Section 26: Index to the rest of the tutorial The remainder of the tutorial can be perused at your leisure. Simply find the topic of interest in the following list, and {/Section xx:/^M} to get to the appropriate section. (Remember that ^M means the return key) The material in the following sections is not necessarily in a bottom up order. It should be fairly obvious that if a section mentions something with which you are not familiar, say, buffers, you might {/buffer/^M} followed by several {n} to do a keyword search of the file for more details on that item. Another point to remember is that commands are surrounded by curly-braces and can therefore be found rather easily. To see where, say, the X command is used try {/{X}/^M}. Subsequent {n} will show you other places the command was used. We have tried to maintain the convention of placing the command letter surrounded by curly-braces on the section line where that command is mentioned. Finally, you should have enough 'savvy' at this point to be able to do your own experimentation with commands without too much hand-holding on the part of the tutorial. Experimentation is the best way to learn the effects of the commands. Section Topic - description ------- ------------------- (Sections 1 through 25 are located in the file vi.beginner.) 1 introduction: {^F} {ZZ} 2 introduction (con't) and positioning: {^F} {^B} 3 introduction (con't) and positioning: {^F} {^B} 4 positioning: {^F} {^B} ^M (return key) 5 quitting: {:q!} ^M key 6 marking, cursor and screen positioning: {m} {G} {'} {z} 7 marking, cursor and screen positioning: {m} {G} {'} {z} 8 marking, cursor and screen positioning: {z} {m} {'} 9 marking and positioning: {m} {''} 10 line positioning: {^M} {-} 11 scrolling with {^M} 12 scrolling with {-} and screen adjustment {z} 13 notes on use of tutorial 14 other scrolling and postioning commands: {^E} {^Y} {^D} {^U} 15 searching: {/ .. /^M} 16 searching: {? .. ?^M} {n} (in search strings ^ $) 17 searching: \ and magic-characters in search strings 18 colon commands, exiting: {:} {ZZ} 19 screen positioning: {H} {M} {L} 20 character positioning: {w} {b} {0} {W} {B} {e} {E} {'} {`} 21 cursor positioning: {l} {k} {j} {h} 22 adding text: {i} {a} {I} {A} {o} {O} ^[ (escape key) 23 character manipulation: {f} {x} {X} {w} {l} {r} {R} {s} {S} {J} 24 undo: {u} {U} 25 review (The following sections are in this file.) 26 Index to the rest of the tutorial ******** YOU ARE HERE ******* 27 discussion of repeat counts and the repeat command: {.} 28 more on low-level character motions: {t} {T} {|} 29 advanced correction operators: {d} {c} 30 updating the screen: {^R} 31 text buffers: {"} 32 rearranging and duplicating text: {p} {P} {y} {Y} 33 recovering lost lines 34 advanced file manipulation with vi 34.1 more than one file at a time: {:n} 34.2 reading files and command output: {:r} 34.3 invoking vi from within vi: {:e} {:vi} 34.4 escaping to a shell: {:sh} {:!} 34.5 writing parts of a file: {:w} 34.6 filtering portions of text: {!} 35 advanced searching: magic patterns 36 advanced substitution: {:s} 37 advanced line addressing: {:p} {:g} {:v} 38 higher level text objects and nroff: ( ) { } [[ ]] 39 more about inserting text 40 more on operators: {d} {c} {<} {>} {!} {=} {y} 41 abbreviations: {:ab} 42 vi's relationship with the ex editor: {:} 43 vi on hardcopy terminals and dumb terminals: open mode 44 options: {:set} {setenv EXINIT} 44.1 autoindent 44.2 autoprint 44.3 autowrite 44.4 beautify 44.5 directory 44.6 edcompatible 44.7 errorbells 44.8 hardtabs 44.9 ignorecase 44.10 lisp 44.11 list 44.12 magic 44.13 mesg 44.14 number 44.15 open 44.16 optimize 44.17 paragraphs 44.18 prompt 44.19 readonly 44.20 redraw 44.21 remap 44.22 report 44.23 scroll 44.24 sections 44.25 shell 44.26 shiftwidth 44.27 showmatch 44.28 slowopen 44.29 tabstop 44.30 tags 44.31 taglength 44.32 term 44.33 terse 44.34 timeout 44.35 ttytype 44.36 warn 44.37 window 44.38 wrapscan 44.39 wrapmargin 44.40 writeany 44.41 w300, w1200, w9600 Section 27: repetition counts and the repeat command {.} Most vi commands will use a preceding count to affect their behavior in some way. We have already seen how {3x} deletes three characters, and {22G} moves us to line 22 of the file. For almost all of the commands, one can survive by thinking of these leading numbers as a 'repeat count' specifying that the command is to be repeated so many number of times. Other commands use the repeat count slightly differently, like the {G} command which use it as a line number. For example: {3^D} means scroll down in the file three lines. Subsequent {^D} OR {^U} will scroll only three lines in their respective directions! {3z^M} says put line three of the file at the top of the screen, while {3z.} says put line three as close to the middle of the screen as possible. {50|} moves the cursor to column fifty in the current line. {3^F} says move forward 3 screenfulls. This is a repetition count. The documents advertise that {3^B} should move BACK three screenfulls, but I can't get it to work. Position the cursor on some text and try {3r.}. This replaces three characters with '...'. However, {3s.....^[} is the same as {3xi.....^[}. Try {10a+----^[}. A very useful instance of a repetition count is one given to the '.' command, which repeats the last 'change' command. If you {dw} and then {3.}, you will delete first one and then three words. You can then delete two more words with {2.}. If you {3dw}, you will delete three words. A subsequent {.} will delete three more words. But a subsequent {2.} will delete only two words, not three times two words. Caveat: The author has noticed that any repetition count with {^B} will NOT work: indeed, if you are at the end of your file and try {3^B} sufficiently often, the editor will hang you in an infinite loop. Please don't try it: take my word for it. Section 28: {t} {T} {|} Position the cursor on line 13 below: Line 13: Four score and seven years ago, our forefathers brought ... Note that {fv} moves the cursor on/over the 'v' in 'seven'. Do a {0} to return to the beginning of the line and try a {tv}. The cursor is now on/over the first 'e' in 'seven'. The {f} command finds the next occurrence of the specified letter and moves the cursor to it. The {t} command finds the specified letter and moves the cursor to the character immediately preceding it. {T} searches backwards, as does {F}. Now try {60|}: the cursor is now on the 'o' in 'brought', which is the sixtieth character on the line. Section 29: {d} {c} Due to their complexity we have delayed discussion of two of the most powerful operators in vi until now. Effective use of these operators requires more explanation than was deemed appropriate for the first half of the tutorial. {d} and {c} are called operators instead of commands because they consist of three parts: a count specification or a buffer specification (see section #BUFFERS), the {d} or {c}, and the object or range description. We will not discuss buffers at this stage, but will limit ourselves to count specifications. Examples speak louder than words: position the cursor at the beginning of line 14: Line 14: Euclid alone has looked on beauty bear. Obviously, there is something wrong with this quotation. Type {2fb} to position the cursor on the 'b' of 'bear'. Now, type {cwbare^[} and observe the results. The {cw} specifies that the change command {c} is to operate on a word object. More accurately, it specifies that the range of the change command includes the next word. Position the cursor on the period in Line 14. (one way is to use {f.}) Now, type {cbbeast^[}. This specifies the range of the change command to be the previous word (the 'b' reminiscent of the {b} command). If we had wished to delete the word rather than change it, we would have used the {d} operator, rather than the {c} operator. Position the cursor at the beginning of the line with {0}. Type {d/look/^M}. The search string specified the range of the delete. Everything UP TO the word 'looking' was deleted from the line. In general, almost any command that would move the cursor will specify a range for these commands. The most confusing exception to this rule is when {dd} or {cc} is entered: they refer to the whole line. Following is a summary of the suffixes (suffices? suffici?) and the ranges they specify: suffix will delete{d}/change{c} ------ ------------------------ ^[ cancels the command w the word to the right of the cursor W ditto, but ignoring punctuation b the word to the left of the cursor B ditto, but ignoring punctuation e see below. E ditto (space) a character $ to the end of the line ^ to the beginning of the line / .. / up to, but not including, the string ? .. ? back to and including the string fc up to and including the occurrence of c Fc back to and including the occurrence of c tc up to but not including the occurrence of c Tc back to but not including the occurrence of c ^M TWO lines (that's right: two) (number)^M that many lines plus one (number)G up to and including line (number) ( the previous sentence if you are at the beginning of the current sentence, or the current sentence up to where you are if you are not at the beginning of the current sentence. Here, 'sentence' refers to the intuitive notion of an English sentence, ending with '!', '?', or '.' and followed by an end of line or two spaces. ) the rest of the current sentence { analogous to '(', but in reference to paragraphs: sections of text surrounded by blank lines } analogous to ')', but in reference to paragraphs [[ analogous to '(', but in reference to sections ]] analogous to ')', but in reference to sections H the first line on the screen M the middle line on the screen L the last line on the screen 3L through the third line from the bottom of the screen ^F forward a screenful ^B backward a screenful : : etc. etc. etc. This list is not exhaustive, but it should be sufficient to get the idea across: after the {c} or {d} operator, you can specify a range with another move-the-cursor command, and that is the region of text over which the command will be effective. Section 30: updating the screen {^R} Vi tries to be very intelligent about the type of terminal you are working on and tries to use the in-terminal computing power (if any) of your terminal. Also if the terminal is running at a low baud rate (say 1200 or below), vi sets various parameters to make things easier for you. For example, if you were running on a 300 baud terminal (that's 30 characters per second transmission rate) not all 24 lines of the screen would be used by vi. In addition, there is a large portion of the editor keeping track of what your screen currently looks like, and what it would look like after a command has been executed. Vi then compares the two, and updates only those portions of the screen that have changed. Furthermore, some of you may have noticed (it depends on your terminal) that deleting lines or changing large portions of text may leave some lines on the screen looking like: @ meaning that this line of the screen does not correspond to any line in your file. It would cost more to update the line than to leave it blank for the moment. If you would like to see your screen fully up-to-date with the contents of your file, type {^R}. To see it in action, delete several lines with {5dd}, type {^R}, and then type {u} to get the lines back. Here is as good a place as any to mention that if the editor is displaying the end of your file, there may be lines on the screen that look like: ~ indicating that that screen line would not be affected by {^R}. These lines simply indicate the end of the file. Section 31: text buffers {"} Vi gives you the ability to store text away in "buffers". This feature is very convenient for moving text around in your file. There are a total of thirty- five buffers available in vi. There is the "unnamed" buffer that is used by all commands that delete text, including the change operator {c}, the substitute and replace commands {s} and {r}, as well as the delete operator {d} and delete commands {x} and {X}. This buffer is filled each time any of these commands are used. However, the undo command {u} has no effect on the unnamed buffer. There are twenty-six buffers named 'a' through 'z' which are available for the user. If the name of the buffer is capitalized, then the buffer is not overwritten but appended to. For example, the command {"qdd} will delete one line and store that line in the 'q' buffer, destroying the previous contents of the buffer. However, {"Qdd} will delete one line of text and append that line to the current contents of the 'q' buffer. Finally, there are nine buffers named '1' through '9' in which the last nine deletes are stored. Buffer 1 is the default buffer for the modify commands and is sometimes called the unnamed buffer. To reference a specific buffer, use the double-quote command {"} followed by the name of the buffer. The next two sections show how buffers can be used to advantage. Section 32: rearranging and duplicating text: {y} {Y} {p} {P} Position yourself on line 15 below and {z^M}: Line 15: A tree as lovely as a poem ... Line 16: I think that I shall never see Type {dd}. Line 15 has disappeared and been replaced with the empty line (one with the single character @ on it) or (again depending on your terminal) Line 16 has moved up and taken its place. We could recover Line 15 with an undo {u} but that would simply return it to its original location. Obviously, the two lines are reversed, so we want to put line 15 AFTER line 16. This is simply done with the put command {p}, which you should type now. What has happened is that {dd} put Line 15 into the unnamed buffer, and the {p} command retrieved the line from the unnamed buffer. Now type {u} and observe that Line 15 disappears again (the put was undone without affecting the unnamed buffer). Type {P} and see that the capital {P} puts the line BEFORE the cursor. To get Line 15 where it belongs again type {dd}{p}. Also in Line 15 note that the words 'tree' and 'poem' are reversed. Using the unnamed buffer again: {ft}{dw}{ma}{fp}{P}{w}{dw}{`aP} will set things aright (note the use of the reverse quote). The put commands {p} and {P} do not affect the contents of the buffer. Therefore, multiple {p} or {P} will put multiple copies of the unnamed buffer into your file. Experiment with {d} and {p} on words, paragraphs, etc. Whatever {d} deletes, {p} can put. Position the cursor on Line 17 and {z^M}: Line 17: interest apple cat elephant boy dog girl hay farmer Our task is to alphabetize the words on line 17. With the named buffers (and a contrived example) it is quite easy: {"idw}{"adw}{"cdw}{"edw}{"bdw}{"ddw}{"gdw}{"hdw}{"fdw} stores each of the words in the named buffer corresponding to the first letter of each of the words ('interest' goes in buffer "i, 'apple' goes in buffer "a, etc.). Now to put the words in order type: {"ap$}{"bp$}{"cp$}{"dp$}{"ep$}{"fp$}{"gp$}{"hp$}{"ip$} Notice that, because 'farmer' was at the end of the line, {dw} did not include a space after it, and that, therefore, there is no space between 'farmer' and 'girl'. This is corrected with {Fg}{i ^[}. This example could have been done just as easily with lines as with words. You do not have to delete the text in order to put it into a buffer. If all you wish to do is to copy the text somewhere else, don't use {d}, rather use the yank commands {y} or {Y}. {y} is like {d} and {c} - an operator rather than a command. It, too, takes a buffer specification and a range specification. Therefore, instead of {dw}{P} to load the unnamed buffer with a word without deleting the word, use {yw} (yank a word). {Y} is designed yank lines, and not arbitrary ranges. That is, {Y} is equivalent to {yy} (remember that operators doubled means the current line), and {3Y} is equivalent to {3yy}. If the text you yank or modify forms a part of a line, or is an object such as a sentence which partially spans more than one line, then when you put the text back, it will be placed after the cursor (or before if you use {P}). If the yanked text forms whole lines, they will be put back as whole lines, without changing the current line. In this case, the put acts much like the {o} or {O} command. The named buffers "a through "z are not affected by changing edit files. However, the unnamed buffer is lost when you change files, so to move text from one file to another you should use a named buffer. Section 33: recovering lost lines Vi also keeps track of the last nine deletes, whether you ask for it or not. This is very convenient if you would like to recover some text that was accidentally deleted or modified. Position the cursor on line 18 following, and {z^M}. Line 18: line 1 Line 19: line 2 Line 20: line 3 Line 21: line 4 Line 22: line 5 Line 23: line 6 Line 24: line 7 Line 25: line 8 Line 26: line 9 Type {dd} nine times: now don't cheat with {9dd}! That is totally different. The command {"1p} will retrieve the last delete. Furthermore, when the numbered buffers are used, the repeat-command command {.} will increment the buffer numbers before executing, so that subsequent {.} will recover all nine of the deleted lines, albeit in reverse order. If you would like to review the last nine deletes without affecting the buffers or your file, do an undo {u} after each put {p} and {.}: {"1p}{u}{.}{u}{.}{u}{.}{u}{.}{u}{.}{u}{.}{u}{.}{u}{.} will show you all the buffers and leave them and your file intact. If you had cheated above and deleted the nine lines with {9dd}, all nine lines would have been stored in both the unnamed buffer and in buffer number 1. (Obviously, buffer number 1 IS the unnamed buffer and is just the default buffer for the modify commands.) Section 34: advanced file manipulation: {:r} {:e} {:n} {:w} {!} {:!} We've already looked at writing out the file you are editing with the {:w} command. Now let's look at some other vi commands to make editing more efficient. Section 34.1: more than one file at a time {:n} {:args} Many times you will want to edit more than one file in an editing session. Instead of entering vi and editing the first file, exiting, entering vi and editing the second, etc., vi will allow you to specify ALL files that you wish to edit on the invocation line. Therefore, if you wanted to edit file1 and file2: % vi file1 file2 will set up file1 for editing. When you are done editing file one, write it out {:w^M} and then type {:n^M} to get the next file on the list. On large programming projects with many source files, it is often convenient just to specify all source files with, say: % vi *.c If {:n^M} brings in a file that does not need any editing, another {:n^M} will bring in the next file. If you have made changes to the first file, but decide to discard these changes and proceed to the next file, {:n!^M} forces the editor to discard the current contents of the editor. You can specify a new list of files after {:n}; e.g., {:n f1 f2 f3^M}. This will replace the current list of files (if any). You can see the current list of files being edited with {:args^M}. Section 34.2: reading files and command output: {:r} Typing {:r fname^M} will read the contents of file fname into the editor and put the contents AFTER the cursor line. Typing {:r !cmd^M} will read the output of the command cmd and place that output after the cursor line. Section 34.3: invoking vi from within vi: {:e} {:vi} To edit another file not mentioned on the invocation line, type {:e filename^M} or {:vi filename^M}. If you wish to discard the changes to the current file, use the exclamation point after the command, e.g. {:e! filename^M}. Section 34.4: escaping to a shell: {:sh} {:!} {^Z} Occasionally, it is useful to interrupt the current editing session to perform a UNIX task. However, there is no need to write the current file out, exit the editor, perform the task, and then reinvoke the editor on the same file. One thing to do is to spin off another process. If there are several UNIX commands you will need to execute, simply create another shell with {:sh^M}. At this point, the editor is put to sleep and will be reawakened when you log out of the shell. If it is a single command that you want to execute, type {:!cmd^M}, where cmd is the command that you wish to run. The output of the command will come to the terminal as normal, and will not be made part of your file. The message "[Hit return to continue]" will be displayed by vi after the command is finished. Hitting return will then repaint the screen. Typing another {:!cmd^M} at this point is also acceptable. However, there is a quicker, easier way: type {^Z}. Now this is a little tricky, but hang in there. When you logged into UNIX, the first program you began communicating with was a program that is called a "shell" (i.e. it 'lays over' the operating system protecting you from it, sort of like a considerate porcupine). When you got your first prompt on the terminal (probably a '%' character) this was the shell telling you to type your first command. When you typed {vi filename} for some file, the shell did not go away, it just went to sleep. The shell is now the parent of vi. When you type {^Z} the editor goes to sleep, the shell wakes up and says "you rang?" in the form of another prompt (probably '%'). At this point you are talking to the shell again and you can do anything that you could before including edit another file! (The only thing you can't do is log out: you will get the message "There are stopped jobs.") When your business with the shell is done, type {fg} for 'foreground' and the last process which you ^Z'd out of will be reawakened and the shell will go back to sleep. I will refer you to the documentation for the Berkeley shell 'csh' for more information on this useful capability. Section 34.5: writing parts of a file: {:w} The {:w} command will accept a range specifier that will then write only a selected range of lines to a file. To write this section to a file, position the cursor on the section line (e.g. {/^Section 34.5:/^M}) and {z^M}. Now type {^G} to find out the line number (it will be something like "line 513"). Now {/^Section 34.6:/-1^M} to find the last line of this section, and {^G} to find its line number (it will be something like 542). To write out this section of text by itself to a separate file which we will call "sepfile", type {:510,542w sepfile^M}. If sepfile already exists, you will have to use the exclamation point: {:1147,1168w! sepfile^M} or write to a different, non- existent file. {:!cat sepfile^M} will display the file just written, and it should be the contents of this section. There is an alternate method of determining the line numbers for the write. {:set number^M} will repaint the screen with each line numbered. When the file is written and the numbers no longer needed, {:set nonumber^M} will remove the numbers, and {^R} will adjust the screen. Or, if you remember your earlier lessons about marking lines of text, mark the beginning and ending lines. Suppose we had used {ma} to mark the first line of the section and {mb} to mark the last. Then the command {:'a,'bw sepfile^M} will write the section into "sepfile". In general, you can replace a line number with the 'name' of a marked line (a single-quote followed by the letter used to mark the line) Section 34.6: filtering portions of text: {!} {!} is an operator like {c} and {d}. That is, it consists of a repetition count, {!}, and a range specifier. Once the {!} operator is entered in its entirety, a prompt will be given at the bottom of the screen for a UNIX command. The text specified by the {!} operator is then deleted and passed/filtered/piped to the UNIX command you type. The output of the UNIX command is then placed in your file. For example, place the cursor at the beginning of the following line and {z^M}: ls -l vi.tutorial ********* marks the bottom of the output from the ls command ********** Now type {!!csh^M}. The line will be replaced with the output from the ls command. The {u} command works on {!}, also. Here is an extended exercise to display some of these capabilities. When this tutorial was prepared, certain auxiliary programs were created to aid in its development. Of major concern was the formatting of sections of the tutorial to fit on a single screen, particularly the first few sections. What was needed was a vi command that would 'format' a paragraph; that is, fill out lines with as many words as would fit in eighty columns. There is no such vi command. Therefore, another method had to be found. Of course, nroff was designed to do text formatting. However, it produces a 'page'; meaning that there may be many blank lines at the end of a formatted paragraph from nroff. The awk program was used to strip these blank lines from the output from nroff. Below are the two files used for this purpose: I refer you to documentation on nroff and awk for a full explanation of their function. Position the cursor on the next line and {z^M}. ******** contents of file f ********** # nroff -i form.mac | awk "length != 0 { print }" ***** contents of file form.mac ****** .na .nh .ll 79 .ec .c2 .cc ************************************** Determine the line numbers of the two lines of file f. They should be something like 574 and 575, although you better double check: this file is under constant revision and the line numbers may change inadvertently. Then {:574,575w f^M}. Do the same for the lines of file form.mac. They will be approximately 577 and 582. Then {:577,582w form.mac^M}. File f must have execute privileges as a shell file: {:!chmod 744 f^M}. Observe that this paragraph is rather ratty in appearance. With our newly created files we can clean it up dramatically. Position the cursor at the beginning of this paragraph and type the following sequence of characters (note that we must abandon temporarily our convention of curly braces since the command itself contains a curly brace - we will use square brackets for the nonce): [!}f^M]. Here is a brief explanation of what has happened. By typing [!}f^M] we specified that the paragraph (all text between the cursor and the first blank line) will be removed from the edit file and piped to a UNIX program called "f". This is a shell command file that we have created. This shell file runs nroff, pipes its output to awk to remove blank lines, and the output from awk is then read back into our file in the place of the old, ratty paragraph. The file form.mac is a list of commands to nroff to get it to produce paragraphs to our taste (the right margin is not justified, the line is 79 characters long, words are not hyphenated, and three nroff characters are renamed to avoid conflict: note that in this file, the {^G} you see there is vi's display of the control-G character, and not the two separate characters ^ up-arrow and G upper-case g). This example was created before the existence of the fmt program. I now type [!}fmt^M] to get the same effect much faster. Actually, I don't type those six keys each time: I have an abbreviation (which see). Section 35: searching with magic patterns The documentation available for "magic patterns" (i.e. regular expressions) is very scanty. The following should explain this possibly very confusing feature of the editor. This section assumes that the magic option is on. To make sure, you might want to type {:set magic^M}. By "magic pattern" we mean a general description of a piece of text that the editor attempts to find during a search. Most search patterns consist of strings of characters that must be matched exactly, e.g. {/card/^M} searches for a specific string of four characters. Let us suppose that you have discovered that you consistently have mistyped this simple word as either ccrd or czrd (this is not so far-fetched for touch typists). You could {/ccrd/^M} and {n} until there are no more of this spelling, followed by {/czrd/^M} and {n} until there are no more of these. Or you could {/c.rd/^M} and catch all of them on the first pass. Try typing {/c.rd/^M} followed by several {n} and observe the effect. Line 27: card cord curd ceard When '.' is used in a search string, it has the effect of matching any single character. The character '^' (up-arrow) used at the beginning of a search string means the beginning of the line. {/^Line 27/^M} will find the example line above, while {/Line 27/^M} will find an occurrence of this string anywhere in the line. Similarly, {/ the$/^M} will find all occurrences of the word 'the' occurring at the end of a line. There are several of them in this file. Note that {:set nomagic^M} will turn off the special meaning of these magic characters EXCEPT for '^' and '$' which retain their special meanings at the beginning and end of a search string. Within the search string they hold no special meaning. Try {/\/ the$\//^M} and note that the dollar-sign is not the last character in the search string. Let the dollar-sign be the last character in the search string, as in {/\/ the$/^M} and observe the result. Observe the result of {/back.*file/^M}. This command, followed by sufficient {n}, will show you all lines in the file that contain both the words 'back' and 'file' on the same line. The '*' magic character specifies that the previous regular expression (the '.' in our example) is to be repeatedly matched zero or more times. In our example we specified that the words 'back' and 'file' must appear on the same line (they may be parts of words such as 'backwards' or 'workfile') separated by any number (including zero) of characters. We could have specified that 'back' and 'file' are to be words by themselves by using the magic sequences '\<' or '\>'. E.g. {/\<back\>.*\<file\>/^M}. The sequence '\<' specifies that this point of the search string must match the beginning of a word, while '\>' specifies a match at the end of a word. By surrounding a string with these characters we have specified that they must be words. To find all words that begin with an 'l' or a 'w', followed by an 'a' or an 'e', and ending in 'ing', try {/\<[lw][ea][a-z]*ing\>/^M}. This will match words like 'learning', 'warning', and 'leading'. The '[..]' notation matches exactly ONE character. The character matched will be one of the characters enclosed in the square brackets. The characters may be specified individually as in [abcd] or a '-' may be used to specify a range of characters as in [a-d]. That is, [az] will match the letter 'a' OR the letter 'z', while [a-z] will match any of the lower case letters from 'a' through 'z'. If you would like to match either an 'a', a '-', or a 'z', then the '-' must be escaped: [a\-z] will match ONE of the three characters 'a', '-', or 'z'. If you wish to find all Capitalized words, try {/\<[A-Z][a-z]*\>/^M}. The following will find all character sequences that do NOT begin with an uncapitalized letter by applying a special meaning to the '^' character in square brackets: {/\<[^a-z][a-z]*\>/^M}. When '^' is the first character of a square-bracket expression, it specifies "all but these characters". (No one claimed vi was consistent.) To find all variable names (the first character is alphabetic, the remaining characters are alphanumeric): try {/\<[A-Za-z][A-Za-z0-9]*\>/^M}. In summary, here are the primitives for building regular expressions: ^ at beginning of pattern, matches beginning of line $ at end of pattern, matches end of line . matches any single character \< matches the beginning of a word \> matches the end of a word [str] matches any single character in str [^str] matches any single character NOT in str [x-y] matches any character in the ASCII range between x and y * matches any number (including zero) of the preceding pattern Section 36: advanced substitution: {:s} The straightforward colon-substitute command looks like the substitute command of most line-oriented editors. Indeed, vi is nothing more than a superstructure on the line-oriented editor ex and the colon commands are simply a way of accessing commands within ex (see section #EX). This gives us a lot of global file processing not usually found in visual oriented editors. The colon-substitute command looks like: {:s/ .. / .. /^M} and will find the pattern specified after the first slash (this is called the search pattern), and replace it with the pattern specified after the second slash (called, obviously enough, the replacement pattern). E.g. position the cursor on line 28 below and {:s/esample/example/^M}: Line 28: This is an esample. The {u} and {U} commands work for {:s}. The first pattern (the search pattern) may be a regular expression just as for the search command (after all, it IS a search, albeit limited to the current line). Do an {u} on the above line, and try the following substitute, which will do almost the same thing: {:s/s[^ ]/x/^M}. Better undo it with {u}. The first pattern {s[^ ]} matches an 's' NOT followed by a blank: the search therefore ignores the 's'es in 'This' and 'is'. However, the character matched by {[^ ]} must appear in the replacement pattern. But, in general, we do not know what that character is! (In this particular example we obviously do, but more complicated examples will follow.) Therefore, vi (really ex) has a duplication mechanism to copy patterns matched in the search string into the replacement string. Line 29 below is a copy of line 28 above so you can adjust your screen. Line 29: This is an esample. In general, you can nest parts of the search pattern in \( .. \) and refer to it in the replacement pattern as \n, where n is a digit. The problem outlined in the previous paragraph is solved with {:s/s\([^ ]\)/x\1/^M}: try it. Here \1 refers to the first pattern grouping \( .. \) in the search string. Obviously, for a single line, this is rather tedious. Where it becomes powerful, if not necessary, is in colon-substitutes that cover a range of lines. (See the next section for a particularly comprehensive example.) If the entire character sequence matched by the search pattern is needed in the replacement pattern, then the unescaped character '&' can be used. On Line 29 above, try {:s/an e.ample/not &/^M}. If another line is to have the word 'not' prepended to a pattern, then '~' can save you from re-typing the replacement pattern. E.g. {:s/some pattern/~/^M} after the previous example would be equivalent to {:s/some pattern/not &/^M}. One other useful replacement pattern allows you to change the case of individual letters. The sequences {\u} and {\l} cause the immediately following character in the replacement to be converted to upper- or lower-case, respectively, if this character is a letter. The sequences {\U} and {\L} turn such conversion on, either until {\E} or {\e} is encountered, or until the end of the replacement pattern. For example, position the cursor on a line: pick a line, any line. Type {:s/.*/\U&/^M} and observe the result. You can undo it with {u}. The search pattern may actually match more than once on a single line. However, only the first pattern is substituted. If you would like ALL patterns matched on the line to be substituted, append a 'g' after the replacement pattern: {:s/123/456/g^M} will substitute EVERY occurrence on the line of 123 with 456. Section 37: advanced line addressing: {:p} {:g} {:v} Ex (available through the colon command in vi) offers several methods for specifying the lines on which a set of commands will act. For example, if you would like to see lines 50 through 100 of your file: {:50,100p^M} will display them, wait for you to [Hit return to continue], and leave you on line 100. Obviously, it would be easier just to do {100G} from within vi. But what if you would like to make changes to just those lines? Then the addressing is important and powerful. Line 30: This is a text. Line 31: Here is another text. Line 32: One more text line. The lines above contain a typing error that the author of this tutorial tends to make every time he attempts to type the word 'test'. To change all of these 'text's into 'test's, try the following: {:/^Line 30/,/^Line 32/s/text/test/^M}. This finds the beginning and end of the portion of text to be changed, and limits the substitution to each of the lines in that range. The {u} command applies to ALL of the substitutions as a group. This provides a mechanism for powerful text manipulations. And very complicated examples. Line 33: This test is a. Line 34: Here test is another. Line 35: One line more test. The above three lines have the second word out of order. The following command string will put things right. Be very careful when typing this: it is very long, full of special characters, and easy to mess up. You may want to consider reading the following section to understand it before trying the experiment. Don't worry about messing up the rest of the file, though: the address range is specified. {:/^Line 33/,/^Line 35/s/\([^:]*\): \([^ ]*\) \([^ ]*\) \([^.]*\)/\1: \2 \4 \3/^M} There are several things to note about this command string. First of all, the range of the substitute was limited by the address specification {/^Line 33/,/^Line 35/^M}. It might have been simpler to do {:set number^M} to see the line numbers directly, and then, in place of the two searches, typed the line numbers, e.g. {1396,1398}. Or to mark the lines with {ma} and {mb} and use {'a,'b}. Then follows the substitute pattern itself. To make it easier to understand what the substitute is doing, the command is duplicated below with the various patterns named for easier reference: s/\([^:]*\): \([^ ]*\) \([^ ]*\) \([^.]*\)/\1: \2 \4 \3/ |--\1---| |--\2---| |--\3---| |--\4---| |--------search pattern------------------|-replacement| |--pattern---| In overview, the substitute looks for a particular pattern made up of sub-patterns, which are named \1, \2, \3, and \4. These patterns are specified by stating what they are NOT. Pattern \1 is the sequence of characters that are NOT colons: in the search string, {[^:]} will match exactly one character that is not a colon, while appending the asterisk {[^:]*} specifies that the 'not a colon' pattern is to be repeated until no longer satisfied, and {\([^:]*\)} then gives the pattern its name, in this case \1. Outside of the specification of \1 comes {: }, specifying that the next two characters must be a colon followed by a blank. Patterns \2 and \3 are similar, specifying character sequences that are not blanks. Pattern \4 matches up to the period at the end of the line. The replacement pattern then consists of specifying the new order of the patterns. This is a particularly complicated example, perhaps the most complicated in this tutorial/reference. For our small examples, it is obviously tedious and error prone. For large files, however, it may be the most efficient way to make the desired modifications. (The reader is advised to look at the documentation for awk. This tool is very powerful and slightly simpler to use than vi for this kind of file manipulation. But, it is another command language to learn.) Many times, you will not want to operate on every line in a certain range. Rather you will want to make changes on lines that satisfy certain patterns; e.g. for every line that has the string 'NPS' on it, change 'NPS' to 'Naval Postgraduate School'. The {:g} addressing command was designed for this purpose. The example of this paragraph could be typed as {:g/NPS/s//Naval Postgraduate School/^M}. The general format of the command is {:g/(pattern)/cmds^M} and it works in the following way: all lines that match the pattern following the {:g} are 'tagged' in a special way. Then each of these lines have the commands following the pattern executed over them. Line 36: ABC rhino george farmer Dick jester lest Line 37: george farmer rhino lest jester ABC Line 38: rhino lest george Dick farmer ABC jester Type: {:g/^Line.*ABC/s/Dick/Harry Binswanger/|s/george farmer/gentleman george/p^M} There are several things of note here. First, lines 36, 37, and 38 above are tagged by the {:g}. Type {:g/^Line.*ABC/p^M} to verify this. Second, there are two substitutes on the same line separated by '|'. In general, any colon commands can be strung together with '|'. Third, both substitutes operate on all three lines, even though the first stubstitute works on only two of the lines (36 and 38). Fourth, the second substitute works on only two lines (36 and 37) and those are the two lines printed by the trailing 'p'. The {:v} command works similarly to the {:g} command, except that the sense of the test for 'tagging' the lines is reversed: all lines NOT matching the search pattern are tagged and operated on by the commands. Using {^V} to quote carriage return (see section 39) can be used in global substitutions to split two lines. For example, the command {:g/\. /s//.^V^M/g^M} will change your file so that each sentence is on a separate line. (Note that we have to 'escape' the '.', because '.' by itself matches any character. Our command says to find any line which contains a period followed by 2 spaces, and inserts a carriage return after the period.) Caveat: In some of the documentation for ex and vi you may find the comment to the effect that {\^M} can be used between commands following {:g}. The author of this tutorial has never gotten this to work and has crashed the editor trying. Section 38: higher level text objects and nroff: {(} {)} [{] [}] {[[} {]]} (Note: this section may be a little confusing because of our command notation. Using curly braces to surround command strings works fine as long as the command string does not contain any curly braces itself. However, the curly braces are legitimate commands in vi. Therefore, for any command sequence that contains curly braces, we will surround that sequence with SQUARE braces, as on the previous Section line.) In working with a document, particularly if using the text formatting programs nroff or troff, it is often advantageous to work in terms of sentences, paragraphs, and sections. The operations {(} and {)} move to the beginning of the previous and next sentences, respectively. Thus the command {d)} will delete the rest of the current sentence; likewise {d(} will delete the previous sentence if you are at the beginning of the current sentence, or, if you are not at the beginning of a sentence, it will delete the current sentence from the beginning up to where you are. A sentence is defined to end at a '.', '!', or '?' which is followed by either the end of a line, or by two spaces. Any number of closing ')', ']', '"', and ''' characters may appear after the '.', '!', or '?' before the spaces or end of line. Therefore, the {(} and {)} commands would recognize only one sentence in the following line, but two sentences on the second following line. Line 39: This is one sentence. Even though it looks like two. Line 40: This is two sentences. Because it has two spaces after the '.'. The operations [{] and [}] move over paragraphs and the operations {[[} and {]]} move over sections. A paragraph begins after each empty line, and also at each of a set of nroff paragraph macros. A section begins after each line with a form-feed ^L in the first column, and at each of a set of nroff section macros. When preparing a text file as input to nroff, you will probably be using a set of nroff macros to make the formatting specifications easier, or more to your taste. These macros are invoked by beginning a line with a period followed by the one or two letter macro name. Vi has been programmed to recognize these nroff macros, and if it doesn't recognize your particular macro you can use the {:set paragraphs} or {:set sections} commands so that it will. Section 39: more about inserting text There are a number of characters which you can use to make correnctions during input mode. These are summarized in the following table. ^H deletes the last input character ^W deletes the last input word (erase) same as ^H; each terminal can define its own erase character; for some it is ^H, for others it is the DELETE key, and for others it is '@'. (kill) deletes the input on this line; each terminal can define its own line-kill character; for some it is ^U, for others it is '@'; you will need to experiment on your terminal to find out what your line-kill and erase characters are. \ escapes a following ^H, (kill), and (erase) characters: i.e. this is how to put these characters in your file. ^[ escape key; ends insertion mode ^? the delete key; interrupts an insertion, terminating it abnormally. ^M the return key; starts a new line. ^D backtabs over the indentation set by the autoindent option 0^D backtabs over all indentation back to the beginning of the line ^^D (up-arrow followed by control-d)same as 0^D, except the indentation will be restored at the beginning of the next line. ^V quotes the next non-printing character into the file If you wish to type in your erase or kill character (say # or @ or ^U) then you must precede it with a \, just as you would do at the normal system command level. A more general way of typing non-printing characters into the file is to precede them with a ^V. The ^V echoes as a ^ character on which the cursor rests. This indicates that the editor expects you to type a control character and it will be inserted into the file at that point. There are a few exceptions to note. The implementation of the editor does not allow the null character ^@ to appear in files. Also the linefeed character ^J is used by the editor to separate lines in the file, so it cannot appear in the middle of a line. (Trying to insert a ^M into a file, or putting it in the replacement part of a substitution string will result in the matched line being split in two. This, in effect, is how to split lines by using a substitution.) You can insert any other character, however, if you wait for the editor to echo the ^ before you type the character. In fact, the editor will treat a following letter as a request for the corresponding control character. This is the only way to type ^S or ^Q, since the system normally uses them to suspend and resume output and never gives them to the editor to process. If you are using the autoindent option you can backtab over the indent which it supplies by typing a ^D. This backs up to the boundary specified by the shiftwidth option. This only works immediately after the supplied autoindent. When you are using the autoindent option you may wish to place a label at the left margin of a line. The way to do this easily is to type ^ (up-arrow) and then ^D. The editor will move the cursor to the left margin for one line, and restore the previous indent on the next. You can also type a 0 followed immediately by a ^D if you wish to kill all indentation and not have it resume on the next line. Section 40: more on operators: {d} {c} {<} {>} {!} {=} {y} Below is a non-exhaustive list of commands that can follow the operators to affect the range over which the operators will work. However, note that the operators {<}, {>}, {!}, and {=} do not operate on any object less than a line. Try {!w} and you will get a beep. To get the operator to work on just the current line, double it. E.g. {<<}. suffix will operate on ------ ------------------------ ^[ cancels the command w the word to the right of the cursor W ditto, but ignoring punctuation b the word to the left of the cursor B ditto, but ignoring punctuation e see below. E ditto (space) a character $ to the end of the line ^ to the beginning of the line / .. / up to, but not including, the string ? .. ? back to and including the string fc up to and including the occurrence of c Fc back to and including the occurrence of c tc up to but not including the occurrence of c Tc back to but not including the occurrence of c ^M TWO lines (that's right: two) (number)^M that many lines plus one (number)G up to and including line (number) ( the previous sentence if you are at the beginning of the current sentence, or the current sentence up to where you are if you are not at the beginning of the current sentence. Here, 'sentence' refers to the intuitive notion of an English sentence, ending with '!', '?', or '.' and followed by an end of line or two spaces. ) the rest of the current sentence { analogous to '(', but in reference to paragraphs: sections of text surrounded by blank lines } analogous to ')', but in reference to paragraphs [[ analogous to '(', but in reference to sections ]] analogous to ')', but in reference to sections H the first line on the screen M the middle line on the screen L the last line on the screen 3L through the third line from the bottom of the screen ^F forward a screenful ^B backward a screenful : : etc. etc. etc. This list is not exhaustive, but it should be sufficient to get the idea across: after the operator, you can specify a range with a move-the-cursor command, and that is the region of text over which the operator will be effective. Section 41: abbreviations: {:ab} When typing large documents you may find yourself typing a large phrase over and over. Vi gives you the ability to specify an abbreviation for a long string such that typing the abbreviation will automatically expand into the longer phrase. Type {:ab nps Naval Postgraduate School^M}. Now type: {iThis is to show off the nps's UNIX editor.^M^[} Section 42: vi's relationship with the ex editor: {:} Vi is actually one mode of editing within the editor ex. When you are running vi you can escape to the line oriented editor of ex by giving the command {Q}. All of the colon-commands which were introduced above are available in ex. Likewise, most ex commands can be invoked from vi using {:}. In rare instances, an internal error may occur in vi. In this case you will get a diagnostic and will be left in the command mode of ex. You can then save your work and quit if you wish by giving the command {x} after the colon prompt of ex. Or you can reenter vi (if you are brave) by giving ex the command {vi}. Section 43: vi on hardcopy terminals and dumb terminals: open mode (The author has not checked the following documentation for accuracy. It is abstracted from the Introduction to Vi Editing document.) If you are on a hardcopy terminal or a terminal which does not have a cursor which can move off the bottom line, you can still use the command set of vi, but in a different mode. When you give the vi command to UNIX, the editor will tell you that it is using open mode. This name comes from the open command in ex, which is used to get into the same mode. The only difference between visual mode (normal vi) and open mode is the way in which the text is displayed. In open mode the editor uses a single line window into the file, and moving backward and forward in the file causes new lines to be displayed, always below the current line. Two commands of vi work differently in open: {z} and {^R}. The {z} command does not take parameters, but rather draws a window of context around the current line and then returns you to the current line. If you are on a hardcopy terminal, the {^R} command will retype the current line. On such terminals, the editor normally uses two lines to represent the current line. The first line is a copy of the line as you started to edit it, and you work on the line below this line. When you delete characters, the editor types a number of \'s to show you the characters which are deleted. The editor also reprints the current line soon after such changes so that you can see what the line looks like again. It is sometimes useful to use this mode on very slow terminals which can support vi in the full screen mode. You can do this by entering ex and using an {open} command. ********************************************************************* Section 44: options: {:set} {setenv EXINIT} You will discover options as you need them. Do not worry about them very much on the first pass through this document. My advice is to glance through them, noting the ones that look interesting, ignoring the ones you don't understand, and try re-scanning them in a couple of weeks. If you decide that you have a favorite set of options and would like to change the default values for the editor, place a {setenv EXINIT} command in your .login file. When you are given an account under UNIX your directory has placed in it a file that is executed each time you log in. If one of the commands in this file sets the environment variable EXINIT to a string of vi commands, you can have many things done for you each time you invoke vi. For example, if you decide that you don't like tabstops placed every eight columns but prefer every four columns, and that you wish the editor to insert linefeeds for you when your typing gets you close to column 72, and you want autoindentation, then include the following line in your .login file: setenv EXINIT='set tabstop=4 wrapmargin=8 autoindent' or equivalently setenv EXINIT='se ts=4 wm=8 ai' Each time you bring up vi, this command will be executed and the options set. There are forty options in the vi/ex editor that the user can set for his/her own convenience. They are described in more detail in individual sections below. The section line will show the full spelling of the option name, the abbreviation, and the default value of the option. The text itself comes from the ex reference manual and is not the epitome of clarity. Section 44.1: {autoindent}, {ai} default: noai Can be used to ease the preparation of structured program text. At the beginning of each append, change or insert command or when a new line is opened or created by an append, change, insert, or substitute operation within open or visual mode, ex looks at the line being appended after, the first line changed or the line inserted before and calculates the amount of white space at the start of the line. It then aligns the cursor at the level of indentation so determined. If the user then types lines of text in, they will continue to be justified at the displayed indenting level. If more white space is typed at the beginning of a line, the following line will start aligned with the first non-white character of the previous line. To back the cursor up to the preceding tab stop one can hit {^D}. The tab stops going backwards are defined at multiples of the shiftwidth option. You cannot backspace over the indent, except by sending an end-of-file with a {^D}. A line with no characters added to it turns into a completely blank line (the white space provided for the autoindent is discarded). Also specially processed in this mode are lines beginning with an up-arrow `^' and immediately followed by a {^D}. This causes the input to be repositioned at the beginning of the line, but retaining the previous indent for the next line. Similarly, a `0' followed by a {^D} repositions at the beginning but without retaining the previous indent. Autoindent doesn't happen in global commands or when the input is not a terminal. Section 44.2: {autoprint}, {ap} default: ap Causes the current line to be printed after each delete, copy, join, move, substitute, t, undo or shift command. This has the same effect as supplying a trailing `p' to each such command. Autoprint is suppressed in globals, and only applies to the last of many commands on a line. Section 44.3: {autowrite}, {aw} default: noaw Causes the contents of the buffer to be written to the current file if you have modified it and give a next, rewind, stop, tag, or {!} command, or a control- up-arrow {^^} (switch files) or {^]} (tag goto) command in visual. Note, that the edit and ex commands do not autowrite. In each case, there is an equivalent way of switching when autowrite is set to avoid the autowrite ({edit} for next, rewind! for rewind, stop! for stop, tag! for tag, shell for {!}, and {:e #} and a {:ta!} command from within visual). Section 44.4: {beautify}, {bf} default: nobeautify Causes all control characters except tab ^I, newline ^M and form-feed ^L to be discarded from the input. A complaint is registered the first time a backspace character is discarded. Beautify does not apply to command input. Section 44.5: {directory}, {dir} default: dir=/tmp Specifies the directory in which ex places its buffer file. If this directory in not writable, then the editor will exit abruptly when it fails to be able to create its buffer there. Section 44.6: {edcompatible} default: noedcompatible Causes the presence or absence of g and c suffixes on substitute commands to be remembered, and to be toggled by repeating the suffices. The suffix r makes the substitution be as in the {~} command, instead of like {&}. [Author's note: this should not concern users of vi.] Section 44.7: {errorbells}, {eb} default: noeb Error messages are preceded by a bell. However, bell ringing in open and visual modes on errors is not suppressed by setting noeb. If possible the editor always places the error message in a standout mode of the terminal (such as inverse video) instead of ringing the bell. Section 44.8: {hardtabs}, {ht} default: ht=8 Gives the boundaries on which terminal hardware tabs are set (or on which the system expands tabs). Section 44.9: {ignorecase}, {ic} default: noic All upper case characters in the text are mapped to lower case in regular expression matching. In addition, all upper case characters in regular expressions are mapped to lower case except in character class specifications (that is, character in square brackets). Section 44.10: {lisp} default: nolisp Autoindent indents appropriately for lisp code, and the {(}, {)}, [{], [}], {[[}, and {]]} commands in open and visual modes are modified in a striaghtforward, intuitive fashion to have meaning for lisp. [Author's note: but don't ask me to define them precisely.] Section 44.11: {list} default: nolist All printed lines will be displayed (more) unambiguously, showing tabs as ^I and end-of-lines with `$'. This is the same as in the ex command {list}. Section 44.12: {magic} default: magic for {ex} and {vi}, nomagic for edit. If nomagic is set, the number of regular expression metacharacters is greatly reduced, with only up-arrow `^' and `$' having special effects. In addition the metacharacters `~' and `&' of the replacement pattern are treated as normal characters. All the normal metacharacters may be made magic when nomagic is set by preceding them with a `\'. [Author's note: In other words, if magic is set a back-slant turns the magic off for the following character, and if nomagic is set a back-slant turns the magic ON for the following character. And, no, we are not playing Dungeons and Dragons, although I think the writers of these option notes must have played it all the time.] Section 44.13: {mesg} default: mesg Causes write permission to be turned off to the terminal while you are in visual mode, if nomesg is set. [Author's note: I don't know if anyone could have made any one sentence paragraph more confusing than this one. What it says is: mesg allows people to write to you even if you are in visual or open mode; nomesg locks your terminal so they can't write to you and mess up your screen.] Section 44.14: {number, nu} default: nonumber Causes all output lines to be printed with their line numbers. In addition each input line will be prompted with its line number. Section 44.15: {open} default: open If {noopen}, the commands open and visual are not permitted. This is set for edit to prevent confusion resulting from accidental entry to open or visual mode. [Author's note: As you may have guessed by now, there are actually three editors available under Berkeley UNIX that are in reality the same program, ex, with different options set: ex itself, vi, and edit.] Section 44.16: {optimize, opt} default: optimize Throughput of text is expedited by setting the terminal to not do automatic carriage returns when printing more than one (logical) line of output, greatly speeding output on terminals without addressable cursors when text with leading white space is printed. [Author's note: I still don't know what this option does.] Section 44.17: {paragraphs, para} default: para=IPLPPPQPP LIbp Specifies the paragraphs for the [{] and [}] operations in open and visual. The pairs of characters in the option's value are the names of the nroff macros which start paragraphs. Section 44.18: {prompt} default: prompt Command mode input is prompted for with a `:'. [Author's note: Doesn't seem to have any effect on vi.] Section 44.19: {readonly}, {ro} default: noro, unless invoked with -R or insufficient privileges on file This option allows you to guarantee that you won't clobber your file by accident. You can set the option and writes will fail unless you use an `!' after the write. Commands such as {x}, {ZZ}, the autowrite option, and in general anything that writes is affected. This option is turned on if you invoke the editor with the -R flag. Section 44.20: {redraw} default: noredraw The editor simulates (using great amounts of output), an intelligent terminal on a dumb terminal (e.g. during insertions in visual the characters to the right of the cursor position are refreshed as each input character is typed). Useful only at very high baud rates, and should be used only if the system is not heavily loaded: you will notice the performance degradation yourself. Section 44.21: {remap} default: remap If on, macros are repeatedly tried until they are unchanged. For example, if o is mapped to O, and O is mapped to I, then if remap is set, o will map to I, but if noremap is set, it will map to O . Section 44.22: {report} default: report=5 for ex and vi, 2 for edit Specifies a threshold for feedback from commands. Any command which modifies more than the specified number of lines will provide feedback as to the scope of its changes. For commands such as global, open, undo, and visual which have potentially more far reaching scope, the net change in the number of lines in the buffer is presented at the end of the command, subject to this same threshold. Thus notification is suppressed during a global command on the individual commands performed. Section 44.23: {scroll} default: scroll=1/2 window Determines the number of logical lines scrolled when a {^D} is received from a terminal in command mode, and determines the number of lines printed by a command mode z command (double the value of scroll). [Author's note: Doesn't seem to affect {^D} and {z} in visual (vi) mode.] Section 44.24: sections {sections} default: sections=SHNHH HU Specifies the section macros from nroff for the {[[} and {]]} operations in open and visual. The pairs of characters in the options's value are the names of the macros which start paragraphs. Section 44.25: {shell}, {sh} default: sh=/bin/sh Gives the path name of the shell forked for the shell escape command `!', and by the shell command. The default is taken from SHELL in the environment, if present. [Editor's note: I would suggest that you place the following line in your .login file: setenv SHELL '/bin/csh' ] Section 44.26: {shiftwidth}, {sw} default: sw=8 Used in reverse tabbing with {^D} when using autoindent to append text, and used by the shift commands. Should probably be the same value as the tabstop option. Section 44.27: {showmatch}, {sm} default: nosm In open and visual mode, when a `)' or `}' is typed, if the matching `(' or `{' is on the screen, move the cursor to it for one second. Extremely useful with complicated nested expressions, or with lisp. Section 44.28: {slowopen}, {slow} default: terminal dependent Affects the display algorithm used in visual mode, holding off display updating during input of new text to improve throughput when the terminal in use is both slow and unintelligent. See "An Introduction to Display Editing with Vi" for more details. Section 44.29: {tabstop}, {ts} default: ts=8 The editor expands tabs ^I to tabstop boundaries in the display. Section 44.30: {taglength}, {tl} default: tl=0 Tags are not significant beyond this many characters. A value of zero (the default) means that all characters are significant. Section 44.31: {tags} default: tags=tags /usr/lib/tags A path of files to be used as tag files for the tag command. A requested tag is searched for in the specified files, sequentially. By default files called tags are searched for in the current directory and in /usr/lib (a master file for the entire system). [Author's note: The author of this tutorial has never used this option, nor seen it used. I'm not even sure I know what they are talking about.] Section 44.32: {term} default: from environment variable TERM The terminal type of the output device. Section 44.33: {terse} default: noterse Shorter error diagnostics are produced for the experienced user. Section 44.34: {timeout} default: timeout Causes macros to time out after one second. Turn it off and they will wait forever. This is useful if you want multi-character macros, but if your terminal sends escape sequences for arrow keys, it will be necessary to hit escape twice to get a beep. [Editor's note: Another paragraph which requires a cryptographer.] Section 44.35: ttytype [Editor's note: I have found no documentation for this option at all.] Section 44.36: {warn} default: warn Warn if there has been `[No write since last change]' before a `!' command escape. Section 44.37: {window} default: window=speed dependent The number of lines in a text window in the visual command. The default is 8 at slow speeds (600 baud or less), 16 at medium speed (1200 baud), and the full screen (minus one line) at higher speeds. Section 44.38: {wrapscan}, {ws} default: ws Searches using the regular expressions in addressing will wrap around past the end of the file. Section 44.39: {wrapmargin}, {wm} default: wm=0 Defines a margin for automatic wrapover of text during input in open and visual modes. The numeric value is the number of columns from the right edge of the screen around which vi looks for a convenient place to insert a new-line character (wm=0 is OFF). This is very convenient for touch typists. Wrapmargin behaves much like fill/nojustify mode does in nroff. Section 44.40: {writeany}, {wa} default: nowa Inhibit the checks normally made before write commands, allowing a write to any file which the system protection mechanism will allow. Section 44.41: {w300}, {w1200}, {w9600} defaults: w300=8 w1200=16 w9600=full screen minus one These are not true options but set the default size of the window for when the speed is slow (300), medium (1200), or high (9600), respectively. They are suitable for an EXINIT and make it easy to change the 8/16/full screen rule. Section 45: Limitations Here are some editor limits that the user is likely to encounter: 1024 characters per line 256 characters per global command list 128 characters per file name 128 characters in the previous inserted and deleted text in open or visual 100 characters in a shell escape command 63 characters in a string valued option 30 characters in a tag name 250000 lines in the file (this is silently enforced). The visual implementation limits the number of macros defined with map to 32, and the total number of characters in macros to be less than 512. [Editor's note: these limits may not apply to versions after 4.1BSD.]