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Regex in Unix

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# 1  
Old 10-06-2010
Regex in Unix
user can enter Yes or yes or YES and its captured in variable say var

Code:
if [ $var == [Yy][Ee][Ss] ]
then
  #do something
elif [ $var == [Nn] [Oo] ]
then
  #do something

I think you got what i want to do. I can use "OR" logic in "if" statement like if ["YES"] || [ "yes"] but do not want to use OR , Is there any way it can be done?
# 2  
Old 10-06-2010
hi,
try this.

Code:
echo "Enter Yes or No: "
read a

while true
do
 case $a in
	[Yy]* ) 
 	echo "yes is entered"
 	break;;
	[Nn]* ) 
	echo "no is entered"
 	break;;
 	* ) echo "Please enter Yes or No ";;
 esac
done

# 3  
Old 10-06-2010
You can use typset to force uppercase (or lowercase):

Code:
#typeset -u var
#var=yes
#echo $var
YES

This User Gave Thanks to Klashxx For This Post:
ajincoep
# 4  
Old 10-06-2010
Quote:
Originally Posted by ajincoep
user can enter Yes or yes or YES and its captured in variable say var... I can use "OR" logic in "if" statement like if ["YES"] || [ "yes"] but do not want to use OR , Is there any way it can be done?
Here's an idea - you could convert user input to lower case and then compare it with "yes". Ditto with "no".

Code:
$
$ x="Yes"
$
$ echo $x | tr [A-Z] [a-z]
yes
$
$
$ x="YeS"
$
$ echo $x | tr [A-Z] [a-z]
yes
$
$
$ x="YES"
$
$ echo $x | tr [A-Z] [a-z]
yes
$
$

tyler_durden
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