for them.
Depending on the user's level of access, the
often a good file to copy into his directory as a skeleton to start
As well as enviromental settings, function definitions can also be
placed in this file.
This means that the
list function which was described in the
section on functions can be used during every session without having
to be re-entered.
It is always good practice to keep the functions in their own file to
prevent cluttering up the
As will be seen in later chapters, the newer shells can have several
of these startup files which can be quite confusing if not organized
in some fashion.
The functions can all be put into a file called
which would then be executed by the
.function file can be executed using the
command or the
.profile script would then have one of the following two
lines (which are equivalent):