What linux in the command?
Command is an executable binary program
Execute commands in several ways?
./test.sh # relative path execution
/data/test.sh # absolute path execution
source /data/test.sh # read execution
. /Data/test.sh # read execution
bash /data/test.sh # perform in sub-shell
How to create your own command?
First, create a script, here it is in many programmers just starting to learn the script code examples
[root@uplooking ~]# vim hello
#!/bin/bash echo "Hello World !"
Second, add execute permission to the script
[root@uplooking ~]# chmod u+x hello
Third, view the command storage location
[root@uplooking ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin
Fourth, copy the script to the next path, note that the above path just put a place like
[root@uplooking ~]# cp hello /usr/local/sbin/
Fifth, the output of the command
[root @ uplooking ~] # hello
hello world!