Emacs快速入门

Bertha 。 2022-03-21 09:08 303阅读 0赞

# Emacs快速入门 #

Ubuntu初安装时，其时是有emacs图形界面和emacs终端界面两个快捷方式的。你只需要用鼠标点击就可以进入相应的模式。

不过如果你真心开始想用emacs，相信会有更便捷的方式，比如在终端输入emacs -nw，我们可以查emacs的帮助文档来看一眼这个-nw参数是什么意思（--no-window-system, -nw），如下

打开emacs的帮助文档：emacs --help

另外对于emacs，我想说的是，其实常用的命令并不多，花几小时就能熟悉，熟练掌握也不难，但需要经常使用，不然肯定会忘记掉。

emacs --help
    Usage: emacs [OPTION-OR-FILENAME]...
    
    Run Emacs, the extensible, customizable, self-documenting real-time
    display editor.  The recommended way to start Emacs for normal editing
    is with no options at all.
    
    Run M-x info RET m emacs RET m emacs invocation RET inside Emacs to
    read the main documentation for these command-line arguments.
    
    Initialization options:
    
    --batch                     do not do interactive display; implies -q
    --chdir DIR                 change to directory DIR
    --daemon                    start a server in the background
    --debug-init                enable Emacs Lisp debugger for init file
    --display, -d DISPLAY       use X server DISPLAY
    --no-desktop                do not load a saved desktop
    --no-init-file, -q          load neither ~/.emacs nor default.el
    --no-loadup, -nl            do not load loadup.el into bare Emacs
    --no-site-file              do not load site-start.el
    --no-x-resources            do not load X resources
    --no-site-lisp, -nsl        do not add site-lisp directories to load-path
    --no-splash                 do not display a splash screen on startup
    --no-window-system, -nw     do not communicate with X, ignoring $DISPLAY
    --quick, -Q                 equivalent to:
                                  -q --no-site-file --no-site-lisp --no-splash
                                  --no-x-resources
    --script FILE               run FILE as an Emacs Lisp script
    --terminal, -t DEVICE       use DEVICE for terminal I/O
    --user, -u USER             load ~USER/.emacs instead of your own
    
    Action options:
    
    FILE                    visit FILE using find-file
    +LINE                   go to line LINE in next FILE
    +LINE:COLUMN            go to line LINE, column COLUMN, in next FILE
    --directory, -L DIR     prepend DIR to load-path (with :DIR, append DIR)
    --eval EXPR             evaluate Emacs Lisp expression EXPR
    --execute EXPR          evaluate Emacs Lisp expression EXPR
    --file FILE             visit FILE using find-file
    --find-file FILE        visit FILE using find-file
    --funcall, -f FUNC      call Emacs Lisp function FUNC with no arguments
    --insert FILE           insert contents of FILE into current buffer
    --kill                  exit without asking for confirmation
    --load, -l FILE         load Emacs Lisp FILE using the load function
    --visit FILE            visit FILE using find-file
    
    Display options:
    
    --background-color, -bg COLOR   window background color
    --basic-display, -D             disable many display features;
                                      used for debugging Emacs
    --border-color, -bd COLOR       main border color
    --border-width, -bw WIDTH       width of main border
    --color, --color=MODE           override color mode for character terminals;
                                      MODE defaults to `auto', and
                                      can also be `never', `always',
                                      or a mode name like `ansi8'
    --cursor-color, -cr COLOR       color of the Emacs cursor indicating point
    --font, -fn FONT                default font; must be fixed-width
    --foreground-color, -fg COLOR   window foreground color
    --fullheight, -fh               make the first frame high as the screen
    --fullscreen, -fs               make the first frame fullscreen
    --fullwidth, -fw                make the first frame wide as the screen
    --maximized, -mm                make the first frame maximized
    --geometry, -g GEOMETRY         window geometry
    --no-bitmap-icon, -nbi          do not use picture of gnu for Emacs icon
    --iconic                        start Emacs in iconified state
    --internal-border, -ib WIDTH    width between text and main border
    --line-spacing, -lsp PIXELS     additional space to put between lines
    --mouse-color, -ms COLOR        mouse cursor color in Emacs window
    --name NAME                     title for initial Emacs frame
    --no-blinking-cursor, -nbc      disable blinking cursor
    --reverse-video, -r, -rv        switch foreground and background
    --title, -T TITLE               title for initial Emacs frame
    --vertical-scroll-bars, -vb     enable vertical scroll bars
    --xrm XRESOURCES                set additional X resources
    --parent-id XID                 set parent window
    --help                          display this help and exit
    --version                       output version information and exit
    
    You can generally also specify long option names with a single -; for
    example, -batch as well as --batch.  You can use any unambiguous
    abbreviation for a --option.
    
    Various environment variables and window system resources also affect
    the operation of Emacs.  See the main documentation.
    
    Report bugs to bug-gnu-emacs@gnu.org.  First, please see the Bugs
    section of the Emacs manual or the file BUGS.

## Emacs命令的格式 ##

通常你可以找到一些emacs的cheat sheet，这里面会有大量的命令描述，所以弄清楚这些命令代表哪些按键是最基本的要求，最常用的组合通常有下面这些，

*  C-n ：最常用的命令格式（n为任意字符）
 *  ESC n ：次常用的命令格式（n为任意字符）
 *  C-x something ： （通常为文件操作类）
 *  C-c something ： （通常与某些特殊的编辑模式有关）

按键             含义  
C-g              表示Ctrl+g组合键，即C代表Crtl  
RETURN     回车键，即enter  
META          ESC(或Alt)键  
ESC x         先按下ESC，再按下x键，注意先后顺序  
S-right        按下shift键，同时按下按下鼠标右键  
C-S-right    按下shift键，同时按下ctrl键和鼠标右键

注：

*  每个emacs都有完整的名字，如：forward-word命令即按下ESC f
 *  当发现一个命令有全名，却没有对应的按键时，可以先输入ESC x，再输入相应的全名，回车后即执行。
 *  META键很特殊，在sun工作站上空格两边即为此按键，但是在大多数键盘上这个按键并不存在，其功能基本上与ESC等价，在某些键盘上与Alt通用。
 *  META与ESC的区别在于：
    
     *  META的组合命令在按键的同时输入，同时放开键
     *  ESC的组合命令先按ESC，松开后输入其余内容。

## Emacs打开方式 ##

（图形界面） 在终端界面输入：

$ emacs hello.c   或   $ emacs

如果你想要在终端使用字符界面，如前所述，在终端界面输入：

$ emacs -nw hello.c

即可。

--------------------

## 常用的命令 ##

常用的命令这里只列一下，其实你只要在网上搜索emacs cheatsheet就可以找到这些ＰＤＦ文件，当然也有emacs cheatsheet的墙纸。下面这个链接就提供了不少漂亮的墙纸，你可以根据你的电脑显示器的尺寸去下载，做桌面也是挺不错的，

[https://www.emacswiki.org/emacs/EmacsWallpaper][https_www.emacswiki.org_emacs_EmacsWallpaper]  
(资料：[https://www.emacswiki.org/emacs/CategoryReferenceSheet][https_www.emacswiki.org_emacs_CategoryReferenceSheet])

顺便说一下，emacswiki（[https://www.emacswiki.org/emacs][https_www.emacswiki.org_emacs]）是个非常不错的中文学习网站。

**`M-x cd：切换`当前工作目录(这个命令cheatsheet里居然没有，特别列出来)**

`一般情况下，当使用‘C-x C-f’命令时，你看到的是` home directory，如果要切换目录，请使用“M-x cd”命令

如果你要设定emacs的启动目录，可以使用command-line-default-directory，我的\`.emacs\`配置文件看起就是这样的

(custom-set-variables
     ;; the below lines are for color theme setting
     '(ansi-color-faces-vector
       [default default default italic underline success warning error])
     '(ansi-color-names-vector
       ["#2e3436" "#a40000" "#4e9a06" "#c4a000" "#204a87" "#5c3566" "#729fcf" "#eeeeec"])
     '(custom-enabled-themes (quote (wheatgrass))))
    
    (custom-set-faces)
    
    (setq command-line-default-directory "~/devc/emacsdir" )

下面我象征性地列一下各个命令，这些命令的原文的地址在：[https://www.ast.cam.ac.uk/~vasily/idl/emacs\_commands\_list.html][https_www.ast.cam.ac.uk_vasily_idl_emacs_commands_list.html]

C = Control
    M = Meta = Alt|Esc
    
    Basics
    C-x C-f "find" file i.e. open/create a file in buffer
    C-x C-s save the file
    C-x C-w write the text to an alternate name
    C-x C-v find alternate file
    C-x i insert file at cursor position
    C-x b create/switch buffers
    C-x C-b show buffer list
    C-x k kill buffer
    C-z suspend emacs 
    C-X C-c close down emacs
    
    Basic movement
    C-f forward char
    C-b backward char
    C-p previous line
    C-n next line
    M-f forward one word
    M-b backward one word
    C-a beginning of line
    C-e end of line
    C-v one page up
    M-v scroll down one page
    M-< beginning of text
    M-> end of text
    
    Editing
    M-n repeat the following command n times
    C-u repeat the following command 4 times
    C-u n repeat n times
    C-d delete a char
    M-d delete word
    M-Del delete word backwards
    C-k kill line
    
    C-Space Set beginning mark (for region marking for example)
    C-W "kill" (delete) the marked region region
    M-W copy the marked region
    C-y "yank" (paste) the copied/killed region/line
    M-y yank earlier text (cycle through kill buffer)
    C-x C-x exchange cursor and mark
    
    C-t transpose two chars
    M-t transpose two words
    C-x C-t transpose lines
    M-u make letters uppercase in word from cursor position to end
    M-c simply make first letter in word uppercase
    M-l opposite to M-u
    
    Important
    C-g quit the running/entered command
    C-x u undo previous action
    M-x revert-buffer RETURN (insert like this) undo all changes since last save
    M-x recover-file RETURN Recover text from an autosave-file
    M-x recover-session RETURN if you edited several files
    
    Online-Help
    C-h c which command does this keystroke invoke
    C-h k which command does this keystroke invoke and what does it do?
    C-h l what were my last 100 typed keys
    C-h w what key-combo does this command have?
    C-h f what does this function do
    C-h v what's this variable and what is it's value
    C-h b show all keycommands for this buffer
    C-h t start the emacs tutorial
    C-h i start the info reader
    C-h C-k start up info reader and go to a certain key-combo point
    C-h F show the emacs FAQ
    C-h p show infos about the Elisp package on this machine
    
    Search/Replace
    C-s Search forward
    C-r search backward
    C-g return to where search started (if you are still in search mode)
    M-% query replace
    Space or y replace this occurence
    Del or n don't replace
    . only replace this and exit (replace)
    , replace and pause (resume with Space or y)
    ! replace all following occurences
    ^ back to previous match
    RETURN or q quit replace
    
    
    Search/Replace with regular expressions
    Characters to use in regular expressions:
    ^ beginning of line
    $ end of line
    . single char
    .* group or null of chars
    \< beginning of a word
    \> end of a word
    [] every char inside the backets (for example [a-z] means every small letter)
    
    M C-s RETURN search for regular expression forward
    M C-r RETURN search for regular expression backward
    M C-s incremental search
    C-s repeat incremental search
    M C-r incremental search backwards
    C-r repeat backwards
    M-x query-replace-regexp search and replace
    
    Window-Commands
    C-x 2 split window vertically
    C-x o change to other window
    C-x 0 delete window
    C-x 1 close all windows except the one the cursors in
    C-x ^ enlarge window
    M-x shrink-window command says it ;-)
    M C-v scroll other window
    C-x 4 f find file in other window
    C-x 4 o change to other window
    C-x 4 0 kill buffer and window
    C-x 5 2 make new frame
    C-x 5 f find file in other frame
    C-x 5 o change to other frame
    C-x 5 0 close this frame
    
    Bookmark commands
    C-x r m set a bookmark at current cursor pos
    C-x r b jump to bookmark
    M-x bookmark-rename says it
    M-x bookmark-delete "
    M-x bookmark-save "
    C-x r l list bookmarks
    d mark bookmark for deletion
    r rename bookmark
    s save all listed bookmarks
    f show bookmark the cursor is over
    m mark bookmarks to be shown in multiple window
    v show marked bookmarks (or the one the cursor is over)
    t toggle listing of the corresponding paths
    w " path to this file
    x delete marked bookmarks
    Del ?
    q quit bookmark list
    
    
    M-x bookmark-write write all bookmarks in given file
    M-x bookmark-load load bookmark from given file
    
    Shell
    M-x shell starts shell modus
    C-c C-c same as C-c under unix (stop running job)
    C-d delete char forward
    C-c C-d Send EOF
    C-c C-z suspend job (C-z under unix)
    M-p show previous commands
    
    DIRectory EDitor (dired)
    C-x d start up dired
    C (large C) copy 
    d mark for erase
    D delete right away
    e or f open file or directory
    g reread directory structure from file
    G change group permissions (chgrp)
    k delete line from listing on screen (don't actually delete)
    m mark with *
    n move to next line
    o open file in other window and go there
    C-o open file in other window but don't change there
    P print file
    q quit dired
    Q do query-replace in marked files
    R rename file
    u remove mark
    v view file content
    x delete files marked with D
    z compress file
    M-Del remove all marks (whatever kind)
    ~ mark backup files (name~ files) for deletion
    # mark auto-save files (#name#) for deletion
    */ mark directory with * (C-u * removes that mark again)
    = compare this file with marked file
    M-= compare this file with it's backup file
    ! apply shell command to this file
    M-} change to the next file marked with * od D
    M-{ " previous "
    % d mark files described through regular expression for deletion
    % m " (with *)
    + create directory
    > changed to next dir
    < change to previous dir
    s toggle between sorting by name or date
    
    Maybe into this category also fits this command:
    M-x speedbar starts up a separate window with a directory view
    
    Telnet
    M-x telnet starts up telnet-modus
    C-d either delete char or send EOF
    C-c C-c stop running job (similar to C-c under unix)
    C-c C-d send EOF
    C-c C-o clear output of last command
    C-c C-z suspend execution of command
    C-c C-u kill line backwards
    M-p recall previous command
    
    Text
    Works only in text mode 
    M-s center line
    M-S center paragraph
    M-x center-region name says 
    
    Macro-commands
    C-x ( start macro definition
    C-x ) end of macro definition
    C-x e execute last definied macro
    M-n C-x e execute last defined macro n times
    M-x name-last-kbd-macro give name to macro (for saving)
    M-x insert-keyboard-macro save named macro into file
    M-x load-file load macro
    M-x macroname execute macroname
    
    Programming
    M C-\ indent region between cursor and mark
    M-m move to first (non-space) char in this line
    M-^ attach this line to previous
    M-; formatize and indent comment
    C, C++ and Java Modes
    M-a beginning of statement
    M-e end of statement
    M C-a beginning of function
    M C-e end of function
    C-c RETURN Set cursor to beginning of function and mark at the end
    C-c C-q indent the whole function according to indention style
    C-c C-a toggle modus in which after electric signs (like {}:';./*) emacs does the indention
    C-c C-d toggle auto hungry mode in which emacs deletes groups of spaces with one del-press
    C-c C-u go to beginning of this preprocessor statement
    C-c C-c comment out marked area
    More general (I guess)
    M-x outline-minor-mode collapses function definitions in a file to a mere {...} 
    M-x show-subtree If you are in one of the collapsed functions, this un-collapses it 
    In order to achive some of the feats coming up now you have to run etags *.c *.h *.cpp (or what ever ending you source files have) in the source directory
    M-. (Thats Meta dot) If you are in a function call, this will take you to it's definition 
    M-x tags-search ENTER Searches through all you etaged 
    M-, (Meta comma) jumps to the next occurence for tags-search 
    M-x tags-query-replace yum. This lets you replace some text in all the tagged files 
    
    
    GDB (Debugger)
    M-x gdb starts up gdm in an extra window
    
    Version Control
    C-x v d show all registered files in this dir
    C-x v = show diff between versions
    C-x v u remove all changes since last checkin
    C-x v ~ show certain version in different window
    C-x v l print log
    C-x v i mark file for version control add
    C-x v h insert version control header into file
    C-x v r check out named snapshot
    C-x v s create named snapshot
    C-x v a create changelog file in gnu-style

## Emacs cheatsheet Wallpaper ##

这个墙纸前面提到了，我贴上来，由于分辨率是1920x1080的原因，只能下载后才能看清楚内容  
![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3Rhbm14MjE5_size_16_color_FFFFFF_t_70][]

[https_www.emacswiki.org_emacs_EmacsWallpaper]: https://www.emacswiki.org/emacs/EmacsWallpaper
[https_www.emacswiki.org_emacs_CategoryReferenceSheet]: https://www.emacswiki.org/emacs/CategoryReferenceSheet
[https_www.emacswiki.org_emacs]: https://www.emacswiki.org/emacs
[https_www.ast.cam.ac.uk_vasily_idl_emacs_commands_list.html]: https://www.ast.cam.ac.uk/~vasily/idl/emacs_commands_list.html
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3Rhbm14MjE5_size_16_color_FFFFFF_t_70]: /images/20220321/44d60645d61f413a9b7b7539027eddb0.png