The functions in shell_default are called when no module
name is given in a shell command.
Consider the following shell dialogue:
1 > lists:reverse("abc").
"cba"
2 > c(foo).
{ok, foo}
In command one, the module lists is called. In command
two, no module name is specified. The shell searches the modules
user_default followed by shell_default for the
function foo/1.
shell_default is intended for "system wide"
customizations to the shell. user-default is intended for
"local" or individual user customizations.
To add your own commands to the shell, create a module called
user_default and add the commands you want. Then add the
following line as the first line in your .erlang file in your
home directory.
code:load_abs("$PATH/user_default").
$PATH is the directory where your
user_default module can be found.