Difference between revisions of "Echo Command"

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echo "*** Backup wrote to $BACKUP/$NOW/latest.tar.gz"
 
echo "*** Backup wrote to $BACKUP/$NOW/latest.tar.gz"
 
</source>
 
</source>
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==Generating Output With printf command==
 +
printf command format and display data on screen. However, printf does not provide a new line. You need to provide format string using % directives and escapes to format numeric and string arguments in a way that is mostly similar to the C printf() function.
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===printf Command Examples===

Revision as of 19:03, 30 August 2009

To display the value of a variable either use echo or printf command as follows:

echo $varName

OR

printf "%s\n" $varName

Generating Output With echo command

Use echo command to display a line of text or variable value. It offer no formatting option. It is good command to display simple output.

echo Command Examples

#!/bin/bash
# Display welcome message, computer name and date
echo "*** Backup Shell Script ***"
echo
echo "*** Run time: $(date) @ $(hostname)"
echo

# Define variables
BACKUP="/nas05"
NOW=$(date +"%d-%m-%Y")
 
# Let us start backup
echo "*** Dumping MySQL Database to $BACKUP/$NOW..."

# Just sleep for 3 secs
sleep 3

# And we are done...
echo
echo "*** Backup wrote to $BACKUP/$NOW/latest.tar.gz"

Generating Output With printf command

printf command format and display data on screen. However, printf does not provide a new line. You need to provide format string using % directives and escapes to format numeric and string arguments in a way that is mostly similar to the C printf() function.

printf Command Examples