LargeFile.txt	Editing Large Files Quickly			Jan 08, 2015

Author:  Charles E. Campbell  <NdrOchip@ScampbellPfamily.AbizM>
	  (remove NOSPAM from Campbell's email first)
Copyright: (c) 2004-2015 by Charles E. Campbell	LargeFile-copyright
           The VIM LICENSE applies to LargeFile.vim
           (see copyright) except use "LargeFile" instead of "Vim"
	   No warranty, express or implied.  Use At-Your-Own-Risk.

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1. Large File Plugin			:Unlarge :Large largefile {{{1

The LargeFile plugin is fairly short -- it simply sets up an :autocmd that
checks for large files.  There is one parameter:
	g:LargeFile
which, by default, is 20 (ie. 20MB).  Thus with this value of g:LargeFile,
20MByte files and larger are considered to be "large files"; smaller ones
aren't.  Of course, you as a user may set g:LargeFile to whatever you want in
your <.vimrc> (in units of MBytes).

LargeFile.vim always assumes that when the file size is larger than what
can fit into a signed integer (2^31, ie. about 2GB) that the file is "Large".

Essentially, this autocmd simply turns off a number of features in Vim,
including event handling, undo, and syntax highlighting, in the interest of
speed and responsiveness.

LargeFile.vim borrows from vimtip#611.

To undo what LargeFile does, type
	:Unlarge
To redo what LargeFile does, type
	:Large
To forcibly have the file handled as a "large file", type
	:Large!

Note that LargeFile cannot alleviate hardware limitations; vim on 32-bit
machines is limited to editing 2G files.  If your vim is compiled on a 64-bit
machine such that it can take advantage of the additional address space, then
presumably vim could edit up to 9.7 quadrillion byte files (not that I've ever
tried that!).

You may be interested in the following reply Tim Chase made to a question
about loading a large file:

	  - I have a text file with more than 40,000,000 lines. It takes
	  - VIM very long time to load. Is there anything I can do to make
	  - it quicker?

    You may want to investigate the common large-file solutions:

    http://www.vim.org/scripts/script.php?script_id=1506
    http://vim.wikia.com/wiki/Faster_loading_of_large_files

    Depending on your edits, you might have better luck using sed which will
    process it as a stream instead of trying to hold the whole thing in
    memory.  You might also want to read limits for limitations you might
    bump into with files that large.

    Additionally, with a file that large, it might be useful (if you're on
    *nix or have common *nix-utilities on Win32) to use the split/csplit
    commands to chop up your file into manageable bits to edit subsets of
    them, and then piece them all back together with cat.


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2. History						largefile-history {{{1

  7 :	Oct 30, 2014	* made saving and restoration use local or global
			  consistently (depends on vim version as to which
			  is used)
	Jan 08, 2015	* (Daniel Hahler) provided a patch to fix an error
			  that showed up while quitting a large buffer
  5 :	Aug 19, 2009	* Largefile additionally disables folding and parentheses
			  matching (:Unlarge will restore them)
			* complete option set so that buffers from other windows
			  are not scanned.  Thus an open "Large" file will not
			  cause completion to run slow in other windows.
			  Unfortunately I see no way to have just the "Large"
			  buffers bypassed this way; its either all or none.
	Jan 20, 2011	* Changed setting retention variables to use a
			  common "b:LF_" prefix
	Apr 24, 2013	* (Kris Malfettone) suggested that 'bk' and 'wk'
			  options should also be suppressed by LargeFile.
	Oct 31, 2013	* persistent undo used to localize turning
			  'undolevels' off to LargeFiles
  4 :	Jan 03, 2008	* made LargeFile.vim :AutoInstall:-able by getscript
	Apr 11, 2008	* (Daniel Shahaf suggested) that :Large! do the large-file
			  handling irregardless of file size.  Implemented.
	Sep 23, 2008	* if getfsize() returns -2 then the file is assumed to be
			  large
  3 :	May 24, 2007	* Unlarge command included
			* If getfsize() returns something less than -1, then it
			  will automatically be assumed to be a large file.

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vim:tw=78:ts=8:ft=help:fdm=marker: