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4<TITLE>GNU ISPELL V4.0 - GNU ISPELL</TITLE> 
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6<H1><A NAME="SEC2" HREF="ispell_toc.html#SEC2">GNU ISPELL</A></H1> 
7<CODE>Ispell</CODE> is a program that helps you to correct typos in a file, 
8and to find the correct spelling of words.  When presented with a 
9word that is not in the dictionary, <CODE>ispell</CODE> attempts to find 
10<DFN>near misses</DFN> that might include the word you meant. 
11<P> 
12This manual describes how to use ispell, as well as a little about 
13its implementation. 
14<P> 
15<H2><A NAME="SEC3" HREF="ispell_toc.html#SEC3">Using ispell from emacs</A></H2> 
16<P> 
17<H3><A NAME="SEC4" HREF="ispell_toc.html#SEC4">Checking a single word</A></H3> 
18<P> 
19The simplest emacs command for calling ispell is 'M-$' (meta-dollar. 
20On some terminals, you must type ESC-$.) This checks the spelling of 
21the word under the cursor.  If the word is found in the dictionary, 
22then a message is printed in the echo area.  Otherwise, ISPELL 
23attempts to generate near misses.  
24<P> 
25If any near misses are found, they are displayed in a separate window, 
26each preceded by a digit.  If one of these is the word you wanted, 
27just type its digit, and it will replace the original word in your 
28buffer. 
29<P> 
30If no near miss is right, or if none are displayed, you 
31have four choices: 
32<P> 
33<DL COMPACT> 
34<DT><KBD>I</KBD> 
35<DD><P> 
36Insert the word in your private dictionary.  Use this if you 
37know that the word is spelled correctly. 
38<P> 
39<DT><KBD>A</KBD> 
40<DD><P> 
41Accept the word for the duration of this editing session, but do not 
42put it in your private dictionary.  Use this if you are not sure about 
43the spelling of the word, but you do not want to look it up 
44immediately.  The next time you start ispell, it will have forgotten 
45any accepted words.  You can make it forget accepted words at any time 
46by typing <KBD>M-x reload-ispell</KBD>. 
47<P> 
48<DT><KBD>SPC</KBD> 
49<DD><P> 
50Leave the word alone, and consider it misspelled if it is checked again. 
51<P> 
52<DT><KBD>R</KBD> 
53<DD><P> 
54Replace the word.  This command prompts you for a string in the 
55minibuffer.  You may type more than one word, and each word you type 
56is checked again, possibly finding other near misses.  This command 
57provides a handy way to close in on a word that you have no idea how 
58to spell.  You can keep trying different spellings until you find one 
59that is close enough to get a near miss. 
60<P> 
61<DT><KBD>L</KBD> 
62<DD><P> 
63Lookup.  Display words from the dictionary that contain a 
64specified substring.  The substring is a regular expression, 
65which means it can contain special characters to be more 
66selective about which words get displayed. 
67See section `Regexps' in <CITE>emacs</CITE>. <P> 
68If the only special character in the regular express is a leading 
69<CODE>^</CODE>, then a very fast binary search will be used, instead of 
70scanning the whole file. 
71<P> 
72Only a few matching words can be displayed in the ISPELL window. 
73If you want to see more, use the <CODE>look</CODE> program directly from 
74the shell. 
75</DL> 
76<P> 
77Of course, you can also type ^G to stop the command without 
78changing anything. 
79<P> 
80If you make a change that you don't like, just use emacs' normal undo 
81feature See section `undo' in <CITE>emacs</CITE>. 
82<P> 
83<H3><A NAME="SEC5" HREF="ispell_toc.html#SEC5">Checking a whole buffer</A></H3> 
84<P> 
85If you want to check the spelling of all the words in a buffer, type 
86the command <KBD>M-x ispell</KBD>.  This command scans the file, and makes 
87a list of all the misspelled words.  When it is done, it moves the 
88cursor to the first word on the list, and acts like you just typed M-$ 
89See section <A HREF="ispell_2.html#SEC4">Checking a single word</A>. 
90<P> 
91When you finish with one word, the cursor is automatically moved to the 
92next.  If you want to stop in the middle of the list type <KBD>Q</KBD> or 
93<KBD>^G</KBD>.  Later, you can pick up where you left off by typing 
94<KBD>C-X $</KBD>. 
95<P> 
96<H3><A NAME="SEC6" HREF="ispell_toc.html#SEC6">Checking a region</A></H3> 
97<P> 
98You may check the words in the region with the command M-x ispell-region. 
99See See section `mark' in <CITE>emacs</CITE>. 
100<P> 
101The commands available are the same as for checking a whole buffer. 
102<P> 
103<H2><A NAME="SEC7" HREF="ispell_toc.html#SEC7">Old Emacs</A></H2> 
104<P> 
105Until ispell becomes part of the standard emacs distribution, you will 
106have to explicitly request that it be loaded.  Put the following lines 
107in your emacs init file See section `init file' in <CITE>emacs</CITE>. 
108<P> 
109<PRE> 
110(autoload 'ispell "ispell" "Run ispell over buffer" t) 
111(autoload 'ispell-region "ispell" "Run ispell over region" t) 
112(autoload 'ispell-word "ispell" "Check word under cursor" t) 
113(define-key esc-map "$" 'ispell-word) 
114</PRE> 
115<P> 
116(It will do no harm to have these lines in your init file even after 
117ispell is installed by default.) 
118<P> 
119<H2><A NAME="SEC8" HREF="ispell_toc.html#SEC8">Using ispell by itself</A></H2> 
120<P> 
121To check the words in a file, give the command <CODE>ispell FILE</CODE>.  This 
122will present a screen of information, and accept commands for every word 
123that is not found in the dictionary. 
124<P> 
125The screen shows the offending word at the top, as well as two lines of 
126context at the bottom.  If any near misses are found, they are shown in the 
127middle of the screen, each preceded by a digit. 
128<P> 
129You may use the same commands as inside of emacs to accept the word, 
130place it in your private dictionary, select a near miss, or type a 
131replacement See section <A HREF="ispell_2.html#SEC4">Checking a single word</A>.  You may also choose from the following 
132commands: 
133<P> 
134<DL COMPACT> 
135<DT><KBD>?</KBD> 
136<DD><P> 
137Print a help message. 
138<P> 
139<DT><KBD>Q</KBD> 
140<DD>Quit.  Accept the rest of the words in the file and exit. 
141<P> 
142<DT><KBD>X</KBD> 
143<DD>Exit.  Abandon any changes made to this file and exit immediately.  You 
144are asked if you are sure you want to do this. 
145<P> 
146<DT><KBD>!</KBD> 
147<DD>Shell escape.  The shell command that you type is executed as 
148a subprocess. 
149<P> 
150<DT><KBD>^Z</KBD> 
151<DD>Suspend.  On systems that support job control, this suspends ISPELL. 
152On other systems it executes a subshell. 
153<P> 
154<DT><KBD>^L</KBD> 
155<DD>Redraw the screen. 
156</DL> 
157<P> 
158If you type your interrupt character (usually ^C or <KBD>DEL</KBD>), then 
159ispell will immediately enter its command loop.  If ispell was generating 
160near misses at the time, then all that it had found so far will be 
161displayed, along with a message stating that there might be more, and that 
162you can type <KBD>RET</KBD> to generate them.  If it was scanning the file, it 
163will display <SAMP>`(INTERRUPT)'</SAMP> where it would normally display a bad word, 
164and the commands that change the file will be disabled. 
165<P> 
166The feature is handy if you have left out a space between words, and 
167ispell is futilely looking up the 1000 potential near misses for a 
168string that has twenty letters. 
169<P> 
170<H2><A NAME="SEC9" HREF="ispell_toc.html#SEC9">Using ispell to look up individual words
171</A></H2> 
172<P> 
173When ispell is run with no arguments, it reads words from the standard 
174input.  For each one, it prints a message telling whether it is in the 
175dictionary.  For any words not in the dictionary, near misses are 
176computed, and any that are found are printed. 
177<P> 
178<PRE> 
179% ispell 
180word: independant 
181how about: independent 
182word: xyzzy 
183not found 
184word: ^D 
185</PRE> 
186<P> 
187<H2><A NAME="SEC10" HREF="ispell_toc.html#SEC10">Your private dictionary</A></H2> 
188<P> 
189Whenever ispell is started the file <TT>`ispell.words'</TT> is read from your 
190home directory (if it exists).  This file contains a list of words, one per 
191line, and neither the order nor the case of the words is important.  Ispell 
192will consider all of the words good, and will use them as possible near 
193misses. 
194<P> 
195The <KBD>I</KBD> command adds words to <TT>`ispell.words'</TT>, so normally you 
196don't have to worry about the file.  You may want to check it from 
197time to time to make sure you have not accidentally inserted a 
198misspelled word. 
199<P> 
200<H2><A NAME="SEC11" HREF="ispell_toc.html#SEC11">Compatibility with the traditional spell program
201</A></H2> 
202<P> 
203The <SAMP>`-u'</SAMP> flag tells ispell to be compatible with the traditional 
204<SAMP>`spell'</SAMP> program.  This flag is automatically turned on if the 
205program is invoked by the name <SAMP>`spell'</SAMP>. 
206<P> 
207This flag causes the following behavior: 
208<P> 
209All of the files listed as arguments (or the standard input if none) 
210are checked, and misspellings are printed on the standard output.  The 
211output is sorted, only one instance of each word appears (however, 
212a word may appear more than once with different capitalizations.) 
213<P> 
214You may specify a file containing good words with <SAMP>`+filename'</SAMP>. 
215<P> 
216The troff commands <SAMP>`.so'</SAMP> and <SAMP>`.nx'</SAMP> (to include a file, or 
217switch to a file, respectively) are obeyed, unless you give the flag 
218<SAMP>`-i'</SAMP>. 
219<P> 
220The other <SAMP>`spell'</SAMP> flags <SAMP>`-v'</SAMP>, <SAMP>`-b'</SAMP>, <SAMP>`-x'</SAMP> and 
221<SAMP>`-l'</SAMP> are ignored. 
222<P> 
223By the way, ispell seems to be about three times faster 
224than traditional spell. 
225<P> 
226<H2><A NAME="SEC12" HREF="ispell_toc.html#SEC12">All commands in emacs and standalone modes
227</A></H2> 
228<P> 
229Commands valid in both modes: 
230<P> 
231DIGIT   Select a near miss 
232I       Insert into private dictionary 
233A       Accept for this session 
234SPACE   Skip this time 
235R       Replace with one or more words 
236L       Lookup: search the dictionary using a regular expression 
237<P> 
238Standalone only: 
239<P> 
240Q       Accept rest of file 
241X       Abandon changes 
242!       Shell escape 
243?       Help 
244^Z      Suspend 
245^L      Redraw screen 
246^C      Give up generating near misses, or show position in file 
247<P> 
248Emacs only: 
249<P> 
250M-$                     Check word 
251M-x ispell              Check buffer 
252M-x ispell-region       Check region 
253M-x reload-ispell       Reread private dictionary 
254M-x kill-ispell         Kill current subprocess, and start a new one 
255                        next time 
256^G                      When in M-x ispell, stop working on current 
257                        bad word list 
258^X $                    Resume working on bad word list. 
259<P> 
260<H2><A NAME="SEC13" HREF="ispell_toc.html#SEC13">Definition of a near miss</A></H2> 
261<P> 
262Two words are near each other if they can be made identical with one 
263of the following changes to one of the words: 
264<P> 
265<PRE> 
266Interchange two adjacent letters. 
267Change one letter. 
268Delete one letter. 
269Add one letter. 
270</PRE> 
271<P> 
272Someday, perhaps ispell will be extended so that words that sound 
273alike would also be considered near misses.  If you would like to 
274implement this, see Knuth, Volume 3, page 392 for a description of the 
275Soundex algorithm which might apply. 
276<P> 
277<H2><A NAME="SEC14" HREF="ispell_toc.html#SEC14">Flags to the ispell command</A></H2> 
278<P> 
279Ispell's arguments are parsed by getopt(3).  Therefore, there is 
280considerable flexibility about where to put spaces between arguments. 
281The way to be safe is to give only one flag per dash, and put a space 
282between a flag and its argument. 
283<P> 
284If ispell is run with no arguments, it enters <SAMP>`ask'</SAMP> mode See section <A HREF="ispell_2.html#SEC9">Using ispell to look up individual words
285</A>. 
286With one or more file name arguments, it interactively checks each one. 
287<P> 
288<DL COMPACT> 
289<DT><CODE>-p privname</CODE> 
290<DD>Use privname as the private dictionary. 
291<P> 
292<DT><CODE>-d dictname</CODE> 
293<DD>Use dictname as the system dictionary.  You may also specify a system 
294dictionary with the environment variable ISPELL_DICTIONARY. 
295<P> 
296<DT><CODE>-l</CODE> 
297<DD>List mode.  Scan the file, and print any misspellings on the standard 
298output.  This mode is compatible with the traditional spell program, 
299except that the output is not sorted.  See section <A HREF="ispell_2.html#SEC11">Compatibility with the traditional spell program
300</A>. 
301<P> 
302<DT><CODE>-u</CODE> 
303<DD>Compatibility mode. See section <A HREF="ispell_2.html#SEC11">Compatibility with the traditional spell program
304</A>. 
305<P> 
306<DT><CODE>-a</CODE> 
307<DD>Old style program interface, See section <A HREF="ispell_2.html#SEC15">How other programs can use ispell
308</A>. 
309<P> 
310<DT><CODE>-S</CODE> 
311<DD>New program interface, See section <A HREF="ispell_2.html#SEC15">How other programs can use ispell
312</A>. 
313<P> 
314<DT><CODE>-D</CODE> 
315<DD>Print the dictionary on the standard output with flags. 
316<P> 
317<DT><CODE>-E</CODE> 
318<DD>Print the dictionary on the standard output with all flags expanded. 
319<P> 
320</DL> 
321<P> 
322<H2><A NAME="SEC15" HREF="ispell_toc.html#SEC15">How other programs can use ispell</A></H2> 
323<P> 
324Ispell can be used as a subprocess communicating through a pipe.  Two 
325interfaces are available: 
326<P> 
327<H2><A NAME="SEC16" HREF="ispell_toc.html#SEC16">New style, for EMACS</A></H2> 
328<P> 
329To use this interface, start ispell with the '-S' flag.  Ispell will 
330print a version number and greeting message that looks like: 
331<P> 
332<PRE> 
333(1 "ISPELL V4.0")= 
334</PRE> 
335<P> 
336The number is the version number of the protocol to be spoken over 
337the pipe.  The string is a message possibly of interest to the user. 
338<P> 
339All messages from ispell end in an equal sign, and ispell guarantees not to 
340print an equal sign except to end a message.  Therefore, if you do not want 
341to deal with the greeting, just throw away characters until you get to an 
342equals. 
343<P> 
344Ispell then reads one line commands from the standard input, and 
345writes responses on the standard output. 
346<P> 
347If a command does not start with a colon, then it is considered a 
348single word.  The word is looked up in the dictionary, and if it is 
349found, the response is <CODE>t</CODE>.  If the word is not in the 
350dictionary, and no near misses can be found, then the response is 
351<CODE>nil</CODE>.  If there are near misses, the response is a line containing 
352a list of strings in lisp form.  For example: 
353<P> 
354        INPUT           OUTPUT 
355        the             t 
356        xxx             nil 
357        teh             ("tea" "ten" "the") 
358<P> 
359The near miss response is suitable for passing directly to the lisp 
360<CODE>read</CODE> function, but it can also be parsed simply in C.  In 
361particular, ispell promises that the list will appear all on one line, 
362and that the structure will not change.  A parser that reads the whole 
363line, then treats the parentheses and quotes as whitespace will work fine. 
364<P> 
365The list will contain a maximum of ten strings, and each string will be 
366no longer than 40 characters.  Also, the capitalization of the near 
367misses is the same as the input word. 
368<P> 
369<H3><A NAME="SEC17" HREF="ispell_toc.html#SEC17">Colon commands</A></H3> 
370<P> 
371If the input line starts with a colon, then it is one of the following 
372commands: 
373<P> 
374<CODE>:file <VAR>filename</VAR></CODE> 
375Run the word checker over the named <VAR>filename</VAR>.  The response is zero or 
376more lines each containing a number.  The numbers are file offsets of 
377words that do not appear in the dictionary.  Since the near miss 
378checker is not run, this is fairly fast.  
379<P> 
380After the last number, there will be a line containing either <CODE>t</CODE> if 
381the checker got to the end of the file, or <CODE>nil</CODE> if it received an 
382interrupt.  If ispell ignores any interrupts received except while 
383scanning a file. 
384<P> 
385<CODE>:insert <VAR>word</VAR></CODE> 
386Place <VAR>word</VAR> in the private dictionary. 
387<P> 
388<CODE>:accept <VAR>word</VAR></CODE> 
389Do not complain about <VAR>word</VAR> for the rest of the session. 
390<P> 
391<CODE>:dump</CODE> 
392Write the private dictionary. 
393<P> 
394<CODE>:reload</CODE> 
395Reread the private dictionary. 
396<P> 
397<CODE>:tex</CODE> 
398Enable the tex parser for future <CODE>:file</CODE> commands. 
399<P> 
400<CODE>:troff</CODE> 
401Enable the tex parser for future <CODE>:file</CODE> commands. 
402<P> 
403<CODE>:generic</CODE> 
404Disable any text formatter parsers for future <CODE>:file</CODE> commands. 
405<P> 
406<H2><A NAME="SEC18" HREF="ispell_toc.html#SEC18">Old style, like ITS</A></H2> 
407<P> 
408To use this interface, start ispell with the '-a' flag.  Ispell 
409will read words from its standard input (one per line), and write 
410a one line of output for each one. 
411<P> 
412If the first character of the line is <CODE>*</CODE>, then word was found in the 
413dictionary.  (Other versions of ispell made a distinction between words 
414that were found directly, and words that were found after suffix 
415removal.  These lines began with <CODE>+</CODE>, followed by a space, then 
416followed by the root word.  To remain compatible with these version, 
417treat <CODE>+</CODE> and <CODE>*</CODE> the same.) 
418<P> 
419If the line starts with <CODE>&#38;</CODE>, then the input word was not found, but 
420some near misses were found.  They are listed on the output line 
421separated by spaces.  Also, the output words will have the same 
422capitalization as the input. 
423<P> 
424Finally, if the line starts with <CODE>#</CODE>, then the word was not in the 
425dictionaries, and no near misses were found. 
426<P> 
427        INPUT           OUTPUT 
428        the             * 
429        xxx             # 
430        teh             &#38; tea ten the 
431<P> 
432<H2><A NAME="SEC19" HREF="ispell_toc.html#SEC19">How the suffix stripper works</A></H2> 
433<P> 
434This section is excerpted from the ITS spell.info file. 
435<P> 
436     Words  in SPELL's main dictionary (but not the private dictionary) may 
437have flags associated with  them  to  indicate  the  legality  of  suffixes 
438without  the  need  to keep the full suffixed words in the dictionary.  The 
439flags have "names" consisting of single  letters.    Their  meaning  is  as 
440follows: 
441<P> 
442Let  #  and  @  be  "variables"  that can stand for any letter.  Upper case 
443letters are constants.  "..."  stands  for  any  string  of  zero  or  more 
444letters,  but note that no word may exist in the dictionary which is not at 
445least 2 letters long, so, for example, FLY may not be produced  by  placing 
446the  "Y"  flag  on "F".  Also, no flag is effective unless the word that it 
447creates is at least 4 letters  long,  so,  for  example,  WED  may  not  be 
448produced by placing the "D" flag on "WE". 
449<P> 
450"V" flag: 
451        ...E --&#62; ...IVE  as in CREATE --&#62; CREATIVE 
452        if # .ne. E, ...# --&#62; ...#IVE  as in PREVENT --&#62; PREVENTIVE 
453<P> 
454"N" flag: 
455        ...E --&#62; ...ION  as in CREATE --&#62; CREATION 
456        ...Y --&#62; ...ICATION  as in MULTIPLY --&#62; MULTIPLICATION 
457        if # .ne. E or Y, ...# --&#62; ...#EN  as in FALL --&#62; FALLEN 
458<P> 
459"X" flag: 
460        ...E --&#62; ...IONS  as in CREATE --&#62; CREATIONS 
461        ...Y --&#62; ...ICATIONS  as in MULTIPLY --&#62; MULTIPLICATIONS 
462        if # .ne. E or Y, ...# --&#62; ...#ENS  as in WEAK --&#62; WEAKENS 
463<P> 
464"H" flag: 
465        ...Y --&#62; ...IETH  as in TWENTY --&#62; TWENTIETH 
466        if # .ne. Y, ...# --&#62; ...#TH  as in HUNDRED --&#62; HUNDREDTH 
467<P> 
468"Y" FLAG: 
469        ... --&#62; ...LY  as in QUICK --&#62; QUICKLY 
470<P> 
471"G" FLAG: 
472        ...E --&#62; ...ING  as in FILE --&#62; FILING 
473        if # .ne. E, ...# --&#62; ...#ING  as in CROSS --&#62; CROSSING 
474<P> 
475"J" FLAG" 
476        ...E --&#62; ...INGS  as in FILE --&#62; FILINGS 
477        if # .ne. E, ...# --&#62; ...#INGS  as in CROSS --&#62; CROSSINGS 
478<P> 
479"D" FLAG: 
480        ...E --&#62; ...ED  as in CREATE --&#62; CREATED 
481        if @ .ne. A, E, I, O, or U, 
482                ...@Y --&#62; ...@IED  as in IMPLY --&#62; IMPLIED 
483        if # .ne. E or Y, or (# = Y and @ = A, E, I, O, or U) 
484                ...@# --&#62; ...@#ED  as in CROSS --&#62; CROSSED 
485                                or CONVEY --&#62; CONVEYED 
486<P> 
487"T" FLAG: 
488        ...E --&#62; ...EST  as in LATE --&#62; LATEST 
489        if @ .ne. A, E, I, O, or U, 
490                ...@Y --&#62; ...@IEST  as in DIRTY --&#62; DIRTIEST 
491        if # .ne. E or Y, or (# = Y and @ = A, E, I, O, or U) 
492                ...@# --&#62; ...@#EST  as in SMALL --&#62; SMALLEST 
493                                or GRAY --&#62; GRAYEST 
494<P> 
495"R" FLAG: 
496        ...E --&#62; ...ER  as in SKATE --&#62; SKATER 
497        if @ .ne. A, E, I, O, or U, 
498                ...@Y --&#62; ...@IER  as in MULTIPLY --&#62; MULTIPLIER 
499        if # .ne. E or Y, or (# = Y and @ = A, E, I, O, or U) 
500                ...@# --&#62; ...@#ER  as in BUILD --&#62; BUILDER 
501                                or CONVEY --&#62; CONVEYER 
502<P> 
503"Z FLAG: 
504        ...E --&#62; ...ERS  as in SKATE --&#62; SKATERS 
505        if @ .ne. A, E, I, O, or U, 
506                ...@Y --&#62; ...@IERS  as in MULTIPLY --&#62; MULTIPLIERS 
507        if # .ne. E or Y, or (# = Y and @ = A, E, I, O, or U) 
508                ...@# --&#62; ...@#ERS  as in BUILD --&#62; BUILDERS 
509                                or SLAY --&#62; SLAYERS 
510<P> 
511"S" FLAG: 
512        if @ .ne. A, E, I, O, or U, 
513                ...@Y --&#62; ...@IES  as in IMPLY --&#62; IMPLIES 
514        if # .eq. S, X, Z, or H, 
515                ...# --&#62; ...#ES  as in FIX --&#62; FIXES 
516        if # .ne. S, X, Z, H, or Y, or (# = Y and @ = A, E, I, O, or U) 
517                ...# --&#62; ...#S  as in BAT --&#62; BATS 
518                                or CONVEY --&#62; CONVEYS 
519<P> 
520"P" FLAG: 
521        if @ .ne. A, E, I, O, or U, 
522                ...@Y --&#62; ...@INESS  as in CLOUDY --&#62; CLOUDINESS 
523        if # .ne. Y, or @ = A, E, I, O, or U, 
524                ...@# --&#62; ...@#NESS  as in LATE --&#62; LATENESS 
525                                or GRAY --&#62; GRAYNESS 
526<P> 
527"M" FLAG: 
528        ... --&#62; ...'S  as in DOG --&#62; DOG'S 
529<P> 
530Note:    The  existence of a flag on a root word in the directory is not by 
531itself sufficient to cause SPELL to recognize the  indicated  word  ending. 
532If there is more than one root for which a flag will indicate a given word, 
533only  one  of the roots is the correct one for which the flag is effective; 
534generally it is the longest root.  For example, the "D" rule  implies  that 
535either PASS or PASSE, with a "D" flag, will yield PASSED.  The flag must be 
536on  PASSE;  it  will  be  ineffective on PASS.  This is because, when SPELL 
537encounters the word PASSED and fails to  find  it  in  its  dictionary,  it 
538strips off the "D" and looks up PASSE.  Upon finding PASSE, it then accepts 
539PASSED  if  and  only if PASSE has the "D" flag.  Only if the word PASSE is 
540not in the main dictionary at all does the program strip off  the  "E"  and 
541search  for PASS. 
542<P> 
543Therefore, never install a flag by hand.  Instead, just add complete 
544new words to the dictionary file, then use the build program with the 
545options '-a -r' to replace as many roots with flags as possible. 
546<P> 
547<H2><A NAME="SEC20" HREF="ispell_toc.html#SEC20">Where it came from</A></H2> 
548<P> 
549I first came across ispell on TOPS-20 systems at MIT.  I tracked it 
550down to ITS where I found the PDP-10 assembly program.  It appeared 
551that it had been in use at the MIT-AI lab since at least the late 
5521970's.  I think it case from California before then. 
553<P> 
554I wrote the first C implementation in the spring of 1983, mostly 
555working from the ITS INFO file. 
556<P> 
557The present version was created in early 1988, and was motivated by 
558the desire to make it run on 80286's, and to provide a better interface 
559for GNU EMACS. 
560<P> 
561There is another widely distributed version of ispell, which was forked 
562from my 1983 version and has a different set of features and clever 
563extensions.  It is available from the directory /u/public/ispell at 
564celray.cs.yale.edu. 
565<P> 
566People who have contributed to various versions of ispell include: Walt 
567Buehring, Mark Davies, Geoff Kuenning, Rober McQueer, Ashwin Ram, Greg 
568Schaffer, Perry Smith, Ken Stevens, and Andrew Vignaux. 
569<P> 
570Pace Willisson <BR> 
571pace@ai.mit.edu  pace@hx.lcs.mit.edu <BR> 
572(617) 625--3452 
573<P> 
574<P>Go to the <A HREF="ispell_1.html">previous</A> section.<P>
575