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+*autocmd.txt*   For Vim version 7.0aa.  Last change: 2004 Apr 20
+
+
+		  VIM REFERENCE MANUAL    by Bram Moolenaar
+
+
+Automatic commands					*autocommand*
+
+For a basic explanation, see section |40.3| in the user manual.
+
+1.  Introduction		|autocmd-intro|
+2.  Defining autocommands	|autocmd-define|
+3.  Removing autocommands	|autocmd-remove|
+4.  Listing autocommands	|autocmd-list|
+5.  Events			|autocmd-events|
+6.  Patterns			|autocmd-patterns|
+7.  Groups			|autocmd-groups|
+8.  Executing autocommands	|autocmd-execute|
+9.  Using autocommands		|autocmd-use|
+
+{Vi does not have any of these commands}
+{only when the |+autocmd| feature has not been disabled at compile time}
+
+==============================================================================
+1. Introduction						*autocmd-intro*
+
+You can specify commands to be executed automatically for when reading or
+writing a file, when entering or leaving a buffer or window, and when exiting
+Vim.  For example, you can create an autocommand to set the 'cindent' option
+for files matching *.c.  You can also use autocommands to implement advanced
+features, such as editing compressed files (see |gzip-example|).  The usual
+place to put autocommands is in your .vimrc or .exrc file.
+
+							*E203* *E204* *E143*
+WARNING: Using autocommands is very powerful, and may lead to unexpected side
+effects.  Be careful not to destroy your text.
+- It's a good idea to do some testing on an expendable copy of a file first.
+  For example: If you use autocommands to decompress a file when starting to
+  edit it, make sure that the autocommands for compressing when writing work
+  correctly.
+- Be prepared for an error halfway through (e.g., disk full).  Vim will mostly
+  be able to undo the changes to the buffer, but you may have to clean up the
+  changes to other files by hand (e.g., compress a file that has been
+  decompressed).
+- If the BufRead* events allow you to edit a compressed file, the FileRead*
+  events should do the same (this makes recovery possible in some rare cases).
+  It's a good idea to use the same autocommands for the File* and Buf* events
+  when possible.
+
+==============================================================================
+2. Defining autocommands				*autocmd-define*
+
+Note: The ":autocmd" command cannot be followed by another command, since any
+'|' is considered part of the command.
+
+							*:au* *:autocmd*
+:au[tocmd] [group] {event} {pat} [nested] {cmd}
+			Add {cmd} to the list of commands that Vim will
+			execute automatically on {event} for a file matching
+			{pat}.  Vim always adds the {cmd} after existing
+			autocommands, so that the autocommands execute in the
+			order in which they were given.  See |autocmd-nested|
+			for [nested].
+
+Note that special characters (e.g., "%", "<cword>") in the ":autocmd"
+arguments are not expanded when the autocommand is defined.  These will be
+expanded when the Event is recognized, and the {cmd} is executed.  The only
+exception is that "<sfile>" is expanded when the autocmd is defined.  Example:
+>
+	:au BufNewFile,BufRead *.html so <sfile>:h/html.vim
+
+Here Vim expands <sfile> to the name of the file containing this line.
+
+When your .vimrc file is sourced twice, the autocommands will appear twice.
+To avoid this, put this command in your .vimrc file, before defining
+autocommands: >
+
+	:autocmd!	" Remove ALL autocommands for the current group.
+
+If you don't want to remove all autocommands, you can instead use a variable
+to ensure that Vim includes the autocommands only once: >
+
+	:if !exists("autocommands_loaded")
+	:  let autocommands_loaded = 1
+	:  au ...
+	:endif
+
+When the [group] argument is not given, Vim uses the current group (as defined
+with ":augroup"); otherwise, Vim uses the group defined with [group].  Note
+that [group] must have been defined before.  You cannot define a new group
+with ":au group ..."; use ":augroup" for that.
+
+While testing autocommands, you might find the 'verbose' option to be useful: >
+	:set verbose=9
+This setting makes Vim echo the autocommands as it executes them.
+
+When defining an autocommand in a script, it will be able to call functions
+local to the script and use mappings local to the script.  When the event is
+triggered and the command executed, it will run in the context of the script
+it was defined in.  This matters if |<SID>| is used in a command.
+
+When executing the commands, the messages from one command overwrites a
+previous message.  This is different from when executing the commands
+manually.  Mostly the screen will not scroll up, thus there is no hit-enter
+prompt.  When one command outputs two messages this can happen anyway.
+
+==============================================================================
+3. Removing autocommands				*autocmd-remove*
+
+:au[tocmd]! [group] {event} {pat} [nested] {cmd}
+			Remove all autocommands associated with {event} and
+			{pat}, and add the command {cmd}.  See
+			|autocmd-nested| for [nested].
+
+:au[tocmd]! [group] {event} {pat}
+			Remove all autocommands associated with {event} and
+			{pat}.
+
+:au[tocmd]! [group] * {pat}
+			Remove all autocommands associated with {pat} for all
+			events.
+
+:au[tocmd]! [group] {event}
+			Remove ALL autocommands for {event}.
+
+:au[tocmd]! [group]	Remove ALL autocommands.
+
+When the [group] argument is not given, Vim uses the current group (as defined
+with ":augroup"); otherwise, Vim uses the group defined with [group].
+
+==============================================================================
+4. Listing autocommands					*autocmd-list*
+
+:au[tocmd] [group] {event} {pat}
+			Show the autocommands associated with {event} and
+			{pat}.
+
+:au[tocmd] [group] * {pat}
+			Show the autocommands associated with {pat} for all
+			events.
+
+:au[tocmd] [group] {event}
+			Show all autocommands for {event}.
+
+:au[tocmd] [group]	Show all autocommands.
+
+If you provide the [group] argument, Vim lists only the autocommands for
+[group]; otherwise, Vim lists the autocommands for ALL groups.  Note that this
+argument behavior differs from that for defining and removing autocommands.
+
+==============================================================================
+5. Events					*autocmd-events* *E215* *E216*
+
+					*autocommand-events* *{event}*
+Vim recognizes the following events.  Vim ignores the case of event names
+(e.g., you can use "BUFread" or "bufread" instead of "BufRead").
+
+							*BufNewFile*
+BufNewFile			When starting to edit a file that doesn't
+				exist.  Can be used to read in a skeleton
+				file.
+						*BufReadPre* *E200* *E201*
+BufReadPre			When starting to edit a new buffer, before
+				reading the file into the buffer.  Not used
+				if the file doesn't exist.
+						*BufRead* *BufReadPost*
+BufRead or BufReadPost		When starting to edit a new buffer, after
+				reading the file into the buffer, before
+				executing the modelines.  See |BufWinEnter|
+				for when you need to do something after
+				processing the modelines.
+				This does NOT work for ":r file".  Not used
+				when the file doesn't exist.  Also used after
+				successfully recovering a file.
+							*BufReadCmd*
+BufReadCmd			Before starting to edit a new buffer.  Should
+				read the file into the buffer. |Cmd-event|
+							*BufFilePre*
+BufFilePre			Before changing the name of the current buffer
+				with the ":file" or ":saveas" command.
+							*BufFilePost*
+BufFilePost			After changing the name of the current buffer
+				with the ":file" or ":saveas" command.
+							*FileReadPre*
+FileReadPre			Before reading a file with a ":read" command.
+							*FileReadPost*
+FileReadPost			After reading a file with a ":read" command.
+				Note that Vim sets the '[ and '] marks to the
+				first and last line of the read.  This can be
+				used to operate on the lines just read.
+							*FileReadCmd*
+FileReadCmd			Before reading a file with a ":read" command.
+				Should do the reading of the file. |Cmd-event|
+							*FilterReadPre* *E135*
+FilterReadPre			Before reading a file from a filter command.
+				Vim checks the pattern against the name of
+				the current buffer, not the name of the
+				temporary file that is the output of the
+				filter command.
+							*FilterReadPost*
+FilterReadPost			After reading a file from a filter command.
+				Vim checks the pattern against the name of
+				the current buffer as with FilterReadPre.
+							*FileType*
+FileType			When the 'filetype' option has been set.
+				<afile> can be used for the name of the file
+				where this option was set, and <amatch> for
+				the new value of 'filetype'.
+				See |filetypes|.
+							*Syntax*
+Syntax				When the 'syntax' option has been set.
+				<afile> can be used for the name of the file
+				where this option was set, and <amatch> for
+				the new value of 'syntax'.
+				See |:syn-on|.
+							*StdinReadPre*
+StdinReadPre			Before reading from stdin into the buffer.
+				Only used when the "-" argument was used when
+				Vim was started |--|.
+							*StdinReadPost*
+StdinReadPost			After reading from the stdin into the buffer,
+				before executing the modelines.  Only used
+				when the "-" argument was used when Vim was
+				started |--|.
+						*BufWrite* *BufWritePre*
+BufWrite or BufWritePre		Before writing the whole buffer to a file.
+							*BufWritePost*
+BufWritePost			After writing the whole buffer to a file
+				(should undo the commands for BufWritePre).
+							*BufWriteCmd*
+BufWriteCmd			Before writing the whole buffer to a file.
+				Should do the writing of the file and reset
+				'modified' if successful.  The buffer contents
+				should not be changed.  |Cmd-event|
+							*FileWritePre*
+FileWritePre			Before writing to a file, when not writing the
+				whole buffer.
+							*FileWritePost*
+FileWritePost			After writing to a file, when not writing the
+				whole buffer.
+							*FileWriteCmd*
+FileWriteCmd			Before writing to a file, when not writing the
+				whole buffer.  Should do the writing to the
+				file.  Should not change the buffer.
+				|Cmd-event|
+							*FileAppendPre*
+FileAppendPre			Before appending to a file.
+							*FileAppendPost*
+FileAppendPost			After appending to a file.
+							*FileAppendCmd*
+FileAppendCmd			Before appending to a file.  Should do the
+				appending to the file. |Cmd-event|
+							*FilterWritePre*
+FilterWritePre			Before writing a file for a filter command or
+				making a diff.
+				Vim checks the pattern against the name of
+				the current buffer, not the name of the
+				temporary file that is the output of the
+				filter command.
+							*FilterWritePost*
+FilterWritePost			After writing a file for a filter command or
+				making a diff.
+				Vim checks the pattern against the name of
+				the current buffer as with FilterWritePre.
+							*FileChangedShell*
+FileChangedShell		When Vim notices that the modification time of
+				a file has changed since editing started.
+				Also when the file attributes of the file
+				change. |timestamp|
+				Mostly triggered after executing a shell
+				command, but also with a |:checktime| command
+				or when Vim regains input focus.
+				This autocommand is triggered for each changed
+				file.  It is not used when 'autoread' is set
+				and the buffer was not changed.  If a
+				FileChangedShell autocommand is present the
+				warning message and prompt is not given.
+				This is useful for reloading related buffers
+				which are affected by a single command.
+				NOTE: When this autocommand is executed, the
+				current buffer "%" may be different from the
+				buffer that was changed "<afile>".
+				NOTE: The commands must not change the current
+				buffer, jump to another buffer or delete a
+				buffer.  *E246*
+				NOTE: This event never nests, to avoid an
+				endless loop.  This means that while executing
+				commands for the FileChangedShell event no
+				other FileChangedShell event will be
+				triggered.
+							*FileChangedRO*
+FileChangedRO			Before making the first change to a read-only
+				file.  Can be used to check-out the file from
+				a source control system.  Not triggered when
+				the change was caused by an autocommand.
+				WARNING: This event is triggered when making a
+				change, just before the change is applied to
+				the text.  If the autocommand moves the cursor
+				the effect of the change is undefined.
+							*FocusGained*
+FocusGained			When Vim got input focus.  Only for the GUI
+				version and a few console versions where this
+				can be detected.
+							*FocusLost*
+FocusLost			When Vim lost input focus.  Only for the GUI
+				version and a few console versions where this
+				can be detected.
+							*FuncUndefined*
+FuncUndefined			When a user function is used but it isn't
+				defined.  Useful for defining a function only
+				when it's used.  Both <amatch> and <afile> are
+				set to the name of the function.
+							*CursorHold*
+CursorHold			When the user doesn't press a key for the time
+				specified with 'updatetime'.  Not re-triggered
+				until the user has pressed a key (i.e. doesn't
+				fire every 'updatetime' ms if you leave Vim to
+				make some coffee. :)  See |CursorHold-example|
+				for previewing tags.
+				This event is only triggered in Normal mode.
+				Note: Interactive commands cannot be used for
+				this event.  There is no hit-enter prompt,
+				the screen is updated directly (when needed).
+				Note: In the future there will probably be
+				another option to set the time.
+				Hint: to force an update of the status lines
+				use: >
+					:let &ro = &ro
+<				{only on Amiga, Unix, Win32, MSDOS and all GUI
+				versions}
+							*BufEnter*
+BufEnter			After entering a buffer.  Useful for setting
+				options for a file type.  Also executed when
+				starting to edit a buffer, after the
+				BufReadPost autocommands.
+							*BufLeave*
+BufLeave			Before leaving to another buffer.  Also when
+				leaving or closing the current window and the
+				new current window is not for the same buffer.
+				Not used for ":qa" or ":q" when exiting Vim.
+							*BufWinEnter*
+BufWinEnter			After a buffer is displayed in a window.  This
+				can be when the buffer is loaded (after
+				processing the modelines), when a hidden
+				buffer is displayed in a window (and is no
+				longer hidden) or a buffer already visible in
+				a window is also displayed in another window.
+							*BufWinLeave*
+BufWinLeave			Before a buffer is removed from a window.
+				Not when it's still visible in another window.
+				Also triggered when exiting.  It's triggered
+				before BufUnload or BufHidden.
+				NOTE: When this autocommand is executed, the
+				current buffer "%" may be different from the
+				buffer being unloaded "<afile>".
+							*BufUnload*
+BufUnload			Before unloading a buffer.  This is when the
+				text in the buffer is going to be freed.  This
+				may be after a BufWritePost and before a
+				BufDelete.  Also used for all buffers that are
+				loaded when Vim is going to exit.
+				NOTE: When this autocommand is executed, the
+				current buffer "%" may be different from the
+				buffer being unloaded "<afile>".
+							*BufHidden*
+BufHidden			Just after a buffer has become hidden.  That
+				is, when there are no longer windows that show
+				the buffer, but the buffer is not unloaded or
+				deleted.  Not used for ":qa" or ":q" when
+				exiting Vim.
+				NOTE: When this autocommand is executed, the
+				current buffer "%" may be different from the
+				buffer being unloaded "<afile>".
+							*BufNew*
+BufNew				Just after creating a new buffer.  Also used
+				just after a buffer has been renamed.  When
+				the buffer is added to the buffer list BufAdd
+				will be triggered too.
+				NOTE: When this autocommand is executed, the
+				current buffer "%" may be different from the
+				buffer being created "<afile>".
+							*BufCreate* *BufAdd*
+BufAdd or BufCreate		Just after creating a new buffer which is
+				added to the buffer list, or adding a buffer
+				to the buffer list.
+				Also used just after a buffer in the buffer
+				list has been renamed.
+				The BufCreate event is for historic reasons.
+				NOTE: When this autocommand is executed, the
+				current buffer "%" may be different from the
+				buffer being created "<afile>".
+							*BufDelete*
+BufDelete			Before deleting a buffer from the buffer list.
+				The BufUnload may be called first (if the
+				buffer was loaded).
+				Also used just before a buffer in the buffer
+				list is renamed.
+				NOTE: When this autocommand is executed, the
+				current buffer "%" may be different from the
+				buffer being deleted "<afile>".
+							*BufWipeout*
+BufWipeout			Before completely deleting a buffer.  The
+				BufUnload and BufDelete events may be called
+				first (if the buffer was loaded and was in the
+				buffer list).  Also used just before a buffer
+				is renamed (also when it's not in the buffer
+				list).
+				NOTE: When this autocommand is executed, the
+				current buffer "%" may be different from the
+				buffer being deleted "<afile>".
+							*WinEnter*
+WinEnter			After entering another window.  Not done for
+				the first window, when Vim has just started.
+				Useful for setting the window height.
+				If the window is for another buffer, Vim
+				executes the BufEnter autocommands after the
+				WinEnter autocommands.
+				Note: When using ":split fname" the WinEnter
+				event is triggered after the split but before
+				the file "fname" is loaded.
+							*WinLeave*
+WinLeave			Before leaving a window.  If the window to be
+				entered next is for a different buffer, Vim
+				executes the BufLeave autocommands before the
+				WinLeave autocommands (but not for ":new").
+				Not used for ":qa" or ":q" when exiting Vim.
+							*CmdwinEnter*
+CmdwinEnter			After entering the command-line window.
+				Useful for setting options specifically for
+				this special type of window.  This is
+				triggered _instead_ of BufEnter and WinEnter.
+				<afile> is set to a single character,
+				indicating the type of command-line.
+				|cmdwin-char|
+							*CmdwinLeave*
+CmdwinLeave			Before leaving the command-line window.
+				Useful to clean up any global setting done
+				with CmdwinEnter.  This is triggered _instead_
+				of BufLeave and WinLeave.
+				<afile> is set to a single character,
+				indicating the type of command-line.
+				|cmdwin-char|
+							*GUIEnter*
+GUIEnter			After starting the GUI successfully, and after
+				opening the window.  It is triggered before
+				VimEnter when using gvim.  Can be used to
+				position the window from a .gvimrc file: >
+	:autocmd GUIEnter * winpos 100 50
+<							*VimEnter*
+VimEnter			After doing all the startup stuff, including
+				loading .vimrc files, executing the "-c cmd"
+				arguments, creating all windows and loading
+				the buffers in them.
+							*VimLeavePre*
+VimLeavePre			Before exiting Vim, just before writing the
+				.viminfo file.  This is executed only once,
+				if there is a match with the name of what
+				happens to be the current buffer when exiting.
+				Mostly useful with a "*" pattern. >
+	:autocmd VimLeavePre * call CleanupStuff()
+<				To detect an abnormal exit use |v:dying|.
+							*VimLeave*
+VimLeave			Before exiting Vim, just after writing the
+				.viminfo file.  Executed only once, like
+				VimLeavePre.
+				To detect an abnormal exit use |v:dying|.
+							*EncodingChanged*
+EncodingChanged			Fires off when the 'encoding' option is
+				changed.  Useful to set up fonts, for example.
+							*FileEncoding*
+FileEncoding			Obsolete.  It still works and is equivalent
+				to |EncodingChanged|.
+							*RemoteReply*
+RemoteReply			When a reply from a Vim that functions as
+				server was received |server2client()|.
+				<amatch> is equal to the {serverid} from which
+				the reply was sent, and <afile> is the actual
+				reply string.
+				Note that even if an autocommand is defined,
+				the reply should be read with |remote_read()|
+				to consume it.
+							*TermChanged*
+TermChanged			After the value of 'term' has changed.  Useful
+				for re-loading the syntax file to update the
+				colors, fonts and other terminal-dependent
+				settings.  Executed for all loaded buffers.
+							*TermResponse*
+TermResponse			After the response to |t_RV| is received from
+				the terminal.  The value of |v:termresponse|
+				can be used to do things depending on the
+				terminal version.
+							*UserGettingBored*
+UserGettingBored		When the user hits CTRL-C.  Just kidding! :-)
+							*User*
+User				Never executed automatically.  To be used for
+				autocommands that are only executed with
+				":doautocmd".
+
+You can specify a comma-separated list of event names.  No white space can be
+used in this list.  The command applies to all the events in the list.
+
+For READING FILES there are four kinds of events possible:
+	BufNewFile			starting to edit a non-existent file
+	BufReadPre	BufReadPost	starting to edit an existing file
+	FilterReadPre	FilterReadPost	read the temp file with filter output
+	FileReadPre	FileReadPost	any other file read
+Vim uses only one of these four kinds when reading a file.  The "Pre" and
+"Post" events are both triggered, before and after reading the file.
+
+Note that the autocommands for the *ReadPre events and all the Filter events
+are not allowed to change the current buffer (you will get an error message if
+this happens).  This is to prevent the file to be read into the wrong buffer.
+
+Note that the 'modified' flag is reset AFTER executing the BufReadPost
+and BufNewFile autocommands.  But when the 'modified' option was set by the
+autocommands, this doesn't happen.
+
+You can use the 'eventignore' option to ignore a number of events or all
+events.
+
+==============================================================================
+6. Patterns					*autocmd-patterns* *{pat}*
+
+The file pattern {pat} is tested for a match against the file name in one of
+two ways:
+1. When there is no '/' in the pattern, Vim checks for a match against only
+   the tail part of the file name (without its leading directory path).
+2. When there is a '/' in the pattern,  Vim checks for a match against the
+   both short file name (as you typed it) and the full file name (after
+   expanding it to a full path and resolving symbolic links).
+
+Examples: >
+	:autocmd BufRead *.txt		set et
+Set the 'et' option for all text files. >
+
+	:autocmd BufRead /vim/src/*.c	set cindent
+Set the 'cindent' option for C files in the /vim/src directory. >
+
+	:autocmd BufRead /tmp/*.c	set ts=5
+If you have a link from "/tmp/test.c" to "/home/nobody/vim/src/test.c", and
+you start editing "/tmp/test.c", this autocommand will match.
+
+Note:  To match part of a path, but not from the root directory, use a '*' as
+the first character.  Example: >
+	:autocmd BufRead */doc/*.txt	set tw=78
+This autocommand will for example be executed for "/tmp/doc/xx.txt" and
+"/usr/home/piet/doc/yy.txt".  The number of directories does not matter here.
+
+
+The file name that the pattern is matched against is after expanding
+wildcards.  Thus is you issue this command: >
+	:e $ROOTDIR/main.$EXT
+The argument is first expanded to: >
+	/usr/root/main.py
+Before it's matched with the pattern of the autocommand.  Careful with this
+when using events like FileReadCmd, the value of <amatch> may not be what you
+expect.
+
+
+Environment variables can be used in a pattern: >
+	:autocmd BufRead $VIMRUNTIME/doc/*.txt  set expandtab
+And ~ can be used for the home directory (if $HOME is defined): >
+	:autocmd BufWritePost ~/.vimrc   so ~/.vimrc
+	:autocmd BufRead ~archive/*      set readonly
+The environment variable is expanded when the autocommand is defined, not when
+the autocommand is executed.  This is different from the command!
+
+							*file-pattern*
+The pattern is interpreted like mostly used in file names:
+	*	matches any sequence of characters
+	?	matches any single character
+	\?	matches a '?'
+	.	matches a '.'
+	~	matches a '~'
+	,	separates patterns
+	\,	matches a ','
+	{ }	like \( \) in a |pattern|
+	,	inside { }: like \| in a |pattern|
+	\	special meaning like in a |pattern|
+	[ch]	matches 'c' or 'h'
+	[^ch]   match any character but 'c' and 'h'
+
+Note that for all systems the '/' character is used for path separator (even
+MS-DOS and OS/2).  This was done because the backslash is difficult to use
+in a pattern and to make the autocommands portable across different systems.
+
+
+Matching with the pattern is done when an event is triggered.  Changing the
+buffer name in one of the autocommands, or even deleting the buffer, does not
+change which autocommands will be executed.  Example: >
+
+	au BufEnter *.foo  bdel
+	au BufEnter *.foo  set modified
+
+This will delete the current buffer and then set 'modified' in what has become
+the current buffer instead.  Vim doesn't take into account that "*.foo"
+doesn't match with that buffer name.  It matches "*.foo" with the name of the
+buffer at the moment the event was triggered.
+
+==============================================================================
+7. Groups						*autocmd-groups*
+
+Autocommands can be put together in a group.  This is useful for removing or
+executing a group of autocommands.  For example, all the autocommands for
+syntax highlighting are put in the "highlight" group, to be able to execute
+":doautoall highlight BufRead" when the GUI starts.
+
+When no specific group is selected, Vim uses the default group.  The default
+group does not have a name.  You cannot execute the autocommands from the
+default group separately; you can execute them only by executing autocommands
+for all groups.
+
+Normally, when executing autocommands automatically, Vim uses the autocommands
+for all groups.  The group only matters when executing autocommands with
+":doautocmd" or ":doautoall", or when defining or deleting autocommands.
+
+The group name can contain any characters except white space.  The group name
+"end" is reserved (also in uppercase).
+
+The group name is case sensitive.  Note that this is different from the event
+name!
+
+							*:aug* *:augroup*
+:aug[roup] {name}		Define the autocmd group name for the
+				following ":autocmd" commands.  The name "end"
+				or "END" selects the default group.
+
+						*:augroup-delete* *E367*
+:aug[roup]! {name}		Delete the autocmd group {name}.  Don't use
+				this if there is still an autocommand using
+				this group!  This is not checked.
+
+To enter autocommands for a specific group, use this method:
+1. Select the group with ":augroup {name}".
+2. Delete any old autocommands with ":au!".
+3. Define the autocommands.
+4. Go back to the default group with "augroup END".
+
+Example: >
+	:augroup uncompress
+	:  au!
+	:  au BufEnter *.gz	%!gunzip
+	:augroup END
+
+This prevents having the autocommands defined twice (e.g., after sourcing the
+.vimrc file again).
+
+==============================================================================
+8. Executing autocommands				*autocmd-execute*
+
+Vim can also execute Autocommands non-automatically.  This is useful if you
+have changed autocommands, or when Vim has executed the wrong autocommands
+(e.g., the file pattern match was wrong).
+
+Note that the 'eventignore' option applies here too.  Events listed in this
+option will not cause any commands to be executed.
+
+					*:do* *:doau* *:doautocmd* *E217*
+:do[autocmd] [group] {event} [fname]
+			Apply the autocommands matching [fname] (default:
+			current file name) for {event} to the current buffer.
+			You can use this when the current file name does not
+			match the right pattern, after changing settings, or
+			to execute autocommands for a certain event.
+			It's possible to use this inside an autocommand too,
+			so you can base the autocommands for one extension on
+			another extension.  Example: >
+				:au Bufenter *.cpp so ~/.vimrc_cpp
+				:au Bufenter *.cpp doau BufEnter x.c
+<			Be careful to avoid endless loops.  See
+			|autocmd-nested|.
+
+			When the [group] argument is not given, Vim executes
+			the autocommands for all groups.  When the [group]
+			argument is included, Vim executes only the matching
+			autocommands for that group.  Note: if you use an
+			undefined group name, Vim gives you an error message.
+
+						*:doautoa* *:doautoall*
+:doautoa[ll] [group] {event} [fname]
+			Like ":doautocmd", but apply the autocommands to each
+			loaded buffer.  Note that {fname} is used to select
+			the autocommands, not the buffers to which they are
+			applied.
+			Careful: Don't use this for autocommands that delete a
+			buffer, change to another buffer or change the
+			contents of a buffer; the result is unpredictable.
+			This command is intended for autocommands that set
+			options, change highlighting, and things like that.
+
+==============================================================================
+9. Using autocommands					*autocmd-use*
+
+For WRITING FILES there are four possible sets of events.  Vim uses only one
+of these sets for a write command:
+
+BufWriteCmd	BufWritePre	BufWritePost	writing the whole buffer
+		FilterWritePre	FilterWritePost	writing to filter temp file
+FileAppendCmd	FileAppendPre	FileAppendPost	appending to a file
+FileWriteCmd	FileWritePre	FileWritePost	any other file write
+
+When there is a matching "*Cmd" autocommand, it is assumed it will do the
+writing.  No further writing is done and the other events are not triggered.
+|Cmd-event|
+
+Note that the *WritePost commands should undo any changes to the buffer that
+were caused by the *WritePre commands; otherwise, writing the file will have
+the side effect of changing the buffer.
+
+Before executing the autocommands, the buffer from which the lines are to be
+written temporarily becomes the current buffer.  Unless the autocommands
+change the current buffer or delete the previously current buffer, the
+previously current buffer is made the current buffer again.
+
+The *WritePre and *AppendPre autocommands must not delete the buffer from
+which the lines are to be written.
+
+The '[ and '] marks have a special position:
+- Before the *ReadPre event the '[ mark is set to the line just above where
+  the new lines will be inserted.
+- Before the *ReadPost event the '[ mark is set to the first line that was
+  just read, the '] mark to the last line.
+- Before executing the *WritePre and *AppendPre autocommands the '[ mark is
+  set to the first line that will be written, the '] mark to the last line.
+Careful: '[ and '] change when using commands that change the buffer.
+
+In commands which expect a file name, you can use "<afile>" for the file name
+that is being read |:<afile>| (you can also use "%" for the current file
+name).  "<abuf>" can be used for the buffer number of the currently effective
+buffer.  This also works for buffers that doesn't have a name.  But it doesn't
+work for files without a buffer (e.g., with ":r file").
+
+							*gzip-example*
+Examples for reading and writing compressed files: >
+  :augroup gzip
+  :  autocmd!
+  :  autocmd BufReadPre,FileReadPre	*.gz set bin
+  :  autocmd BufReadPost,FileReadPost	*.gz '[,']!gunzip
+  :  autocmd BufReadPost,FileReadPost	*.gz set nobin
+  :  autocmd BufReadPost,FileReadPost	*.gz execute ":doautocmd BufReadPost " . expand("%:r")
+  :  autocmd BufWritePost,FileWritePost	*.gz !mv <afile> <afile>:r
+  :  autocmd BufWritePost,FileWritePost	*.gz !gzip <afile>:r
+
+  :  autocmd FileAppendPre		*.gz !gunzip <afile>
+  :  autocmd FileAppendPre		*.gz !mv <afile>:r <afile>
+  :  autocmd FileAppendPost		*.gz !mv <afile> <afile>:r
+  :  autocmd FileAppendPost		*.gz !gzip <afile>:r
+  :augroup END
+
+The "gzip" group is used to be able to delete any existing autocommands with
+":autocmd!", for when the file is sourced twice.
+
+("<afile>:r" is the file name without the extension, see |:_%:|)
+
+The commands executed for the BufNewFile, BufRead/BufReadPost, BufWritePost,
+FileAppendPost and VimLeave events do not set or reset the changed flag of the
+buffer.  When you decompress the buffer with the BufReadPost autocommands, you
+can still exit with ":q".  When you use ":undo" in BufWritePost to undo the
+changes made by BufWritePre commands, you can still do ":q" (this also makes
+"ZZ" work).  If you do want the buffer to be marked as modified, set the
+'modified' option.
+
+To execute Normal mode commands from an autocommand, use the ":normal"
+command.  Use with care!  If the Normal mode command is not finished, the user
+needs to type characters (e.g., after ":normal m" you need to type a mark
+name).
+
+If you want the buffer to be unmodified after changing it, reset the
+'modified' option.  This makes it possible to exit the buffer with ":q"
+instead of ":q!".
+
+							*autocmd-nested* *E218*
+By default, autocommands do not nest.  If you use ":e" or ":w" in an
+autocommand, Vim does not execute the BufRead and BufWrite autocommands for
+those commands.  If you do want this, use the "nested" flag for those commands
+in which you want nesting.  For example: >
+  :autocmd FileChangedShell *.c nested e!
+The nesting is limited to 10 levels to get out of recursive loops.
+
+It's possible to use the ":au" command in an autocommand.  This can be a
+self-modifying command!  This can be useful for an autocommand that should
+execute only once.
+
+There is currently no way to disable the autocommands.  If you want to write a
+file without executing the autocommands for that type of file, write it under
+another name and rename it with a shell command.  In some situations you can
+use the 'eventignore' option.
+
+Note: When reading a file (with ":read file" or with a filter command) and the
+last line in the file does not have an <EOL>, Vim remembers this.  At the next
+write (with ":write file" or with a filter command), if the same line is
+written again as the last line in a file AND 'binary' is set, Vim does not
+supply an <EOL>.  This makes a filter command on the just read lines write the
+same file as was read, and makes a write command on just filtered lines write
+the same file as was read from the filter.  For example, another way to write
+a compressed file: >
+
+  :autocmd FileWritePre *.gz   set bin|'[,']!gzip
+  :autocmd FileWritePost *.gz  undo|set nobin
+<
+							*autocommand-pattern*
+You can specify multiple patterns, separated by commas.  Here are some
+examples: >
+
+  :autocmd BufRead   *		set tw=79 nocin ic infercase fo=2croq
+  :autocmd BufRead   .letter	set tw=72 fo=2tcrq
+  :autocmd BufEnter  .letter	set dict=/usr/lib/dict/words
+  :autocmd BufLeave  .letter	set dict=
+  :autocmd BufRead,BufNewFile   *.c,*.h	set tw=0 cin noic
+  :autocmd BufEnter  *.c,*.h	abbr FOR for (i = 0; i < 3; ++i)<CR>{<CR>}<Esc>O
+  :autocmd BufLeave  *.c,*.h	unabbr FOR
+
+For makefiles (makefile, Makefile, imakefile, makefile.unix, etc.): >
+
+  :autocmd BufEnter  ?akefile*	set include=^s\=include
+  :autocmd BufLeave  ?akefile*	set include&
+
+To always start editing C files at the first function: >
+
+  :autocmd BufRead   *.c,*.h	1;/^{
+
+Without the "1;" above, the search would start from wherever the file was
+entered, rather than from the start of the file.
+
+						*skeleton* *template*
+To read a skeleton (template) file when opening a new file: >
+
+  :autocmd BufNewFile  *.c	0r ~/vim/skeleton.c
+  :autocmd BufNewFile  *.h	0r ~/vim/skeleton.h
+  :autocmd BufNewFile  *.java	0r ~/vim/skeleton.java
+
+To insert the current date and time in a *.html file when writing it: >
+
+  :autocmd BufWritePre,FileWritePre *.html   ks|call LastMod()|'s
+  :fun LastMod()
+  :  if line("$") > 20
+  :    let l = 20
+  :  else
+  :    let l = line("$")
+  :  endif
+  :  exe "1," . l . "g/Last modified: /s/Last modified: .*/Last modified: " .
+  :  \ strftime("%Y %b %d")
+  :endfun
+
+You need to have a line "Last modified: <date time>" in the first 20 lines
+of the file for this to work.  Vim replaces <date time> (and anything in the
+same line after it) with the current date and time.  Explanation:
+	ks		mark current position with mark 's'
+	call LastMod()  call the LastMod() function to do the work
+	's		return the cursor to the old position
+The LastMod() function checks if the file is shorter than 20 lines, and then
+uses the ":g" command to find lines that contain "Last modified: ".  For those
+lines the ":s" command is executed to replace the existing date with the
+current one.  The ":execute" command is used to be able to use an expression
+for the ":g" and ":s" commands.  The date is obtained with the strftime()
+function.  You can change its argument to get another date string.
+
+When entering :autocmd on the command-line, completion of events and command
+names may be done (with <Tab>, CTRL-D, etc.) where appropriate.
+
+Vim executes all matching autocommands in the order that you specify them.
+It is recommended that your first autocommand be used for all files by using
+"*" as the file pattern.  This means that you can define defaults you like
+here for any settings, and if there is another matching autocommand it will
+override these.  But if there is no other matching autocommand, then at least
+your default settings are recovered (if entering this file from another for
+which autocommands did match).  Note that "*" will also match files starting
+with ".", unlike Unix shells.
+
+						    *autocmd-searchpat*
+Autocommands do not change the current search patterns.  Vim saves the current
+search patterns before executing autocommands then restores them after the
+autocommands finish.  This means that autocommands do not affect the strings
+highlighted with the 'hlsearch' option.  Within autocommands, you can still
+use search patterns normally, e.g., with the "n" command.
+If you want an autocommand to set the search pattern, such that it is used
+after the autocommand finishes, use the ":let @/ =" command.
+The search-highlighting cannot be switched off with ":nohlsearch" in an
+autocommand.  Use the 'h' flag in the 'viminfo' option to disable search-
+highlighting when starting Vim.
+
+							*Cmd-event*
+When using one of the "*Cmd" events, the matching autocommands are expected to
+do the file reading or writing.  This can be used when working with a special
+kind of file, for example on a remote system.
+CAREFUL: If you use these events in a wrong way, it may have the effect of
+making it impossible to read or write the matching files!  Make sure you test
+your autocommands properly.  Best is to use a pattern that will never match a
+normal file name, for example "ftp://*".
+
+When defining a BufReadCmd it will be difficult for Vim to recover a crashed
+editing session.  When recovering from the original file, Vim reads only those
+parts of a file that are not found in the swap file.  Since that is not
+possible with a BufReadCmd, use the |:preserve| command to make sure the
+original file isn't needed for recovery.  You might want to do this only when
+you expect the file to be modified.
+
+The |v:cmdarg| variable holds the "++enc=" and "++ff=" argument that are
+effective.  These should be used for the command that reads/writes the file.
+The |v:cmdbang| variable is one when "!" was used, zero otherwise.
+
+See the $VIMRUNTIME/plugin/netrw.vim for examples.
+
+ vim:tw=78:ts=8:ft=help:norl: