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1
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2 @node Basic, Undo, Startup Paths, Top
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3 @chapter Basic Editing Commands
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4
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5 @kindex C-h t
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6 @findex help-with-tutorial
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7 We now give the basics of how to enter text, make corrections, and
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8 save the text in a file. If this material is new to you, you might
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9 learn it more easily by running the Emacs learn-by-doing tutorial. To
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10 do this, type @kbd{Control-h t} (@code{help-with-tutorial}).
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11
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12 @section Inserting Text
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13
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14 @cindex insertion
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15 @cindex point
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16 @cindex cursor
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17 @cindex graphic characters
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18 To insert printing characters into the text you are editing, just type
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19 them. This inserts the characters into the buffer at the cursor (that
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20 is, at @dfn{point}; @pxref{Point}). The cursor moves forward. Any
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21 characters after the cursor move forward too. If the text in the buffer
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22 is @samp{FOOBAR}, with the cursor before the @samp{B}, and you type
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23 @kbd{XX}, the result is @samp{FOOXXBAR}, with the cursor still before the
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24 @samp{B}.
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25
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26 @kindex DEL
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27 @cindex deletion
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28 To @dfn{delete} text you have just inserted, use @key{DEL}.
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29 @key{DEL} deletes the character @var{before} the cursor (not the one
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30 that the cursor is on top of or under; that is the character @var{after}
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31 the cursor). The cursor and all characters after it move backwards.
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32 Therefore, if you type a printing character and then type @key{DEL},
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33 they cancel out.
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34
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35 @kindex RET
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36 @cindex newline
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37 To end a line and start typing a new one, type @key{RET}. This
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38 inserts a newline character in the buffer. If point is in the middle of
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39 a line, @key{RET} splits the line. Typing @key{DEL} when the cursor is
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40 at the beginning of a line rubs out the newline before the line, thus
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41 joining the line with the preceding line.
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42
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43 Emacs automatically splits lines when they become too long, if you
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44 turn on a special mode called @dfn{Auto Fill} mode. @xref{Filling}, for
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45 information on using Auto Fill mode.
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46
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47 @findex delete-backward-char
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48 @findex newline
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49 @findex self-insert
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50 Customization information: @key{DEL}, in most modes, runs the command
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51 @code{delete-backward-char}; @key{RET} runs the command @code{newline},
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52 and self-inserting printing characters run the command
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53 @code{self-insert}, which inserts whatever character was typed to invoke
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54 it. Some major modes rebind @key{DEL} to other commands.
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55
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56 @cindex quoting
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57 @kindex C-q
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58 @findex quoted-insert
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59 Direct insertion works for printing characters and @key{SPC}, but
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60 other characters act as editing commands and do not insert themselves.
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61 If you need to insert a control character or a character whose code is
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62 above 200 octal, you must @dfn{quote} it by typing the character
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63 @kbd{control-q} (@code{quoted-insert}) first. There are two ways to use
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64 @kbd{C-q}:@refill
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65
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66 @itemize @bullet
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67 @item
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68 @kbd{Control-q} followed by any non-graphic character (even @kbd{C-g})
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69 inserts that character.
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70 @item
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71 @kbd{Control-q} followed by three octal digits inserts the character
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72 with the specified character code.
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73 @end itemize
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74
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75 @noindent
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76 A numeric argument to @kbd{C-q} specifies how many copies of the quoted
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77 character should be inserted (@pxref{Arguments}).
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78
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79 If you prefer to have text characters replace (overwrite) existing
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80 text instead of moving it to the right, you can enable Overwrite mode, a
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81 minor mode. @xref{Minor Modes}.
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82
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83 @section Changing the Location of Point
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84
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85 To do more than insert characters, you have to know how to move point
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86 (@pxref{Point}). Here are a few of the available commands.
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87
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88 NOTE: Many of the following commands have two versions, one that uses
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89 the function keys (e.g. @key{LEFT} or @key{END}) and one that doesn't.
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90 The former versions may only be available on X terminals (i.e. not on
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91 TTY's), but the latter are available on all terminals.
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92
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93 @kindex C-a
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94 @kindex C-e
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95 @kindex C-f
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96 @kindex C-b
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97 @kindex C-n
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98 @kindex C-p
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99 @kindex C-l
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100 @kindex C-t
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101 @kindex C-v
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102 @kindex M-v
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103 @kindex M->
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104 @kindex M-<
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105 @kindex M-r
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106 @kindex LEFT
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107 @kindex RIGHT
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108 @kindex UP
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109 @kindex DOWN
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110 @kindex HOME
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111 @kindex END
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112 @kindex PGUP
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113 @kindex PGDN
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114 @kindex C-LEFT
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115 @kindex C-RIGHT
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116 @kindex C-HOME
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117 @kindex C-END
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118 @findex beginning-of-line
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119 @findex end-of-line
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120 @findex forward-char
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121 @findex backward-char
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122 @findex next-line
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123 @findex previous-line
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124 @findex recenter
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125 @findex transpose-chars
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126 @findex beginning-of-buffer
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127 @findex end-of-buffer
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128 @findex goto-char
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129 @findex goto-line
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130 @findex move-to-window-line
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131 @table @kbd
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132 @item C-a
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133 @itemx HOME
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134 Move to the beginning of the line (@code{beginning-of-line}).
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135 @item C-e
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136 @itemx END
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137 Move to the end of the line (@code{end-of-line}).
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138 @item C-f
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139 @itemx RIGHT
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140 Move forward one character (@code{forward-char}).
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141 @item C-b
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142 @itemx LEFT
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143 Move backward one character (@code{backward-char}).
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144 @item M-f
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145 @itemx C-RIGHT
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146 Move forward one word (@code{forward-word}).
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147 @item M-b
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148 @itemx C-LEFT
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149 Move backward one word (@code{backward-word}).
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150 @item C-n
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151 @itemx DOWN
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152 Move down one line, vertically (@code{next-line}). This command attempts to keep the horizontal position unchanged, so if you start in the middle of one line, you end in the middle of the next. When on the last line of text, @kbd{C-n} creates a new line and moves onto it.
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153 @item C-p
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154 @itemx UP
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155 Move up one line, vertically (@code{previous-line}).
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156 @item C-v
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157 @itemx PGDN
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158 Move down one page, vertically (@code{scroll-up}).
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159 @item M-v
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160 @itemx PGUP
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161 Move up one page, vertically (@code{scroll-down}).
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162 @item C-l
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163 Clear the frame and reprint everything (@code{recenter}). Text moves
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164 on the frame to bring point to the center of the window.
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165 @item M-r
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166 Move point to left margin on the line halfway down the frame or
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167 window (@code{move-to-window-line}). Text does not move on the
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168 frame. A numeric argument says how many screen lines down from the
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169 top of the window (zero for the top). A negative argument counts from
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170 the bottom (@minus{}1 for the bottom).
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171 @item C-t
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172 Transpose two characters, the ones before and after the cursor
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173 @*(@code{transpose-chars}).
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174 @item M-<
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175 @itemx C-HOME
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176 Move to the top of the buffer (@code{beginning-of-buffer}). With
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177 numeric argument @var{n}, move to @var{n}/10 of the way from the top.
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178 @xref{Arguments}, for more information on numeric arguments.@refill
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179 @item M->
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180 @itemx C-END
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181 Move to the end of the buffer (@code{end-of-buffer}).
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182 @item M-x goto-char
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183 Read a number @var{n} and move the cursor to character number @var{n}.
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184 Position 1 is the beginning of the buffer.
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185 @item M-g
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186 Read a number @var{n} and move cursor to line number @var{n}
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187 (@code{goto-line}). Line 1 is the beginning of the buffer.
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188 @item C-x C-n
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189 @findex set-goal-column
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190 Use the current column of point as the @dfn{semi-permanent goal column} for
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191 @kbd{C-n} and @kbd{C-p} (@code{set-goal-column}). Henceforth, those
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192 commands always move to this column in each line moved into, or as
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193 close as possible given the contents of the line. This goal column remains
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194 in effect until canceled.
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195 @item C-u C-x C-n
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196 Cancel the goal column. Henceforth, @kbd{C-n} and @kbd{C-p} once
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197 again try to avoid changing the horizontal position, as usual.
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198 @end table
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199
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200 @vindex track-eol
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201 If you set the variable @code{track-eol} to a non-@code{nil} value,
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202 @kbd{C-n} and @kbd{C-p} move to the end of the line when at the end of
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203 the starting line. By default, @code{track-eol} is @code{nil}.
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204
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205 @section Erasing Text
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206
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207 @table @kbd
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208 @item @key{DEL}
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209 Delete the character before the cursor (@code{delete-backward-char}).
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210 @item C-d
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211 Delete the character after the cursor (@code{delete-char}).
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212 @item C-k
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213 Kill to the end of the line (@code{kill-line}).
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214 @item M-d
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215 Kill forward to the end of the next word (@code{kill-word}).
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216 @item M-@key{DEL}
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217 Kill back to the beginning of the previous word
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218 (@code{backward-kill-word}).
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219 @end table
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220
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221 In contrast to the @key{DEL} key, which deletes the character before
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222 the cursor, @kbd{Control-d} deletes the character after the cursor,
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223 causing the rest of the text on the line to shift left. If
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224 @kbd{Control-d} is typed at the end of a line, that line and the next
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225 line are joined.
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226
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227 To erase a larger amount of text, use @kbd{Control-k}, which kills a
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228 line at a time. If you use @kbd{C-k} at the beginning or in the middle
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229 of a line, it kills all the text up to the end of the line. If you use
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230 @kbd{C-k} at the end of a line, it joins that line and the next
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231 line.
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232
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233 @xref{Killing}, for more flexible ways of killing text.
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234
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235 @section Files
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236
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237 @cindex files
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238 The commands above are sufficient for creating and altering text in an
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239 Emacs buffer. More advanced Emacs commands just make things easier. But
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240 to keep any text permanently you must put it in a @dfn{file}. Files are
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241 named units of text which are stored by the operating system and which
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242 you can retrieve by name. To look at or use the contents of a file in
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243 any way, including editing the file with Emacs, you must specify the
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244 file name.
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245
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246 Consider a file named @file{/usr/rms/foo.c}. To begin editing
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247 this file from Emacs, type:
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248
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249 @example
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250 C-x C-f /usr/rms/foo.c @key{RET}
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251 @end example
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252
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253 @noindent
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254 The file name is given as an @dfn{argument} to the command @kbd{C-x
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255 C-f} (@code{find-file}). The command uses the @dfn{minibuffer} to
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256 read the argument. You have to type @key{RET} to terminate the argument
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257 (@pxref{Minibuffer}).@refill
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258
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259 You can also use the @b{Open...} menu item from the @b{File} menu, then
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260 type the name of the file to the prompt.
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261
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262 Emacs obeys the command by @dfn{visiting} the file: it creates a
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263 buffer, copies the contents of the file into the buffer, and then
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264 displays the buffer for you to edit. You can make changes in the
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265 buffer, and then @dfn{save} the file by typing @kbd{C-x C-s}
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266 (@code{save-buffer}) or choosing @b{Save Buffer} from the @b{File} menu.
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267 This makes the changes permanent by copying the altered contents of the
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268 buffer back into the file @file{/usr/rms/foo.c}. Until then, the
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269 changes are only inside your Emacs buffer, and the file @file{foo.c} is
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270 not changed.@refill
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271
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272 To create a file, visit the file with @kbd{C-x C-f} as if it already
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273 existed or choose @b{Open...} from the @b{File} menu and provide the
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274 name for the new file in the minibuffer. Emacs will create an empty
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275 buffer in which you can insert the text you want to put in the file.
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276 When you save the buffer with @kbd{C-x C-s}, or by choosing @b{Save
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277 Buffer} from the @b{File} menu, the file is created.
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278
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279 To learn more about using files, @pxref{Files}.
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280
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281 @section Help
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282
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283 If you forget what a key does, you can use the Help character
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284 (@kbd{C-h}) to find out: Type @kbd{C-h k} followed by the key you want
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285 to know about. For example, @kbd{C-h k C-n} tells you what @kbd{C-n}
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286 does. @kbd{C-h} is a prefix key; @kbd{C-h k} is just one of its
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287 subcommands (the command @code{describe-key}). The other subcommands of
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288 @kbd{C-h} provide different kinds of help. Type @kbd{C-h} three times
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289 to get a description of all the help facilities. @xref{Help}.@refill
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290
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291 @menu
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292 * Blank Lines:: Commands to make or delete blank lines.
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293 * Continuation Lines:: Lines too wide for the frame.
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294 * Position Info:: What page, line, row, or column is point on?
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295 * Arguments:: Numeric arguments for repeating a command.
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296 @end menu
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297
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298 @node Blank Lines, Continuation Lines, Basic, Basic
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299 @section Blank Lines
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300
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301 Here are special commands and techniques for entering and removing
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302 blank lines.
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303
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304 @c widecommands
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305 @table @kbd
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306 @item C-o
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307 Insert one or more blank lines after the cursor (@code{open-line}).
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308 @item C-x C-o
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309 Delete all but one of many consecutive blank lines
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310 (@code{delete-blank-lines}).
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311 @end table
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312
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313 @kindex C-o
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314 @kindex C-x C-o
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315 @cindex blank lines
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316 @findex open-line
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317 @findex delete-blank-lines
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318 When you want to insert a new line of text before an existing line,
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319 you just type the new line of text, followed by @key{RET}. If you
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320 prefer to create a blank line first and then insert the desired text,
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321 use the key @kbd{C-o} (@code{open-line}), which inserts a newline after
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322 point but leaves point in front of the newline. Then type
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323 the text into the new line. @kbd{C-o F O O} has the same effect as
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324 @kbd{F O O @key{RET}}, except for the final location of point.
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325
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326 To create several blank lines, type @kbd{C-o} several times, or
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327 give @kbd{C-o} an argument indicating how many blank lines to create.
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328 @xref{Arguments}, for more information.
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329
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330 If you have many blank lines in a row and want to get rid of them, use
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331 @kbd{C-x C-o} (@code{delete-blank-lines}). If point is on a blank
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332 line which is adjacent to at least one other blank line, @kbd{C-x C-o}
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333 deletes all but one of the blank lines.
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334 If point is on a blank line with no other adjacent blank line, the
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335 sole blank line is deleted. If point is on a non-blank
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336 line, @kbd{C-x C-o} deletes any blank lines following that non-blank
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337 line.
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338
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339 @node Continuation Lines, Position Info, Blank Lines, Basic
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340 @section Continuation Lines
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341
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342 @cindex continuation line
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343 If you add too many characters to one line without breaking with a
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344 @key{RET}, the line grows to occupy two (or more) screen lines, with a
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345 curved arrow at the extreme right margin of all but the last line. The
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346 curved arrow indicates that the following screen line is not really a
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347 distinct line in the text, but just the @dfn{continuation} of a line too
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348 long to fit the frame. You can use Auto Fill mode (@pxref{Filling})
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349 to have Emacs insert newlines automatically when a line gets too long.
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350
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351
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352 @vindex truncate-lines
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353 @cindex truncation
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354 Instead of continuation, long lines can be displayed by @dfn{truncation}.
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355 This means that all the characters that do not fit in the width of the
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356 frame or window do not appear at all. They remain in the buffer,
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357 temporarily invisible. Three diagonal dots in the last column (instead of
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358 the curved arrow inform you that truncation is in effect.
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359
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360 To turn off continuation for a particular buffer, set the
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361 variable @code{truncate-lines} to non-@code{nil} in that buffer.
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362 Truncation instead of continuation also happens whenever horizontal
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363 scrolling is in use, and optionally whenever side-by-side windows are in
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364 use (@pxref{Windows}). Altering the value of @code{truncate-lines} makes
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365 it local to the current buffer; until that time, the default value is in
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366 effect. The default is initially @code{nil}. @xref{Locals}.@refill
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367
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368 @node Position Info, Arguments, Continuation Lines, Basic
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369 @section Cursor Position Information
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370
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371 If you are accustomed to other display editors, you may be surprised
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372 that Emacs does not always display the page number or line number of
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373 point in the mode line. In Emacs, this information is only rarely
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374 needed, and a number of commands are available to compute and print it.
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375 Since text is stored in a way that makes it difficult to compute the
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376 information, it is not displayed all the time.
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377
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378 @table @kbd
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379 @item M-x what-page
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380 Print page number of point, and line number within page.
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381 @item M-x what-line
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382 Print line number of point in the buffer.
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383 @item M-=
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384 Print number of lines and characters in the current region
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385 (@code{count-lines-region}).
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386 @item C-x =
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387 Print character code of character after point, character position of
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388 point, and column of point (@code{what-cursor-position}).
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389 @end table
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390
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391 @findex what-page
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392 @findex what-line
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393 @cindex line number
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394 @cindex page number
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395 @kindex M-=
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396 @findex count-lines-region
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397
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398 There are several commands for printing line numbers:
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399 @itemize @bullet
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400 @item
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401 @kbd{M-x what-line} counts lines from the beginning of the file and
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402 prints the line number point is on. The first line of the file is line
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403 number 1. You can use these numbers as arguments to @kbd{M-x
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404 goto-line}.
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405 @item
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406 @kbd{M-x what-page} counts pages from the beginning of the file, and
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407 counts lines within the page, printing both of them. @xref{Pages}, for
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408 the command @kbd{C-x l}, which counts the lines in the current page.
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409 @item
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410 @kbd{M-=} (@code{count-lines-region}) prints the number of lines in
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411 the region (@pxref{Mark}).
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412 @end itemize
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413
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414 @kindex C-x =
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415 @findex what-cursor-position
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416 The command @kbd{C-x =} (@code{what-cursor-position}) provides
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417 information about point and about the column the cursor is in.
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418 It prints a line in the echo area that looks like this:
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419
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420 @example
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421 Char: x (0170) point=65986 of 563027(12%) column 44
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422 @end example
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423
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424 @noindent
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425 (In fact, this is the output produced when point is before @samp{column 44}
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426 in the example.)
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427
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428 The two values after @samp{Char:} describe the character following point,
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429 first by showing it and second by giving its octal character code.
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430
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431 @samp{point=} is followed by the position of point expressed as a character
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432 count. The front of the buffer counts as position 1, one character later
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433 as 2, and so on. The next, larger number is the total number of characters
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434 in the buffer. Afterward in parentheses comes the position expressed as a
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435 percentage of the total size.
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436
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437 @samp{column} is followed by the horizontal position of point, in columns
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438 from the left edge of the window.
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439
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440 If the buffer has been narrowed, making some of the text at the
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441 beginning and the end temporarily invisible, @kbd{C-x =} prints
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442 additional text describing the current visible range. For example, it
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443 might say:
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444
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445 @smallexample
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446 Char: x (0170) point=65986 of 563025(12%) <65102 - 68533> column 44
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447 @end smallexample
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448
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449 @noindent
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450 where the two extra numbers give the smallest and largest character position
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451 that point is allowed to assume. The characters between those two positions
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452 are the visible ones. @xref{Narrowing}.
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453
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454 If point is at the end of the buffer (or the end of the visible part),
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455 @kbd{C-x =} omits any description of the character after point.
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456 The output looks like
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457
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458 @smallexample
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459 point=563026 of 563025(100%) column 0
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460 @end smallexample
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461
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462 @node Arguments,, Position Info, Basic
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463 @section Numeric Arguments
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464 @cindex numeric arguments
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465
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466 Any Emacs command can be given a @dfn{numeric argument}. Some commands
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467 interpret the argument as a repetition count. For example, giving an
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468 argument of ten to the key @kbd{C-f} (the command @code{forward-char}, move
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469 forward one character) moves forward ten characters. With these commands,
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470 no argument is equivalent to an argument of one. Negative arguments are
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471 allowed. Often they tell a command to move or act backwards.
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472
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473 @kindex M-1
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474 @kindex M-@t{-}
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475 @findex digit-argument
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476 @findex negative-argument
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477 If your keyboard has a @key{META} key (labelled with a diamond on
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478 Sun-type keyboards and labelled @samp{Alt} on some other keyboards), the
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479 easiest way to specify a numeric argument is to type digits and/or a
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480 minus sign while holding down the @key{META} key. For example,
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481 @example
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482 M-5 C-n
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483 @end example
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484 @noindent
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485 moves down five lines. The characters @kbd{Meta-1}, @kbd{Meta-2}, and
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486 so on, as well as @kbd{Meta--}, do this because they are keys bound to
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487 commands (@code{digit-argument} and @code{negative-argument}) that are
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488 defined to contribute to an argument for the next command.
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489
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490 @kindex C-u
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491 @findex universal-argument
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492 Another way of specifying an argument is to use the @kbd{C-u}
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493 (@code{universal-argument}) command followed by the digits of the argument.
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494 With @kbd{C-u}, you can type the argument digits without holding
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495 down shift keys. To type a negative argument, start with a minus sign.
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496 Just a minus sign normally means @minus{}1. @kbd{C-u} works on all terminals.
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497
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498 @kbd{C-u} followed by a character which is neither a digit nor a minus
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499 sign has the special meaning of ``multiply by four''. It multiplies the
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500 argument for the next command by four. @kbd{C-u} twice multiplies it by
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501 sixteen. Thus, @kbd{C-u C-u C-f} moves forward sixteen characters. This
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502 is a good way to move forward ``fast'', since it moves about 1/5 of a line
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503 in the usual size frame. Other useful combinations are @kbd{C-u C-n},
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504 @kbd{C-u C-u C-n} (move down a good fraction of a frame), @kbd{C-u C-u
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505 C-o} (make ``a lot'' of blank lines), and @kbd{C-u C-k} (kill four
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506 lines).@refill
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507
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508 Some commands care only about whether there is an argument and not about
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509 its value. For example, the command @kbd{M-q} (@code{fill-paragraph}) with
|
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510 no argument fills text; with an argument, it justifies the text as well.
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511 (@xref{Filling}, for more information on @kbd{M-q}.) Just @kbd{C-u} is a
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512 handy way of providing an argument for such commands.
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513
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514 Some commands use the value of the argument as a repeat count, but do
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515 something peculiar when there is no argument. For example, the command
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516 @kbd{C-k} (@code{kill-line}) with argument @var{n} kills @var{n} lines,
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517 including their terminating newlines. But @kbd{C-k} with no argument is
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518 special: it kills the text up to the next newline, or, if point is right at
|
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519 the end of the line, it kills the newline itself. Thus, two @kbd{C-k}
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520 commands with no arguments can kill a non-blank line, just like @kbd{C-k}
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521 with an argument of one. (@xref{Killing}, for more information on
|
|
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522 @kbd{C-k}.)@refill
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523
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524 A few commands treat a plain @kbd{C-u} differently from an ordinary
|
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525 argument. A few others may treat an argument of just a minus sign
|
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526 differently from an argument of @minus{}1. These unusual cases will be
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|
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527 described when they come up; they are always to make the individual
|
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528 command more convenient to use.
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529
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530 @c section Autoarg Mode
|
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|
531 @ignore
|
|
|
532 @cindex autoarg mode
|
|
|
533 Users of ASCII keyboards may prefer to use Autoarg mode. Autoarg mode
|
|
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534 means that you don't need to type @kbd{C-u} to specify a numeric argument.
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535 Instead, you type just the digits. Digits followed by an ordinary
|
|
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536 inserting character are themselves inserted, but digits followed by an
|
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537 Escape or Control character serve as an argument to it and are not
|
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|
538 inserted. A minus sign can also be part of an argument, but only at the
|
|
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539 beginning. If you type a minus sign following some digits, both the digits
|
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540 and the minus sign are inserted.
|
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|
541
|
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542 To use Autoarg mode, set the variable Autoarg Mode nonzero.
|
|
|
543 @xref{Variables}.
|
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544
|
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545 Autoargument digits echo at the bottom of the frame; the first
|
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546 nondigit causes them to be inserted or uses them as an argument. To
|
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547 insert some digits and nothing else, you must follow them with a Space
|
|
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548 and then rub it out. @kbd{C-g} cancels the digits, while Delete inserts
|
|
|
549 them all and then rubs out the last.
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550 @end ignore
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