In this article, we will see how to print Good Morning, Good Afternoon, Good Evening, and Good Night, according to system time using shell programming

Example :

# Program to print Good Morning, 
# Good Afternoon, Good Evening 
$ and Good Night, according to
$  system time.


#!/bin/bash
hour=`date +%H`
if [ $hour -lt 12 ] # if hour is less than 12
then
echo "GOOD MORNING WORLD"
elif [ $hour -le 16 ] # if hour is less than equal to 16
then
echo "GOOD AFTERNOON WORLD"
elif [ $hour -le 20 ] # if hour is less than equal to 20
then
echo "GOOD EVENING WORLD"
else
echo "GOOD NIGHT WORLD"
fi

The above shell script displays “Good morning!”, “Good afternoon!”, “Good evening” or “Good night” based on the time it gets executed in the system. The program will have .sh extension. 

The variable “hour” will hold the value of `date +%H`. The command “date +%H” returns the hour in 24-hour format. The command “echo” will simply print the statement if it satisfies the condition.

Output :

 

Example 2:

#!/bin/bash
hour=$(date +%H)
if [ $hour -lt 12 ]
then 
greet="Good Morning"
elif [ $hour -le 16 ]
then
greet="Good Afternoon"
elif [ $hour -lt 20 ]
then
greet="Good Evening"
else
greet="Good Night"
fi
echo "$greet"

In this example, we have declared a new variable ‘greet’, which is holding “Good Morning”, “Good Afternoon”, “Good Evening” and “Good Night”. Depending on the time of the system, it will print Good morning, Good afternoon, Good Evening, or Good Night to the user.