linux实验4-bash1
#!/bin/bash #set -xv function welcome() { echo "Use one of the following options:" echo "P: To display current directory" echo "S: To display the name of runing file" echo "D: To display today's date and present time" echo "L: To see the listing of files in your present working directory" echo "W: To see who is logged in" echo "Q: To quit this program" echo -n "Enter your option and hit:" read op } welcome until [ 'expr match "$op" "[Q|q]"'=="0" ]; #注意空格 do case "$op" in P|p) pwd echo "" welcome ;; S|s) echo "The running file is $0" echo "" welcome ;; D|d) date echo "" welcome ;; L|l) ls -a echo "" welcome ;; W|w) who echo "" welcome ;; *) echo -n "Error!Please enter option again:" read op esac done echo "BYE" exit 0
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