Background

Had a Hard and Productive Heavy lifting with database work this weekend.

To lighten up the mood a bit, let us play around with Linux.

Hello World in Bash

Outline

1. Environment Variable
   • USER
     • Get Username by accessing the global variable $USER
     • Place it in the envUsername variable
2. System Variables
   • Get Date $(date)
     • Get Date Hours by accessing $(date +%H)
3. Depending on the hours get timeofDay
4. Display Salutation

Code

#!/bin/bash

envUsername=""
iDateHours=0
timeofDay=""

#######################################
# Get Environment variable
#######################################
envUsername=$USER

#######################################
# Date
#######################################
iDateHours=$(date +%H)

#echo "Date ( Hours):- $iDateHours"

##########################################
# Get Time of Day
##########################################
if [ "$iDateHours" -lt 12 ]; then

    timeofDay="morning"

elif [ "$iDateHours" -eq 12 ]; then

    timeofDay="noon"

elif [ "$iDateHours" -lt 17 ]; then

    timeofDay="afternoon"

elif [ "$iDateHours" -lt 21 ]; then

    timeofDay="evening"

else

    timeofDay="night"

fi

############################################
# Display username if available
############################################
if [ "$envUsername" = "" ]; then

   echo "Good $timeofDay"

else

   echo "$envUsername, Good $timeofDay"

fi

Output

Source Code Control

GitLab

HelloWorld In Languages

helloWorld.sh

Link