path: root/lib/stdlib/doc/src/shell_default.xml

<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE erlref SYSTEM "erlref.dtd">

<erlref>
  <header>
    <copyright>
      <year>1996</year>
      <year>2016</year>
      <holder>Ericsson AB, All Rights Reserved</holder>
    </copyright>
    <legalnotice>
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
 
      http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

  The Initial Developer of the Original Code is Ericsson AB.
    </legalnotice>

    <title>shell_default</title>
    <prepared>Joe Armstrong</prepared>
    <responsible>Joe Armstrong</responsible>
    <docno></docno>
    <approved>Bjarne D&auml;cker</approved>
    <checked>Joe Armstrong</checked>
    <date>1996-09-09</date>
    <rev>A</rev>
    <file>shell_default.xml</file>
  </header>
  <module>shell_default</module>
  <modulesummary>Customizing the Erlang environment.</modulesummary>
  <description>
    <p>The functions in this module are called when no module name is
      specified in a shell command.</p>

    <p>Consider the following shell dialog:</p>

    <pre>
1> <input>lists:reverse("abc").</input>
"cba"
2> <input>c(foo).</input>
{ok, foo}</pre>

    <p>In command one, module <seealso marker="lists"><c>lists</c></seealso> is
      called. In command two, no module name is specified. The shell searches
      module <c>user_default</c> followed by module <c>shell_default</c> for
      function <c>foo/1</c>.</p>

    <p><c>shell_default</c> is intended for "system wide"
      customizations to the shell. <c>user_default</c> is intended for
      "local" or individual user customizations.</p>
  </description>

  <section>
    <title>Hint</title>
    <p>To add your own commands to the shell, create a module called
      <c>user_default</c> and add the commands you want. Then add the
      following line as the <em>first</em> line in your <c>.erlang</c> file in
      your home directory.</p>

    <pre>
code:load_abs("$PATH/user_default").</pre>

    <p><c>$PATH</c> is the directory where your
      <c>user_default</c> module can be found.</p>
  </section>
</erlref>