Linux学习笔记 1 环境变量 2 vi命令

1 环境变量篇

1.1 修改 查看 生效 系统环境变量

1 涉及系统环境变量的文件 --> .bash_profile

　　　　　　　　　　　　　　 -->　/etc/profile

2 该文件位置 /root/.bash_profile

3 文件编辑器打开 vi .bash_profile

4 文件末尾加入

JAVA_HOME = /usr/share/jdk 1.6.0
PATH = $JAVA_HOME/bin:$PATH
CLASS_PATH=.$JAVA_HOME/lib/dt.jar：
$JAVA_HOME/lib/tools.jar

export JAVA_HOME
export PATH
export CLASSPATH

5 文件生效
source /root/.bash_profile
6 验证环境变量
export JAVA_HOME
echo $JAVA_HOME

VI 命令篇章
输入指令 a
退出指令 :q  强退：q!   保存且退出 :wq
存成新文件  :w newfile

查找指令  : ？____   <要查找的单词>
/  ____  要查的词
n    finding the dedicate word then moving to the next
N    oppersite direction
:set nu <---show the line number
:set nonu <---remove line number

direction :
k
h   j  l

input: i  insert in front of the cursor
a insert behind the cursor
o  insert in the next line of the cursor

delete:
x:delete the char of the cursor
X :delete the char of the cursor

dd:delete the current row
5dd:delete the currrent line and the next 5 line
:1,5d delete1 to 5 line
x delete one charactor

vi substitute
:s /cici/titi         replace the line cici with titi
:s/cici/titi/g       replace all the cici with titi in the current line
:n,$s/cici/titi    the line n to the last line.each line cici replace with titi
:n,$s /cici/titi/g  the line n to the last line.each line cici replace with titi
:.,$s/cici/titi     replace all the words in the passages from the first line
to the last line

repalce confirmation command.adding character c behind the comma

:s/cici/titi/gc  all the cici replace with titi  + confirmation
show line number :set nu

dw  delete current words
3dw delete 3 words

copy and attach

yw  copy word
y5w copy all 5 words
yy copy all the line
5yy copy 5 lines
p copy after the current line
:1,2co3 copy from line1 to line2 after line 3
:4,5m6
1          1
2          2
3          3
4          6
5          4
6          5

location command
gg moving to the front of the file
G moving to the end of file
:20 moving to line 20
J  merge 2 line
shift + 8 :
finding the word which is in the position of cursor