\FONT=ELITE \HCI=12 \H1=TEXT:"SYSTEM MANAGER INFORMATION" \H2=TEXT:"The EDX dictionary" \FONT=COURIER \HCI=10 \CONTENTS=1 APPENDIX D: SYSTEM MANAGER INFORMATION \FONT=COURIER \HCI=10 THE EDX DICTIONARY \FONT=ELITE \HCI=12 Source In the course of putting together the lexical database for the EDX spelling checker it was discovered that the 90,000 word lexical database supplied with the popular Vassar spelling checker contains about 20,000 words which are definitely misspelled. This is basically how we arrived at our current list of 70,000 words. Thus, although the EDX spelling checker dictionary is slightly smaller, at least all of the words are correctly spelled. All of the words in the lexical database file DICTIONARY.LEX have been cross checked against two separate spelling checkers commercially available for home personal computers. These are: The Random House Proofreader program version 2.00, and the WordPerfect Speller from WordPerfect version 5.1. Words not recognized by either of the above two spelling checkers were carefully researched and reviewed by two highly experienced editing consultants and myself to determine if the word should be included in the lexical database. The words in the common word list file COMMONWORDS.LEX came from "The American Heritage Word Frequency Book, copyright 1971 by American Heritage Publishing Co, Inc.". Adding words to the EDX dictionary The system manager may occasionally wish to add some new words to the EDX dictionary database file EDX_DICTIONARY.DAT. In order to add new words, remove words, edit words, or in any way change the EDX dictionary database file, it is necessary to create a new database file. This is a fairly easy procedure. It is not as difficult as it may first sound. 1. Locate the files EDX_BLDDIC.MAR and EDX_BLDDIC.COM. They should be in SYS$LIBRARY. These files were supplied along with the EDX editor. Copy these files to your own scratch directory. 2. Invoke the EDX editor and enter the following line mode command: * TPU DUMP_DICTIONARY This will dump all of the words in the EDX lexical database into a buffer. You may then edit the list of words as you wish, adding whatever new words you like. When finished write this buffer to disk calling it DICTIONARY.NEW  3. While still in the EDX editor, enter the following line mode command: * TPU DUMP_COMMONWORDS  This will dump all of the words in the EDX common word database into a buffer. You need not make any modifications to this list. Keep in mind if you do modify this list that the list should be short, approximately 100 words or less, and ordered by frequency of use, with the most frequently used word first. When finished write this buffer to disk calling it COMMONWORDS.LEX 4. Exit the EDX editor, returning to DCL. 5. Sort the file DICTIONARY.NEW creating DICTIONARY.LEX. It is very important this file be correctly sorted with no duplicate entries: $ SORT/NODUPLICATES DICTIONARY.NEW DICTIONARY.LEX 6. Run EDX_BLDDIC.COM. This comfile will compile, link, and run EDX_BLDDIC.MAR, creating a new EDX dictionary database file EDX_DICTIONARY.DAT $ @EDX_BLDDIC.COM 7. Replace the old SYS$LIBRARY:EDX_DICTIONARY.DAT file with your newly created EDX_DICTIONARY.DAT \FONT=ELITE \HCI=12 \H1=TEXT:"SYSTEM MANAGER INFORMATION" \H2=TEXT:"Limitations of VAXTPU" \FONT=COURIER \HCI=10 LIMITATIONS OF VAXTPU \FONT=ELITE \HCI=12 File Size Limitations Currently a typical user process with an authorized page file quota of 10,240 is limited to a maximum file size of approximately 40,000 lines or 6000 blocks. This is due to the memory allocation limitations of a user's process. Since VAXTPU reads the entire file into virtual memory when it starts up, if the file is too big, it results in the error TPU-E-NOCACHE or TPU-E-GETMEM. (As of VMS 4.4 these errors lead directly to Fatal Internal VAXTPU Errors. EDX attempts to detect these errors and will advise the user to save everything and exit immediately if such an error should occur.) Increase your page file quota (pgflquo in authorize database) if you need to edit a larger file. \FONT=COURIER \HCI=10 INTERNAL VAXTPU ERRORS \FONT=ELITE \HCI=12 Internal VAXTPU bug on VMS 5.3 VMS 5.3 introduced a new bug to VAXTPU causing messages at the bottom of the screen not to appear properly for earlier versions of EDX. EDX version 7.4 works around the bug so it will work properly on VMS 5.3. (EDX version 6.2 also attempted to work around the problem but was not as successful.) Fatal Internal VAXTPU errors on VMS 5 Most of the fatal VAXTPU bugs on VMS 4 were fixed by VMS 5, however there was at least one new bug introduced on VMS 5. The EDX editor attempts to avoid conditions that can lead to a fatal error as much as possible. Known sources of fatal internal TPU errors on VMS 5 are: 1. Windows. New as of VMS 5.0, VAXTPU will bugcheck if the visible_length of a window is less than the scroll_top + scroll_bottom + scroll_amount. Versions of EDX prior to EDX version 5.0 encountered this fatal internal VAXTPU error when the line mode command ADJUST WINDOWS was executed. The ADJUST WINDOWS routine has been modified on EDX version 5.0 to avoid this possibility. 2. New as of VMS 5.3, if the user mapped the bottom window for the first time to an existing buffer with the cursor position somewhere in the middle of the buffer, and immediately attempted to enter text, a fatal internal error would result. EDX version 7.4 fixes this problem by temporarily silently mapping the bottom window during initialization. Thus when the user first goes to the bottom window, it is not the first time the window has been mapped. Fatal Internal VAXTPU errors on VMS 4 As of VMS 4.4 there are numerous known conditions which can lead to fatal internal VAXTPU errors. The EDX editor attempts to avoid these conditions as much as possible. Known sources of fatal internal VAXTPU errors are: 1. Creating a buffer without sufficient memory to allocate for the new buffer. The EDX editor attempts to detect this condition and will advise the user to save his work and exit immediately if the condition is detected. (See the explanation in procedure EDTN$CREATE_BUFFER in file EDTSCNSEC.TPU.) Fixed in VMS 5.0. 2. Deleting buffers can lead to fatal internal VAXTPU errors or to an infinite loop depending upon the circumstances. Deleting buffers works OK if the procedure which deletes a buffer exits back to the user without doing anything else. However, if a procedure deletes a buffer and then returns to some other procedure which called it, then, when the calling procedure exits, VAXTPU may, depending upon the circumstances, encounter a fatal internal error. An obscure example of this is the EDT mode key sequence GOLD CTRL-L (find line number) followed immediately by the line mode command FIX CRLFS. This will cause a fatal internal VAXTPU error if the current buffer was created with a specified file read into the buffer at the time of creation. This problem has reportedly been fixed as of VMS 4.6. 3. The continuous scroll command (GOLD up arrow and GOLD down arrow) only works if the screen is not being updated when key command sequence is entered. Otherwise the message 'Press any key to stop scrolling' is displayed but the screen does not scroll. This is due to the internal structure of VAXTPU and how it buffers and executes key strokes. 4. The built-in GET_INFO(DEBUG,...) is known to be broken. It is used in the TPU debugger SYS$LIBRARY:DEBUG.TPU to examine local variables and parameters. When using the debugger to debug a procedure you could avoid declaring local variables in your procedure and only examine global variables. Examining global variables does not use the above built-in. Fixed in VMS 5.0. 5. The pattern matching built-in SPANL is known to be broken. This built-in is not used in this section file. Fixed in VMS 5.0.