if ( a == 5 && b == 6 ) like expressions
 

Hi all,

I somehow couldn't find the "linux bash script" equivalent of this C expression. How do we bind several comparisons together in bash script?

Best,
Bekir

The 'test' command is used in bash for this. You can do 'man test' to see its syntax. The '[' command is equivalent to test:

if [ $a = 5 -a $b = 6 ]; then
echo "condition true"
else
echo "condition false"
fi

Thanks Udi, I know it is such a simple question..
But I still couldn't get it working with "test", I mean it is not clarified in the manual, how to bind several expressions together. Would you have time to write the example with "test"?

Regards,
Bekir

The same example with test is the same as the previous example:

if test $a = 5 -a $b = 6 ; then
echo "condition true"
else
echo "condition false"
fi


From the manual page:
EXPRESSION1 -a EXPRESSION2
both EXPRESSION1 and EXPRESSION2 are true

-a is AND. The statement is true when $foo is equal 5 and $boo is equal 10.
-o is OR. Statement is true for $foo = 5 or $boo = 10.

That's how I always use it. And it works. Maybe there's some other way to use AND/OR expressions but I don't care. This has worked for me.

Hope I helped.

I got it working..! :)
Both helps are greatly appreciated..
Thanks a lot for your time..

Best,
Bekir

It's the simplest way, I guess.

You can always concatenate two tests, which I use sometimes for the sake of clarity, but it's probably less efficient.