What is vimrc?Edit

The vimrc file contains optional runtime configuration settings to initialize Vim when it starts. On Unix based systems, the file is named .vimrc, while on Windows systems it is named _vimrc. :help vimrc

You can customize Vim by putting suitable commands in your vimrc. Here is a very simple example:

" Always wrap long lines:
set wrap

Lines that begin with " are comments and are not read by vim.

Search for file vimrc_example.vim in your Vim files for another example. :help vimrc-intro:help vimrc_example.vim

To customize Vim for editing a specific file, or a specific type of file, you can usemodelines, or auto commands, or filetype plugins. :help auto-setting :help filetype

Location of vimrcEdit

In Vim, your home directory is specified with $HOME. On Unix systems, this is your ~directory. On Windows systems, the best way to find the value of $HOME is from within Vim, as follows. These commands are useful to see what directories your Vim is using:

:version
:echo expand(‘~‘)
:echo $HOME
:echo $VIM
:echo $VIMRUNTIME

Note the ‘system vimrc file‘ and ‘user vimrc file‘ paths displayed by the :versioncommand. The system vimrc file can be created by an administrator to customize Vim for all users. In addition, each user can have his or her own user vimrc.

The output from :version includes the paths of the system and user vimrc and gvimrc files. For example:

   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
      user exrc file: "$HOME/.exrc"
  system gvimrc file: "$VIM/gvimrc"
    user gvimrc file: "$HOME/.gvimrc"

If the gvimrc files exist, they are used to configure Vim when the GUI version (gvim) runs (after settings from vimrc are applied).

Settings for gvim can also be placed in the vimrc file using a has(‘gui_running‘) check:

if has(‘gui_running‘)
  set guioptions-=T  " no toolbar
  colorscheme elflord
endif

Although this can be useful to avoid the clutter of both a vimrc and gvimrc file, using the gvimrc file has distinct benefits over the "gui_running" check. The most notable being that a gvimrc file is sourced when using the :gui command to change a vim session into a gvim session. Anything that was in the vimrc inside a "gui_running" check will not be applied since the vimrc is only sourced when Vim initially starts.

Per-directory vimrcEdit

Vim can be configured so that, when starting, it reads commands from a vimrc file in the current directory, after reading the primary vimrc. This is configured by adding set exrcto the primary vimrc file. Setting ‘exrc‘ can be a security problem because it means Vim will execute commands from any vimrc file in the directory where Vim is started.:help ‘exrc‘ For that reason, set the ‘secure‘ option if you use this option, and you may also want to limit setting this option to when Vim is started from known "safe" directory trees:

if getcwd()~=#‘^\(/my/safe/dir1/\|/my/safe/dir2/\)‘
  set secure exrc
endif

Opening vimrcEdit

If Vim finds your vimrc file during startup, Vim will set the MYVIMRC environment variable to the full path of the vimrc file. Similarly, if your gvimrc file is found, the MYGVIMRCvariable is set. Therefore, you can easily edit these files from within Vim:

:e $MYVIMRC
:e $MYGVIMRC

Using file name completion, you could type :e $M then press Tab until you see the desired variable. If you only want to see the path, type :echo $M then press Tab to see the variable, and press Enter.

In gvim, the Edit menu includes "Startup Settings" which will use $MYVIMRC to edit your vimrc file. If $MYVIMRC does not exist, "Startup Settings" will create a new file using the "user vimrc file" path shown by the :version command.

Sourcing vimrcEdit

After you have saved changes to your vimrc file, you can see the results by exiting from Vim, then starting Vim again.

If you are making frequent changes, you might want to "source" (execute) the changed vimrc file without exiting:

:so $MYVIMRC
" Alternative that can be used if vimrc is the current file:
:so %

Warning You may need to plan your vimrc so re-sourcing does not cause problems. If you define commands, functions, or autocmds, you must make them remove or override the previous version when sourced, or you will get errors (for commands and functions) or duplicates (for autocmds). Here are some examples that will work correctly when re-sourced:

" Use bang (!) to redefine a command or function, if already defined.
command! Mycommand echo "Hello!"
function! Myfunc()
  echo "Hello!"
endfunction

" Put all autocmds in some augroup and use au! to clear the group.
augroup vimrc_autocmds
  au!
  autocmd BufRead * echo "File read!"
augroup END

Recovering from errorsEdit

Some errors in your vimrc may prevent Vim from starting successfully. A reliable way to handle that would be to rename your vimrc file, then edit the renamed file, then give it the correct name. Alternatively, you could start Vim with a command like this (or use "gvim" if that is how you run Vim):

vim -N -u NONE -U NONE

The -N starts in "not compatible" mode (that is, with extra Vim features). The NONEargument (must be uppercase) skips initializations and does not read any vimrc file (-u), and does not read any gvimrc file (-U).

You could now use the :version command to show the vimrc path, then enter a command to edit that file.

CommentsEdit

 TO DO 

• What else is needed to explain what vimrc is, and how to use it, for a beginner?
• Do something with the following text from the original tip (if keep it, need to fix text because it assumes you have used some standard setup for installation, and assumes $VIM and $HOME are some default, and of course is for Windows):

On Windows, when you start Vim normally, it *either* runs the file "C:\Documents and Settings\(user name)\_vimrc" (where "(user name)" is replaced by the actual user name); *or*, if that file doesn‘t exist (it usually doesn‘t, for most users), it runs the file "C:\Program Files\vim\_vimrc". Note that if you have more than one disk your home may be different; do an ":echo $HOME" to know where is your home. You should also see the _viminfo file in that directory.

• Include information for Windows:
  • When $HOME is not defined, it is created by combining $HOMEDRIVE and$HOMEPATH (if defined).
  • The recommended method to define $HOMEDRIVE and $HOMEPATH is to set the "Home folder ... Local path" on the Profile tab of the User properties in Local Users and Groups (run lusrmgr.msc).
  • I‘d say that this (the item above) is the recommended method to set your home folder in Windows. The recommendes method to specify where your _vimrc is located (if it differs from your home folder) is to set the $HOME environment variable. (Spiiph 00:16, 29 July 2009 (UTC))

• Link to the #vim-approved .vimrc? ;) (Spiiph 00:18, 29 July 2009 (UTC))

Proposal Omit suggestions like the following that attempt to auto-source vimrc. I suspect that anyone needing to read a tip to do this could get themselves in quite a bit of trouble. IMHO it‘s a lot more sensible to map a key to source a script so you can control when it is sourced. I haven‘t bothered to put such a mapping in the tip so far because the :so % info seems more helpful, and entirely adequate. --JohnBeckett 11:56, 23 August 2008 (UTC)

To source changes immediately, add to vimrc:

au BufLeave ~/.vimrc :source ~/.vimrc

Why not use a BufWritePost instead of BufLeave, so it will source whenever you save?

Getting started tip ... I hit this page because I could not remember the "mkvim" command. I found it elsewhere and thought I‘d throw it in here. If you open vim, change some settings and get things how you like you can use this command

:mkv [file]

to automatically make a vimrc file based on your current settings. The [file] part is optional; vim will use ~/.vimrc by default. If you already have a .vimrc and you attempt this you we will be warned that .vimrc already exists. You can use

mkv!

Using :mkvimrc to create .vimrc isn‘t a terribly good idea, since it saves mappings and abbreviations setup by plugins. It can be useful to copy currently set options to .vimrc however. (Spiiph 14:51, 27 July 2009 (UTC))

参考来源：http://vim.wikia.com/wiki/Open_vimrc_file

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