;;;-*- Fonts: cthl12, cthl12i, cthl12b, cptfontb, hl10, ct18b, cthl12b, cthl12b, cthl12b, brchars -*-  document browser THE COMPUTER * THOUGHT DOCUMENTATION BROWSER RELEASE 1.0 DOCUMENT NO. 3004 SEPTEMBER 26, 1984 Computer * Thought Corporation 1721 West Plano Parkway Suite 125 Plano, Texas 75075 214-424-3511 Copyright (C) 1984 Computer * Thought Corporation NOTICE The software product described herein is the sole and exclusive property of Computer * Thought Corporation. All rights to its use are conditioned upon and granted pursuant to an executed Non-Exclusive System License Agreement (the "Agreement"). The distribution of the software product described herein is intended for the use of the original licensee only and for use on the computer system specified in the Agreement. Lawful users of the software product are licensed only to read the program from its medium into the memory of the specified computer solely for the purpose of executing the program. Copying, duplicating, selling, or otherwise distributing the software product or this operating manual, in whole or in part, in any media is a violation of the law and of the terms and conditions of the Agreement. DISCLAIMER Computer * Thought Corporation makes no representation or warranties with respect to the contents hereof or with respect to the software product described herein and specifically disclaims any implied warranties of merchantability, fitness for any particular purpose, that use of the software product will not infringe any patent, copyright or trademark, or otherwise. Further, Computer * Thought Corporation reserves the right to revise the software product and this operating manual and to make changes from time to time in the content hereof without obligation of Computer * Thought Corporation to notify any person or organization of such revision or changes except as provided in the Agreement. Computer * Thought Corporation shall not be liable for technical or editorial omissions made herein; nor for incidental or consequential damages resulting from the furnishing, performance or use of the software product or this material. Copyright [copyright] 1984 by Computer * Thought Corporation. All rights reserved worldwide.  chapter br-chapter-1 51. Introduction 0 The Computer * Thought Browser is an on-line documentation system that gives you screen access to documents like the 1Computer * Thought Interpreter/Debugger User Manual0 or the 1Ada Language Reference Manual0 without the need to refer to the hardcopy manuals themselves. If, for example, you are debugging an Ada program using the Interactive Debugger, you can quickly access one of these manuals from your Lisp Machine workstation. The documents as they appear on-line are very similar to the way they look on paper, with a few exceptions. Figures cannot be shown on-screen, although references to hardcopy figures remain in the text. Instead of page numbering, a system of progressive menus is used to locate chapters, sections and subsections. You can review the manual's table of contents, then use your mouse (pointing device) to select one of the chapters. Once you select a chapter, a submenu appears allowing you to scroll through that chapter from the beginning or select a section from within the chapter. When you select a section, you are then given the opportunity to select a subsection. The Browser allows you to make all your selections and do all your scrolling using your mouse, without ever requiring you to use the keyboard. The remainder of this manual gives you the particulars on how to use the Browser. Chapter 3 gives instructions for invoking the Browser from your Lisp Machine. Once you are in the Browser, you can access this manual on-line by selecting it from one of several menus. Figure 1-1 shows one way you might begin this selection, and Figure 1-2 shows how the chapter you are reading right now would appear on-line using the Browser. In subsequent chapters, you will learn more specific procedures for choosing and viewing text. Figure 1-1: Selecting This Manual in the Browser Figure 1-2: How The Chapter You Are Reading Looks On-Screen  chapter br-chapter-2 52. Document Conventions 0 The following conventions are used in this manual: - Hyphenated references to keys such as CONTROL-V and META-V mean that two keys are to be pressed simultaneously.(This applies to the light beige keys with dark lettering.) For instance, you can generate CONTROL-V by holding down the first key (CONTROL) and pressing the second key (V). Unhyphenated references to keys such as SELECT A mean that keys are to be pressed sequentially.(This applies to the light beige keys with white lettering.) For example, you can generate FUNCTION REFRESH by pressing first the FUNCTION key and then the REFRESH key. - 3This font will be used to display examples of words and prompts that will appear on the Browser screen. 0 - 1This italic font will be used to display "placeholder" words in messages and command descriptions -- these are used to describe the kind of data that should be entered or that will be printed. The surrounding text will describe what you will actually see or what you should actually use in place of these words. 0 - 2This boldface font will be used to display important words and concepts. 0  chapter br-chapter-3 53. Running the Browser 0 It is a simple matter to get to the Browser from any of the other Computer * Thought programs that run on your Lisp Machine. Eventually, the C*T Ada Interpreter and Browser will be tied together directly so that you can access the 1Ada Language Reference Manual0 immediately whenever the interpreter issues an error message citing reference manual sections. Currently, however, you should follow the steps outlined below to enter and exit the Browser.  section br-section3-1 63.1. Entering the Browser 0 To enter the Browser, do the following: 1. Type SELECT B to invoke the Browser process. 2. You will halt the current program and switch to the Browser. The first screen that appears contains four windows, which are discussed in Chapter 4.  section br-section3-2 63.2. Exiting the Browser 0 After you enter the Browser, you remain there until you do one of the following: 1. Press FUNCTION B to "bury" the Browser window and return to where you were before you invoked the Browser. For example, if you were in the Interpreter/Debugger, you would return to the exact portion of the program that was running when you switched to the Browser. 2. Select a different process, such as ZMACS (SELECT E) or a Lisp Listener (SELECT L). If you do this, you will eventually need to press FUNCTION B several times to return to where you were before you entered the Browser. 3. Start up a new Interpreter/Debugger by pressing SELECT A.  section br-section3-3 63.3. Using the REFRESH Key 0 There are two occasions when you may need to press the REFRESH key to restore the screen windows to their previous state. The first case is when you press SUSPEND to enter a Lisp break for some reason (this should seldom if ever occur). After you return to the Browser by pressing the RESUME key, you will need to press the REFRESH key to redraw the Browser's windows. The second case is when you hit the ABORT key to exit Text Viewing mode (see Section 5.2.5). In this instance, you will need to refresh the screen by pressing the REFRESH key the next time you enter Text Viewing mode. Again, this should seldom happen, since there are better ways to exit from Text Viewing mode than by aborting it.  section br-section3-4 63.4. Using the Mouse to Select Menu Items 0 Regardless of which Browser window configuration is currently on the screen, you use the same method to select menu items from windows: you select them with your mouse. You will notice that pointing at a menu item with your mouse encloses it in a box. If you move the mouse pointer away at this stage, the item is not selected and the box disappears. However, if you point at the item and click the left button, this will bring up new screen contents corresponding to the item selected. This method of selection is called 2clicking0 on an item.  chapter br-chapter-4 54. Browsing Through a Document 0 When you invoke the Browser, four windows will appear on the screen as shown in Figure 4-1. When this window configuration is on the screen you are in 2Browsing Mode0. In this mode, you can navigate through the chapters, sections and subsections of a document until you reach a point where you would like to start reading the text. This chapter tells how to find and select the text of the document you want to view. Chapter 5 discusses ways of paging through the actual text once it has been selected for viewing. Figure 4-1: Browser Windows in Browsing Mode  section br-section4-1 64.1. Screen Windows in Browsing Mode 0 The four windows displayed in Browsing mode are: - the Main window (the large, unlabelled window), - the Documents window, - the Previous Positions window, and - the Browser Selection window. Each of these windows is described in the remainder of this section.  subsection br-section4-1-1 74.1.1. Main Window 0 The Main window, the largest interactive window in the four-window configuration, is used to navigate through the structure of available documents. This process is similar to moving through nodes of a 2tree0 structure: you can branch to different parts of the document by taking the appropriate path. The contents of this window always show the options that are currently available to you at any node within the tree. Figure 4-2 shows some paths in a typical tree structure. The example in Figure 4-3 shows the paths you might take to get directly to 3Subsection 2.2.30 in the Browser or, by cross-referencing, to get to 3Section 3.20 in the Interpreter/Debugger. When the Browser is first invoked, the Main window displays the top node in the tree: a menu of the documents currently available through the Browser. These appear in boldface and are longer names for corresponding entries in the Documents window. The standard contents of the first screen to appear in the Main window are shown below and in Figure 4-4: 3 You are currently at "Available Documents" Documents: The Browser User Manual The Interpreter/Debugger User Manual 0 If you select, for example, 3The Interpreter/Debugger User Manual0, a chapter level table of contents for that manual will appear on your screen. This table of contents serves as a menu from which you can select individual chapters. In Figure 4-5, 3Chapter 40 is being selected. When you click on a chapter, a new menu will appear (Figure 4-6), showing all the options that are now open to you at this level in the manual. For example, you can go: - Up to return to the containing document (the Table of Contents), - Down to a particular section within the chapter, Figure 4-2: Sample Node in a Typical Tree Configuration UP 9D 0 | | | ------- | | BACKWARD<------| |------>FORWARD ---| |--- | ------- | | | | ------ CROSS---------| | |---------|READ| REFERENCE | |TEXT| 9C0 |----| DOWN |----| ------ Figure 4-3: Sample Nodes in a Typical Tree Configuration Available Documents | | BROWSER________________INTERP/DEBUG | | | | Table of Contents 1 Table of Contents 2 | | | | | | | | | | | | | | | | | | | | | | | | | | | | Chapter 1 2..............7 Chapter 1 2..............7 | | | | Chapter 2 CR RT Chapter 2 CR RT | | ____________________ ____________________ | | | | | | | | | | | | | | | | | | | | Section 2.1 2.2.....2.4 CR RT Section 2.2 2.3 CR RT | | | | Section 2.2 Section 3 | | _____________________ ________________ | | | | | | | | | | | | | | | | | | Subsection 2.2.1....2.2.3 CR RT Section 3.1 3.2 CR RT | | | | text text - Back to the previous chapter, - Forward to the next chapter, - Directly to the text of the chapter to start reading it from the beginning, or - Over to a cross referenced portion of the document, if any exist.[This menu item is particularly relevant to the Ada Language Reference Manual (LRM), which uses extensive cross referencing in its text.] If you click on the 3read the text0 option, you will go into Text Viewing mode as described in Chapter 5. The rest of the options take you to other menus of currently-available choices, rather than into the document itself. Figure 4-6 shows 3Section 4.20 within 3Chapter 40 being selected. From there you will get a menu of new choices (Figure 4-7), similar to those we have already seen. You can choose to go: - Up (in the menu tree structure) to the containing chapter, - Down to select a subsection, if any exist, - Forward to the next section, - Backward to a previous section, - Directly to view the text of the currently-selected section, or - Over to a cross-referenced location, if there are any. For example, if you click on 3Cross References0, the pop-up menu shown below will appear, listing all the chapter and section references that are related to the current topic. You can either select one of these and go to that location, or stay where you are by moving the mouse pointer away from the pop-up menu. If you select a cross referenced chapter or section, you will get a new set of options available at that level. Within the Main window, you can continue to navigate back and forth throughout the document in this manner until you reach a point where you would like to view the text of the document itself. A record of where you have been in this browsing process is maintained in the Previous Positions window which is discussed in Section 4.1.3.  subsection br-section4-1-2 74.1.2. Documents Window 0 The 2Documents window0 provides a menu from which you can always select one of the Browser's main documents. There are two standard choices available: 1. INTERP/DEBUG (The Computer * Thought Ada Interpreter/Debugger User Manual), and 2. BROWSER (The Computer * Thought Documentation Browser User Manual). If your configuration includes other optional C*T programs, the Documents window may also display one or both of the following: 1. LRM (Ada Language Reference Manual), and/or 2. ADA MODE (The Computer * Thought Ada Mode for ZMACS User Manual) If you click on INTERP/DEBUG, the Browser takes you to the Table of Contents of the Interpreter/Debugger manual. Figure 4-8 shows this manual being selected. Similarly, if you click on BROWSER, the Table of Contents of this Browser manual will appear in the Main window. Notice that the selections shown in Figures 4-4 and 4-8 will produce identical results: either causes another screen to appear showing a chapter-level 2Table of Contents0.  subsection br-section4-1-3 Figure 4-4: Selecting a Manual from the Main Window Figure 4-5: Selecting a Chapter from the Table of Contents Figure 4-6: Selecting a Section Within a Chapter Figure 4-7: Selecting a Subsection Within a Section Figure 4-8: Selecting a Manual from the Documents Window 74.1.3. Previous Positions Window 0 The window at the upper left portion of the screen is called the 2Previous Positions window0. The entries in this window are like bookmarks: they save your place while you switch to another page or even another document. Specifically, this window contains a history of the last seven places you have visited within the Browser. Every time you move from one place to another, the position you're leaving appears at the top of this list. For example, if you just left 3Section 4.20, the Previous Positions window might contain the following entries: 3 Interp/Debug: Section 4.2: Menus Interp/Debug: Chapter 4: The Interpreter/Debugger's Use of Windows Interp/Debug: The Interpreter/Debugger User Manual Available Documents 0 You can return to any of the last seven places you've been by clicking on any of the items in this window with your mouse. Using this built-in feature, you can easily get back to where you were if you go somewhere you didn't intend to, or to a place that doesn't contain the information you thought it would. Figure 4-9 shows the Interpreter/Debugger manual Table of Contents being selected from the Previous Positions Window. This figure, Figure 4-4 and Figure 4-8 all show alternative methods of obtaining the Table of Contents menu (Figure 4-5) in the Main window. Figure 4-9: Selecting a Location from the Previous Positions Window  subsection br-section4-1-4 74.1.4. Browser Selection Window 0 The 2Browser Selection window0 expands your set of bookmarks still further, to use the previous analogy. Now you can have multiple sets of bookmarks, with each set numbered (1, 2, and so forth) to distinguish them. Suppose that you enter the Browser to look up 3Section 4.2.30 of the Interpreter/ Debugger manual. You go through several menus and finally get to the topic you are looking for. As in Figure 4-10, there are five entries in the Previous Positions window and there is only one entry in the Browser Selection window: 3 Create New Browser 0 Figure 4-10: Creating a New Browser When you click on this entry, the Browser creates another document structure called Browser 2. There are no entries yet in the Previous Positions window of this new Browser. Let's say you now search for 3Section 6.1.10 in the on-line version of this Browser manual, going through several menus to find what you need. At this point (Figure 4-11), there are multiple entries in the Previous Positions window and two menu items in the Browser Selection window of Browser 2: 3 Create New Browser Select Old Browser 0 You can quickly get back to your 3Section 4.2.30 topic by clicking on 3Select Old Browser0. A pop-up menu will appear, showing your most recent location in the old Browser: 3 Browser 1: Interp/Debug: Section 4.2.3: Command Menus 0 Figure 4-11: Selecting an Old Browser Figure 4-12: Selecting from among Several Browsers If you click on this menu item, you will return to the same screen you were in before you switched Browsers. You will notice that you can create more than two Browsers at a time. Theoretically, you can select from any number of old Browsers you create: each Browser will be numbered and have its own history recorded in the Previous Positions window. From a practical standpoint, however, using more than three or four Browser document structures at a time is apt to get confusing. Figure 4-12 shows a pop-up menu with several old Browsers to choose from. The most useful reason for creating multiple Browsers is to separate your topic searches or document searches from one another for clarity's sake.  subsection br-section4-1-5 74.1.5. Mouse Documentation Line 0 The reverse video line at the very bottom of the screen is called the 2Mouse Documentation Line0. When the mouse is moved over different item selections on the menu, the Mouse Documentation Line displays a brief description of the function of that command. You do not have to select an item to view this documentation. As you move the mouse from one item to another, the contents of the Mouse Documentation Line will change to describe the item to which the mouse is currently pointing.  chapter br-chapter-5 55. Viewing the Text of a Document 0 This chapter explains how to page through the actual text of a document after you have selected it for viewing. When you select 3Read the Text0, as in Figure 5-1, from one of the menus in the Main window, you will switch from the Browser's 2Browsing mode0 discussed in Chapter 4 to the 2Text Viewing mode0. In this mode you will be viewing the actual text of the document rather than its structural layout. Figure 5-1 shows you selecting a sample section of the Interpreter/Debugger User Manual to read in the Text Viewing mode. Figure 5-1: Selecting a Section From Browser Mode to Read in Text Viewing Mode  section br-section5-1 65.1. Browser Windows in Text Viewing Mode 0 Figure 5-2 shows the text that was selected in Figure 5-1. The text file window configuration contains two windows: one displaying the actual text and another containing a vertical series of commands and arrow symbols. The vertical bar to the right of the text window is also meaningful, as you will see in the following discussions. Figure 5-2: Screen Windows in Text Viewing Mode  subsection br-section5-1-1 75.1.1. Text Window 0 This large window displays the pages of the chapter, section, or subsection you selected for viewing. Starting with the first page, you can move around in the selected document using commands from the Command window.  subsection br-section5-1-2 75.1.2. Vertical Bar 0 The amount of this bar shown in boldface signifies the percentage of the text that fits within the page you are viewing. For example, if the entire bar is boldface (as in Figure 5-2 above), then the entire chapter, section or subsection you selected fits on this single page. Likewise, if midway down the screen a small portion of the bar appears in boldface, you are viewing a page that lies midway between the beginning and end of a large text unit. This is the case in Figure 5-3, which shows a page in the middle of Chapter 3 in the Interpreter/Debugger user manual. Figure 5-3: Viewing Part of a Large Text Unit  subsection br-section5-1-3 75.1.3. Command Window 0 This window contains a vertical series of commands and arrow symbols. While you can use your mouse to click on any of them, the Browser will only allow you to select a command when it appears in boldface. When a command appears non-boldface with a line drawn through it, this "ghost" indicates that the command is not appropriate to the currently-selected text. For example, if you are at the beginning of the text you cannot execute a PREVIOUS PAGE command. Similarly, if there are no cross references in the text you cannot jump to one using the XREF command.  section br-section5-2 65.2. Text Viewing Commands 0 Text viewing commands include paging commands, commands to move between text units, a command to switch to a cross referenced text unit, and a command to exit the current document.  subsection br-section5-2-1 75.2.1. Paging Commands (9A0, 9B0, 9C0, 9D0) Figure 5-4 shows you the command keys to use to move through the text. You can move to the last page of a file by clicking on the LAST PAGE (9A0) symbol, or to the first page by clicking on the FIRST PAGE (9B0) symbol. Similarly, you can move forward in the file by clicking on the NEXT PAGE ([ 9C0]) symbol, and backward by clicking on the PREVIOUS PAGE (9D0) symbol. If you click the 2left0 button of your mouse on the NEXT PAGE or PREVIOUS PAGE arrows, you will move forward or backward through the text by page. Clicking the 2right0 mouse button on these symbols will move you line by line. The Browser will not allow you to choose the FIRST PAGE or PREVIOUS PAGE arrows when you are already at the beginning of the file, or the LAST PAGE or NEXT PAGE arrows when you are already at the end of the file. Figure 5-4: Moving Through the Text Using Paging Commands  subsection br-section5-2-2 75.2.2. ZMACS Paging Commands 0 If you wish, you may use ZMACS keyboard commands rather than your mouse to page through a text file. The keystrokes for NEXT PAGE are CONTROL-V, and for PREVIOUS PAGE are META-V. Similarly, CONTROL-N takes you to the next line; CONTROL-P to the previous line. META-< and META-> also work as they do in ZMACS: they take you to the beginning and end of the buffer, respectively. Refer to the documentation supplied with your Lisp Machine workstation for more information.  subsection br-section5-2-3 75.2.3. Navigating Commands (PREV, NEXT) 0 Using these two commands, you can move forward or backward between any text units that are at the same hierarchical level as the text you are viewing. PREV will take you directly to the text of the previous block, while NEXT will take you directly to the text of the next one. For example, if you are viewing a chapter, you can move to the text of the previous or next chapter using these commands. If you are viewing a subsection, you can move to the text of the previous or next subsection. And so forth. If no previous or next text unit exists at the current level, you won't be able to select the corresponding command. As with NEXT in Figure 5-5, the command will appear non-boldface with a line drawn through it, indicating that you may not select it. Figure 5-5: Moving Through the Text Using Navigating Commands  subsection br-section5-2-4 75.2.4. XREF Command 0 Most documents contain cross references to related portions of the same or different documents. If the text you are reading contains such cross references, you can use the XREF command to move directly to the text of one of these references. A menu, such as the one shown in Figure 5-6, will appear showing all of the choices from which to select. This command is similar to the cross reference capability described in Section 4.1.1, but with one important difference: clicking on XREF will take you directly to the 2text0 you want to read. Clicking on the words 3Cross References0 in Browsing mode will take you to the table of contents level where that cross reference is found. If the XREF command does not appear in boldface, there are no cross references in the text you are viewing, and you cannot select this command. Figure 5-6: Using the Cross Reference Command  subsection br-section5-2-5 75.2.5. EXIT Command 0 When you have finished reading the text, click on the EXIT command to return to Browsing mode -- you'll be at the same place you were before you started viewing the text. There is another way to exit quickly from the Text Viewing mode: you can press the CONTROL and ABORT keys simultaneously. If, for example, you elected to view the text of an entire chapter, then realized you only wanted a particular section within it, you could press CONTROL-ABORT to get back to the menu immediately and make another selection. Using the ABORT key alone is equivalent to clicking on the EXIT command: you have to wait for the file to finish reading into the text window before you can exit Text Viewing mode. If you use the ABORT key, you will need to press REFRESH to restore the screen the next time you read text.  chapter br-chapter-6 56. Sample Browsing Session 0 Two examples have been provided below to give you a step-by-step guide for moving through the Browser. In the following examples, the Browser will be used to demonstrate how you can quickly locate information in the Interpreter/Debugger by using the on-line documentation system.  section br-section6-1 66.1. Reading the Text in the Interpreter/Debugger 0 Let's suppose that you wish to read the text explanation of the Command Menus while operating the C*T Ada Interpreter. To look up that information in the user manual, you would go through the following steps: 1. Type 3SELECT B0 to enter the Browser. 2. Click on the 3Interpreter/Debugger User Manual0 menu entry in the Main window, or 3INTERP/DEBUG0 in the Documents window. 3. When the Table of Contents appears in the Main window (Figure 6-1), click on 3Chapter 4: The Interpreter/Debugger's Use of Windows0. 4. When the next screen appears (Figure 6-2), click on: 3 Down to Sections: Section 4.2: Menus 0 5. When the last menu screen appears (Figure 6-3), click on: 3 Down to Subsections: Section 4.2.3: Command Menus 0 6. To read the current text (Figure 6-4), click on: 3 Read the text: Section 4.2.3: Command Menus 0 7. The next screen (Figure 6-5) will display the beginning of the text of Section 4.2.3. Notice that the solid bold column on the right side of the screen (the Vertical Bar) indicates that you are in a document with only one page. If the document were longer, you would need to page forward by using the Paging Command arrows in the Command window or by using CONTROL-V, until you located the desired text. 8. If you wish to refer to other areas in the manual for additional information, click the mouse on the cross reference symbol in the Command window. A pop-up menu, such as the one in Figure 6-6, will appear on the left side of the screen. Click on Section 4.3 in the cross reference menu to go directly to the text of that section. To return to the text of Section 4.2.3, click on EXIT in the Command window. This will send you back to the Table of Contents where you can re-select Section 4.2.3 from the Previous Positions window. 9. If you wish to view the text of any other sections in this same hierarchy, that is Section 4.2.1 or Section 4.2.2, click on the PREV symbol in the Command window. 10. When you have finished looking at the relevant text, click on EXIT in the Command window. You will return to the immediately preceding multi-choice screen, the one corresponding to Section 4.2.3. Figure 6-1: Selecting Chapter 4: The Interpreter/Debugger's Use of Windows Figure 6-2: Selecting Section 4.2: Menus Figure 6-3: Selecting Section 4.2.3: Command Menus Figure 6-4: Read the Text of Section 4.2.3 Figure 6-5: Viewing the Text of Section 4.2.3 Figure 6-6: Cross References for Section 4.2.3  section br-section6-2 66.2. Getting Help With An Error Message 0 Let's suppose that while you are running the C*T Ada Interpreter you encounter the following semantic error message: 3 The label 1label3 referenced by the 'goto' statement in line 1number 3 is not directly in an enclosing construct for the goto. Description: LRM Section 5.9, Paragraph 1 Example: LRM Section 5.9, Paragraph 6 0 To locate the meaning of the error message you must go through the following steps: 1. Type 3SELECT B0 to enter the Browser 2. Click on the 3Interpreter/Debugger User Manual0 menu entry in the Main window, or 3INTERP/DEBUG0 in the Documents window. 3. When the Table of Contents appears in the Main window, click on 3Chapter 3: The Computer * Thought Ada Interpreter0 as shown below in Figure 6-7. 4. When the next screen appears (Figure 6-8), click on: 3 Down to Sections: Section 3.2: Interpreter Error Messages 0 5. To read the text of Section 3.2 (Figure 6-9), click on: 3 Read the Text: Section 3.2: Interpreter Error Messages 0 Beginning with page 1, the text of Section 3.2 should be displayed on your screen as shown in Figure 6-10. 6. The Vertical Bar to the right of the screen indicates that you are at the beginning of a long document. Since the error messages are arranged in alphabetical order, you will need to page to the middle of the document. Use the Paging Command arrows in the Command window or type a series of 3CONTROL-V0s to reach the error messages beginning with the letter 3L0. 7. Once you have reached the reference to your error message and read the text, as shown in Figure 6-11, you may wish to switch from the Browser to the ZMACS editor so that you can correct your Ada source file. If so, type 3SELECT E0. If your site has the Ada Mode for ZMACS program installed, you can enter Ada mode to correct your Ada source file. 8. When you have corrected your file, you can reenter the Interpreter/Debugger by typing 3FUNCTION B0 twice to "bury" the previous two processes (the Browser and the Editor). You will reenter the Interpreter/Debugger exactly where you left it. 9. To exit from the current text and return to the Table of Contents, click on the EXIT symbol in the Command window. You will be returned to the screen displaying Section 3.2 in the Main window. Figure 6-7: Selecting Chapter 3 from the Interpreter/Debugger Manual Figure 6-8: Selecting Section 3.2: Interpreter Error Messages Figure 6-9: Read the Text of Section 3.2 Figure 6-10: Viewing Page 1 of the Text of Section 3.2 Figure 6-11: Reading the Error Message in Section 3.2