Vim is mostly POSIX 1003.2-1 compliant. The commands known to be missing are "Q", ":append", ":change", ":insert", ":open" and ":z". There are probably a lot of small differences.

THE MOST INTERESTING ADDITIONS

Vi compatibility.

Support for different systems.

• All Unix systems (it works on all systems it was tested on).
• Amiga (500, 1000, 1200, 2000, 3000, 4000, ...).
• MS-DOS in real-mode (no additional drivers required).
• In protected mode on Windows 3.1 and MS-DOS (DPMI driver required).
• Windows 95 and Windows NT, with support for long file names.
• OS/2 (in an MS-DOS console window).
• Macintosh (although it has not been tested much).

Multi level undo.

When all changes in a buffer have been undone, the buffer is not considered changed anymore. You can exit it with :q, without <!>.

Multiple windows and buffers.

Repeat a series of commands.

Flexible insert mode.

CTRL-O can be used to execute a single command-mode command. This is almost the same as hitting <Esc>, typing the command and hitting 'a'.

Visual mode.

Block operators.

Online help system.

Command line editing and history.

The command lines are remembered. The up/down cursor keys can be used to recall previous command lines. The 'history' option can be set to the number of lines that will be remembered.

Command line completion.

If there are multiple matches, CTRL-N (next) and CTRL-P (previous) will walk through the matches. <Tab> works like CTRL-N, but wraps around to the first match.

The 'wildchar' option can be set to the character for command line completion, <Tab> is the default. CTRL-D can be typed after an (incomplete) wildcard; all matches will be listed. CTRL-A will insert all matches. CTRL-L will insert the longest common part of the matches.

Horizontal scrolling.

Text formatting.

Edit-compile-edit speedup.

Each line in the error file is scanned for the name of a file, line number and error message. The 'errorformat' option can be set to a list of scanf-like strings to handle output from many compilers.

The ":cn" command can be used to jump to the next error. ":cl" lists all the error messages. Other commands are available (almost the same as with Manx's Z editor on the Amiga). The 'errorfile' option has the name of the file with error messages. The 'makeprg' option contains the name of the program to be executed with the ":make" command. The 'shellpipe' option contains the string to be used to put the output of the compiler into the errorfile.

Improved indenting for C programs

Comments can be automatically formatted. The 'comments' and 'nestedcomments' options can be set to the characters that start and end a comment. This works best for C code, but also works for e-mail (">" at start of the line) and other types of text. The "=" operator can be used to re-indent lines.

Searching for words in include files

Word completion in Insert mode

Automatic commands

Viminfo

Mouse support

Graphical User Interface (GUI)

IMPROVEMENTS FROM VERSION 3.0 TO VERSION 4.0

Besides the big changes mentioned here there are an awful lot of small improvements. For a more complete list see new_features.

New on-line help system new_help Help is now displayed in a window. Tags can be used to jump around in all the documentation (like hypertext links).

Command line editing improved new_commandline Separate history for search commands. Improved command line completion.

Improved indenting for C programs

Searching for words in include files

Word completion in Insert mode

Automatic commands

Text objects

Options

Support for editing one-line paragraphs

Usage of key names

Viminfo

Compilation improvements

Tag support improved

Improved (error) messages

Swap file

Mouse support

Graphical User Interface (GUI)

Support for Windows 95/NT

Miscellaneous new features

vi compatibility improvements

OLDER VIM FEATURES

These features were already present in Vim version 3.0.

• Command line options:
  • When Vim is started with "-v" (View) then readonly mode is used (includes "-n").
  • When Vim is started with "-b" (Binary) then some options are set to be able to edit binary or executable files.
  • When Vim is started with "-s scriptfile", the characters read from "scriptfile" are treated as if you typed them. If end of file is reached before the editor exits, further characters are read from the console.
  • The "-w" option can be used to record all typed characters in a script file. This file can then be used to redo the editing, possibly on another file or after changing some commands in the script file.
  • The "-n" option disables the writing of a ".swp" file (see below).
  • The "-c command" option does the same as the "+command" option.
  • The "-T terminal" option sets the terminal type.
  • The "-e" option starts Vim in quickfix mode.
  • The "-o" option opens a window for each argument. "-o4" opens four windows.
• In command mode:
  • Missing command: 'Q' (go to Ex mode).
  • Missing Ex commands: append, change, insert, open and z.
  • The command characters are shown in the last line of the screen. They are removed when the command is finished. If you do not want this (on a slow terminal) reset the 'showcmd' option.
  • If the 'ruler' option is set, the current cursor position is shown in the last line of the screen.
  • 'u' and CTRL-R accept a count for the number of undos/redos.
  • 'U' still works after having moved off the last changed line and after 'u'. Nulls in the file are replaced with <NL> internally. This allows editing of binary files (more or less).
  • Characters with the 8th bit set are displayed. The characters between '~' and 0xa0 are displayed as "~?", "~@", "~A", etc., unless the "graphic' option is set.
  • '=' is an operator to filter lines through an external command (vi: lisp stuff). The name of the command can be set with the 'equalprg' option. The default is "indent".
  • '][' goes to the next ending of a C function ('}' in column 1).
  • '[]' goes to the previous ending of a C function ('}' in column 1).
  • ']f', '[f' and 'gf' start editing the file whose name is under the cursor.
  • CTRL-W f splits the window and starts editing the file whose name is under the cursor.
  • '*' searches forward for the identifier under the cursor, '#' backward.
  • 'K' runs the program defined by the "keywordprg" option, with the identifier under the cursor as argument.
  • '%' can be preceded with a count. The cursor jumps to the line that percentage down in the file. The normal '%' function to jump to the matching brace skips braces inside quotes.
  • With the CTRL-] command, the cursor may be in the middle of the identifier.
  • The used tags are remembered. Commands that can be used with the tag stack are CTRL-T, ':pop' and ':tag'. ':tags' lists the tag stack.
  • The 'tags' option can be set to a list of tag file names. Thus multiple tag files can be used. For file names that start with '.', the '.' is replaced with the path of the current file. This makes it possible to use a tags file in the same directory as the file being edited.
  • Previously used file names are remembered in the alternate file name list.
  • CTRL-^ accepts a count, which is an index in this list.
  • Search patterns have more features. The <NL> character is seen as part of the search pattern and the substitute string of ":s". Vi sees it as the end of the command.
  • Searches can put the cursor on the end of a match and may include a character offset.
  • Count added to '~', ':next', ':Next', 'n' and 'N'.
  • The command ":next!" with 'autowrite' set does not write the file. In vi the file was written, but this is considered to be a bug, because one does not expect it and the file is not written with ':rewind!'.
  • "5r<CR>" replaces five characters with five line breaks. Vi replaces five characters with a single line break.
  • In Vi when entering a <CR> in replace mode deletes a character only when 'ai' is set (but does not show it until you hit <Esc>). Vim always deletes a character (and shows it immediately).
  • Added :wnext command. Same as ":write" followed by ":next".
  • The ":w!" command always writes, also when the file is write protected.
  • If option "tildeop" has been set, '~' is an operator (must be followed by a movement command).
  • With the 'J' (join) command you can reset the 'joinspaces' (js) option to have only one space after a period (Vi inserts two spaces).
  • 'cw' can be used to change white space formed by several characters (Vi is confusing: 'cw' only changes one space, while 'dw' deletes all white space).
  • 'o' and 'O' accept a count for repeating the insert (Vi clears a part of display).
  • ':dis' command shows the contents of the yank registers.
  • Previously used file names are remembered in the alternate file name list. ":files" command shows the list of alternate filenames. '#'<N> is replaced with the <N>th alternate filename in the list. "#<" is replaced with the current filename without extension.
  • Flags after command not supported (no plans to include it).
  • On non-UNIX systems ":cd" command shows current directory instead of going to the home directory. ":pwd" prints the current directory on all systems.
  • ':source!' command reads Vi commands from a file.
  • ':mkexrc' command writes current modified options and mappings to a ".exrc" file. ':mkvimrc' writes to a ".vimrc" file.
  • No check for "tail recursion" with mappings. This allows things like ":map! foo ^]foo".
  • When a mapping starts with number, vi loses the count typed before it (e.g. when using the mapping ":map g 4G" the command "7g" goes to line 4). This is considered a vi bug. Vim concatenates the counts (in the example it becomes "74G"), as most people would expect.
  • The :put! command inserts the contents of a register above the current line.
  • The 'p' and 'P' commands of vi cannot be repeated with '.' when the putted text is less than a line. In Vim they can always be repeated.
  • The named register '.' can be used with commands p, P and :put. The contents of the register is the last inserted text.
  • ":noremap" command can be used to enter a mapping that will not be remapped. This is useful to exchange the meaning of two keys. ":cmap", ":cunmap" and ":cnoremap" can be used for mapping in command line editing only. ":imap", ":iunmap" and ":inoremap" can be used for mapping in insert mode only. Similar commands exist for abbreviations: ":noreabbrev", ":iabbrev" ":cabbrev", ":iunabbrev", ":cunabbrev", ":inoreabbrev", ":cnoreabbrev".
  • In vi the command ":map foo bar" would remove a previous mapping ":map bug foo". This is considered a bug, so it is not included in Vim. ":unmap! foo" does remove ":map! bug foo", because unmapping would be very difficult otherwise (this is vi compatible).
  • ":@r" command executes register r (is in some versions of vi).
  • The ':' register contains the last command line.
  • The '%' register contians the current file name.
  • CTRL-O/CTRL-I can be used to jump to older/newer positions. These are the same positions as used with the '' command, but may be in another file. The ':jumps' command lists the older positions.
  • If the 'shiftround' option is set, an indent is rounded to a multiple of 'shiftwidth' with '>' and '<' commands.
  • The 'scrolljump' option can be set to the minimum number of lines to scroll when the cursor gets off the screen. Use this when scrolling is slow.
  • The 'scrolloff' option can be set to the minimum number of lines to keep above and below the cursor. This gives some context to where you are editing. When set to a large number the cursor line is always in the middle of the window.
  • Uppercase marks can be used to jump between files. The ':marks' command lists all currently set marks. The commands "']" and "`]" jump to the end of the previous operator or end of the text inserted with the put command. "'[" and "`[" do jump to the start.
  • The 'shelltype' option can be set to reflect the type of shell used.
  • The 'highlight' option can be set for the higlight mode to be used for several commands.
  • The CTRL-A (add) and CTRL-X (subtract) commands are new. The count to the command (default 1) is added to/subtracted from the number at or after the cursor. That number may be decimal, octal (starts with a '0') or hexadecimal (starts with '0x'). Very useful in macros.
  • With the :set command the prefix "inv" can be used to invert toggle options.
  • In both Vi and Vim you can create a line break with the ":substitute" command by using a CTRL-M. For Vi this means you cannot insert a real CTRL-M in the text. With Vim you can put a real CTRL-M in the text by preceding it with a CTRL-V.
• In insert mode:
  • If the 'revins' option is set, insert happens backwards. This is for typing Hebrew. When inserting normal characters the cursor will not be shifted and the text moves rightwards. Backspace, CTRL-W and CTRL-U will also work in the opposite direction. CTRL-B toggles the 'revins' option. In replace mode 'revins' has no effect.
  • The backspace key can be used just like CTRL-D to remove auto-indents.
  • You can backspace, ctrl-U and CTRL-W over line breaks if the 'backspace' (bs) option is set to non-zero. You can backspace over the start of insert if the 'backspace' option is set to 2.
  • When the 'paste' option is set, a few option are reset and mapping in insert mode and abbreviation are disabled. This allows for pasting text in windowing systems without unexpected results. When the 'paste' option is reset, the old option values are restored.
  • CTRL-T/CTRL-D always insert/delete an indent in the current line, no matter what column the cursor is in.
  • CTRL-@ (insert previously inserted text) works always (Vi: only when typed as first character).
  • CTRL-A works like CTRL-@ but does not leave insert mode.
  • CTRL-R <0-9a-z> can be used to insert the contents of a register.
  • When the 'smartindent' (si) option is set, C programs will be better auto-indented.
  • CTRL-Y and CTRL-E can be used to copy a character from above/below the current cursor position.
  • After CTRL-V you can enter a three digit decimal number. This byte value is inserted in the text as a single character. Useful for international characters that are not on your keyboard.
  • When the 'expandtab' (et) option is set, a <Tab> is expanded to the appropriate number of spaces.
  • The window always reflects the contents of the buffer (Vi does not do this when changing text and in some other cases).
  • If Vim is compiled with DIGRAPHS defined, digraphs are supported. A set of normal Amiga digraphs is included. They are shown with the :digraph" command. More can be added with ":digraph {char1}{char2} {number}". A digraph is entered with "CTRL-K {char1} {char2}" or "{char1} BS {char2}" (only when 'digraph' option is set).
  • When repeating an insert, e.g. "10atest <Esc>" vi would only handle wrapmargin for the first insert. Vim does it for all.
  • A count to the 'i' or 'a' command is used for all the text. Vi uses the count only for one line. "3iabc<NL>def<Esc>" would insert "abcabcacc<NL>def" in Vi but "abc<NL>defabc<NL>defabc<NL>def" in Vim.
• In command line mode:
  • <Esc> terminates the command line without executing it. In vi the command line would be executed, which is not what most people expect (hitting <Esc> should always get you back to command mode). To avoid problems with some obscure macros, an <Esc> in a macro will execute the command. If you want a typed <Esc> to execute the command like vi does you can fix this with
    ":cmap ^V<Esc> ^V<CR>"
• general:
  • Missing options: autoprint (ap), beautify (bf), hardtabs (ht), lisp, mesg, open, optimize (op), prompt, redraw, slowopen (slow), window, w300, w1200 and w9600. These options can be set but are otherwise ignored.
  • When the 'compatible' option is set, all options are set for maximum vi-compatibility
  • The 'ttimeout' option is like 'timeout', but only works for cursor and function keys, not for ordinary mapped characters. The 'timoutlen' option gives the number of milliseconds that is waited for. If the 'esckeys' option is not set, cursor and function keys that start with <Esc> are not recognized in insert mode.
  • There is an option for each terminal string. Can be used when termcap is not supported or to change individual strings.
  • When the 'textmode' option is set (default for MSDOS) <CR><NL> is used as line separator. When reset (default for Unix and Amiga) <NL> is used. When the 'textauto' option is set, Vim tries to detect the type of line separator used by reading up to the first <NL>. The 'textmode' option is set accordingly.
  • On systems that have no job control (older Unix systems and non-Unix systems) the CTRL-Z, ":stop" or ":suspend" command starts a new shell.
  • If Vim is started on the Amiga without an interactive window for output, a window is opened (and :sh still works). You can give a device to use for editing with the '-d' argument, e.g. "-d con:20/20/600/150".
  • On startup the VIMINIT or EXINIT environment variables, the file s:.vimrc or s:.exrc and .vimrc or .exrc are read for initialization commands. When reading .vimrc and .exrc some commands are not allowed because of security reasons (shell commands and writing to a file, :map commands are echoed). This can be overrided with the 'secure' option.
  • Line length can be at least up to the maximum value of an int (for the Amiga 32767 characters, for most 32-bit systems much larger). Editing such lines is not always possible. File length up to 2147483646 lines. If a line is larger than the screen, the last line is filled with <@>s and only the part of the line before that is shown (unless 'wrap' option is reset).
  • The 'columns' option is used to set or get the width of the display.
  • The name of the current file name is shown in the title bar of the window.
  • Wildcards in file names are expanded.
  • Option settings are read from the first and last few lines of the file. Option 'modelines' determines how many lines are tried (default is 5). Note that this is different from the Vi versions that can execute any Ex command in a modeline (a major security problem).
  • If the 'insertmode' option is set (e.g. in .exrc), Vim starts in insert mode.
  • All text is kept in memory. Available memory limits the file size (and other things such as undo). This may be a problem with MSDOS, is hardly a problem ont the Amiga and almost never with Unix.
  • If the 'backup' or 'writebackup' option is set: Before a file is overwritten, a backup file (.bak) is made. If the "backup" option is set it is left behind.
  • If the 'binary' option is set and the file does not have an end-of-line for the last line, the end-of-line is not appended when writing.
  • Vim creates a file ending in ".swp" to store parts of the file that have been changed or that do not fit in memory. This file can be used to recover from an aborted editing session with "vim -r file". Using the swap file can be switched off by setting the 'updatecount' option to 0 or starting Vim with the "-n" option. Use the 'directory' option for placing the .swp file somewhere else.
  • The 'shortname' (sn) option, when set, tells Vim that ".bak" and ".swp" filenames are to be MSDOS-like: 8 characters plus 3 for extention. This should be used on messydos or crossdos filesystems on the Amiga. If this option is off, Vim tries to guess if MSDOS filename restrictions are effective.
  • Error messages are shown at least one second (Vi overwrites error messages).
  • If Vim asks to "Hit RETURN to continue", you can hit any key. Characters other than <CR>, <NL> and <Space> are interpreted as the (start of) a command. (Vi only accepts a command starting with ':').
  • The contents of the numbered and unnamed registers is remembered when changing files.
  • The "No lines in buffer" message is a normal message instead of an error message, since that may cause a mapping to be aborted.
  • The AUX: device of the Amiga is supported.