Comparing strings in shell script not working as expected

Question

echo "please enter 2 word"
read var1 var2
if [ "$var 1" = "$var2" ]; then
    echo "These string are the same"
else
    echo "the strings are different"
fi;

The if statement is coming out as false and it's printing the else echo. I looked on various sites and they say this is the format it should be. Am I making some syntax errors?

Solution

 if [ "$var1" = "$var2" ]; then

(No space between $var and 1 in the condition.)

No, always use quote your variables so use: if [ "$var1" = "$var2" ]; then see my answer below on how to use read. — anubhava
– anubhava, Commented Oct 26, 2014 at 17:43
See How to debug a bash script for some information on debugging scripts — the output would have shown you some of your problems (" 1" clearly would be different from one of the words you typed, for example). — Jonathan Leffler
– Jonathan Leffler, Commented Oct 26, 2014 at 19:56

anubhava · Accepted Answer · 2014-10-26 17:34:48Z

2

Problem is this line:

if [ "$var 1" = "$var2" ]; then
          ^---< extra space here <---

Replace this line with:

if [ "$var1" = "$var2" ]; then

EDIT:: To make sure you read both values in two separate variable use IFS like this:

IFS=' ' && read var1 var2

edited Oct 26, 2014 at 17:34

answered Oct 26, 2014 at 17:20

anubhava

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4 Comments

anubhava Over a year ago

That depends on what values you're entering after read. If you enter abc abc then if block will print These string are the same

ROMANIA_engineer Over a year ago

Add echo for strings + for their length after the read line and be sure that your strings are the same.

anubhava Over a year ago

Print your variables as echo "|var1| |$var2|"

anubhava Over a year ago

Also see my EDIT section.

ROMANIA_engineer · Accepted Answer · 2014-10-26 17:25:07Z

1

echo "please enter 2 word"
read var1 
read var2
if [ "$var1" = "$var2" ]; then
    echo "These string are the same"
else
    echo "the strings are different"
fi;

You have to read variables 1 by 1, not in same line.

edited Oct 26, 2014 at 17:25

ROMANIA_engineer

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answered Oct 26, 2014 at 17:24

Yamraj Pandya

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2 Comments

chepner Over a year ago

This is one option. The other is to simply enter words separated by a space.

bpb101 Over a year ago

i dont think it makes a differences but either way its still saying different

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