shell programming file creation date
1. Please write a script named sh01.sh, which is:
Keyboard input file name (requires the use of spelling the name as the file name).
Automatically create three files.
A system for the current date (CCYYMMDD).
A date is one day before the system.
A date for the former system of the two.
Server configuration for Web Server on virtual machines
1.rpm –qa | grep httpd
2.命令：yum install httpd –y
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