Rhcsa day 4

day04

File search 4 Ways of planting

whereis The query scope searches for files through the path of system environment variables $PATH, All documents

which The query scope searches for files through the path of system environment variables $PATH, Looking for executable （ Find command file ）

locate Global search , But you need to import the system files into the database before searching updatedb; Fast search speed

*find Global search for files .

matters needing attention ： 1）-prune It has to be with -path,-o Use it together 2）-prune -o The order is not Can exchange 3）-name Etc. must be placed in -prune -o You can use it later

！ -a -o

eg: find . -path ./tmp -prune -o -name "*.txt"

[[email protected] test]# find . ! -name "out" -a -name ".txt"

find / -name FILENAME -type f

find -name FILENAME

find ../.. -name FILENAME

-exec -ok

#-exec -ok find The result of finding the file is through The result of the previous command can be changed by default The line is recognized as multiple file parameters and processed by the following commands

find / -type f -exec cp -p {} /test \;

find / -type f -ok cp -p {} /test \;

[[email protected] test]# find . -type f |xargs -I {} cp {} /test

-I take xargs The name of each item of , It's usually assigned line by line to {}, It can be used {} Instead of .

File compression and decompression

tar

-c

-x

-t

-v

-f

-j

-J

-z

-C

File transfer ：

window --linux xftp Realize file transfer

rz FILENAME receive sz delivery ---lrzsz package

linux--linux

File sending ： scp mima [email protected]:/root

Documents received ： scp [email protected]:/root/mima /passwd

scp -r

[[email protected] ~]# sftp 192.168.220.154 launch sftp Remote connection for

sftp> put file

sftp> get filename

File management name

touch > >> vi/vim nano

mkdir

rm -rf

cp

mv

wget

cat tac more less head tail (vim nano) grep

vim nano > >>

echo this is test > a.txt

cat <<EOF > file

grep wc cut sort uniq tr

whereis

which

locate

find

tar

bash characteristic

alias Define command aliases

alias Alias =" Order itself "

l Temporary alias , It only takes effect when the current terminal is running

vim /etc/bashrc 1--exit 2--bash 3--source /etc/bashrc

The permanent alias is valid for all users of the system

vim ~/.bashrc

Permanent aliases are only valid for current use

Command cache

1. Build command cache

Execute the command to automatically create in the cache

hash -p /usr/bin/touch touch

hash -p /usr/bin/touch chuangjian

2. Delete cache

hash -d chuangjian

hash -r Empty all caches

exit terminal

Caching features ： Command cache ---alias-- Name order document

[[email protected] ~]# hash
hits    command
   3    /usr/bin/vim
   1    /usr/bin/cat
   1    /usr/sbin/pidof
   2    /usr/bin/su
[[email protected] ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin
[[email protected] ~]# which touch
/usr/bin/touch
[[email protected] ~]# touch a
[[email protected] ~]# hash
hits    command
   3    /usr/bin/vim
   1    /usr/bin/cat
   1    /usr/bin/touch
   1    /usr/sbin/pidof
   2    /usr/bin/su
[[email protected] ~]# touch /usr/bin/touch     ---= Priority through cache matching 
[[email protected] ~]# hash
hits    command
   3    /usr/bin/vim
   1    /usr/bin/cat
   2    /usr/bin/touch
   1    /usr/sbin/pidof
   2    /usr/bin/su
​
[[email protected] ~]# mv /usr/bin/touch /usr/local/bin
[[email protected] ~]# touch b
bash: /usr/bin/touch: No such file or directory
[[email protected] ~]# hash -d touch 
[[email protected] ~]# hash
hits    command
   3    /usr/bin/vim
   1    /usr/bin/cat
   1    /usr/sbin/pidof
   3    /usr/bin/mv
   2    /usr/bin/su
[[email protected] ~]# touch b     ---- There is no cache and the command file under the alias execution environment variable path 
[[email protected] ~]# hash -p /usr/bin/tac chakan    -- Alias 

history