pls help, what's wrong with my shell script...

[koori]

I read PaulLove and JoeMerlino's Book(<<Beginning Unix>>)
and copied this script with vi below(1stscript.sh):

#!/bin/bash
echo "GUESS THE SECRET COLOR"

read COLOR
if [ $COLOR="PURPLE" ]
then
echo "CORRECT!"
else
echo "INCORRECT!! THE SECRET COLOR IS $COLOR"
fi

then i run it and got this result:

$ chmod +x 1stscript.sh
$ ./1stscript.sh
GUESS THE SECRET COLOR
ABC
CORRECT!

WHAT?!!!
....

is there any thing wrong with my script.
my platform is Ubuntu Server 64bit.

pls help, thanx!

[|{urse]

the if statement needs a ; and it's good practice to place your then at the end

#!/bin/bash
echo "GUESS THE SECRET COLOR"
read COLOR
if [ $COLOR="PURPLE" ] ; then
echo "CORRECT!"
else
echo "INCORRECT!! THE SECRET COLOR IS $COLOR"
fi

does that work?

[koori]

doesn't work correctly, it returened the same result...
is there any way to solve this problem?...

[clasificados]

I read PaulLove and JoeMerlino's Book(<<Beginning Unix>>)
and copied this script with vi below(1stscript.sh):

#!/bin/bash
echo "GUESS THE SECRET COLOR"

read COLOR
if [ $COLOR="PURPLE" ]
then
echo "CORRECT!"
else
echo "INCORRECT!! THE SECRET COLOR IS $COLOR"
fi

then i run it and got this result:


WHAT?!!!
....

is there any thing wrong with my script.
my platform is Ubuntu Server 64bit.

pls help, thanx!

what if you define the secret color first



#!/bin/bash
secret=PURPLE
echo "GUESS THE SECRET COLOR"
read COLOR
if [ $COLOR = $secret ] ; then
echo "CORRECT!"
else
echo "INCORRECT!! THE SECRET COLOR IS $secret"
fi

[|{urse]

*facepalm*

I must be getting sleepy lol

[koori]

what if you define the secret color first



#!/bin/bash
secret=PURPLE
echo "GUESS THE SECRET COLOR"
read COLOR
if [ $COLOR = $secret ] ; then
echo "CORRECT!"
else
echo "INCORRECT!! THE SECRET COLOR IS $secret"
fi

nothing has changed...
well, does that mean my shell was broken?

[lavinog]

You just needed to put a space around the =:

#!/bin/bash
echo "GUESS THE SECRET COLOR"

read COLOR
if [ $COLOR = "PURPLE" ]
then
echo "CORRECT!"
else
echo "INCORRECT!! THE SECRET COLOR IS $COLOR"
fi

When doing comparisons, it is a good habit to use quotes around the variable:

if [ "$COLOR" = "PURPLE" ]

Also why say that the secret color is $COLOR when $COLOR is the users response?

GUESS THE SECRET COLOR
asdf
INCORRECT!! THE SECRET COLOR IS asdf

Also, there is a programming section in the forums:
Ubuntu Forums > The Ubuntu Forum Community > Other Community Discussions > Development & Programming > Programming Talk
This would be a good place to get help with this sort of stuff.

[koori]

You just needed to put a space around the =:

#!/bin/bash
echo "GUESS THE SECRET COLOR"

read COLOR
if [ $COLOR = "PURPLE" ]
then
echo "CORRECT!"
else
echo "INCORRECT!! THE SECRET COLOR IS $COLOR"
fi

When doing comparisons, it is a good habit to use quotes around the variable:

if [ "$COLOR" = "PURPLE" ]

Also why say that the secret color is $COLOR when $COLOR is the users response?

GUESS THE SECRET COLOR
asdf
INCORRECT!! THE SECRET COLOR IS asdf

Also, there is a programming section in the forums:
Ubuntu Forums > The Ubuntu Forum Community > Other Community Discussions > Development & Programming > Programming Talk
This would be a good place to get help with this sort of stuff.

Thanx, the problem is solved and thank you for guiding me to the right place
but there is still one strange thing happened.
after i entered "./1stscript.sh" and enter an incorrect value it often return an error message below:

$ ./1stscript.sh
GUESS THE SECRET COLOR
BLUE
./1stscript: line 7:[: =:] unary operator expected
YOUR GUESS WAS WRONG. THE SECRET COLOR IS <PURPLE>.

but if i output this message into file the error message was dissappeared:

$ ./1stscript.sh > error.log
GUESS THE SECRET COLOR
YOUR GUESS WAS WRONG. THE SECRET COLOR IS <PURPLE>.

why...okay maybe i could bring this question into that place.

thank you

[lavinog]

Can you post the contents of the script you used?