path: root/erts/doc/src/werl.xml

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<comref>
  <header>
    <copyright>
      <year>1998</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.
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    </legalnotice>

    <title>werl</title>
    <prepared>Bj&ouml;rn Gustavsson</prepared>
    <responsible>Bjarne D&auml;cker</responsible>
    <docno>1</docno>
    <approved>Bjarne D&auml;cker</approved>
    <checked></checked>
    <date>1998-01-26</date>
    <rev>A</rev>
    <file>werl.xml</file>
  </header>
  <com>werl</com>
  <comsummary>The Erlang Emulator</comsummary>
  <description>
    <p>On Windows, the preferred way to start the Erlang system for interactive
      use is as follows:</p>

    <p><c><![CDATA[werl <arguments>]]></c></p>

    <p>This starts Erlang in its own window, with fully
      functioning command-line editing and scrollbars. All flags
      except <c><![CDATA[-oldshell]]></c> work as they do for
      command <seealso marker="erl"><c>erl</c></seealso>.</p>

    <list type="bulleted">
      <item>
        <p>To copy text to the clipboard, use <c>Ctrl-C</c>.</p>
      </item>
      <item>
        <p>To paste text, use <c>Ctrl-V</c>.</p>
      </item>
      <item>
        <p>To interrupt the runtime system or the shell process (depending
          on what has been specified with system flag <c>+B</c>), use
          <c>Ctrl-Break</c>.</p>
      </item>
    </list>

    <p>In cases where you want to redirect standard input and/or
      standard output or use Erlang in a pipeline, <c>werl</c> is
      not suitable, and the <c>erl</c> program is to be used instead.</p>
    
    <p>The <c>werl</c> window is in many ways modeled after the <c>xterm</c>
      window present on other platforms, as the <c>xterm</c> model
      fits well with line-oriented command-based interaction. This
      means that selecting text is line-oriented rather than
      rectangle-oriented.</p>

    <list type="bulleted">
      <item>
        <p>To select text in the <c>werl</c> window, press and hold
          the left mouse button and drag the mouse over the text you want
          to select. If the selection crosses line boundaries, the
          selected text consists of complete lines where applicable
          (just like in a word processor).</p>
      </item>
      <item>
        <p>To select more text than fits
          in the window, start by selecting a small part in the
          beginning of the text you want, then use the scrollbar
          to view the end of the desired selection, point to it, and press
          the <em>right</em> mouse button. The whole area between your
          first selection and the point where you right-clicked is
          included in the selection.</p>
      </item>
      <item>
        <p>To copy the selected text to the clipboard, either
          use <c>Ctrl-C</c>, use the menu, or press the copy
          button in the toolbar.</p>
      </item>
    </list>

    <p>Pasted text is inserted at the current prompt position
      and is interpreted by Erlang as usual keyboard input.</p>

    <list type="bulleted">
      <item>
        <p>To retrieve previous command lines, press the <c>Up arrow</c> or
          use <c>Ctrl-P</c>.</p>
      </item>
    </list>
      
    <p>A drop-down box in the toolbar contains the command
      history. Selecting a command in the drop-down box inserts the command
      at the prompt, as if you used the keyboard to retrieve the
      command.</p>

    <list type="bulleted">
      <item>
        <p>To stop the Erlang emulator, close the <c>werl</c> window.</p>
      </item>
    </list>
  </description>
</comref>