Shell Programming and Scripting

I have the following code

Code:

VarSalida = "52" 
VarSalidaCtl = "" 

echo "VarSalida: $ VarSalida" 
echo "VarSalidaCtl: $ VarSalidaCtl" 


if [$ VarSalida == $ VarSalidaCtl] 
***** then 
echo "true" 
***** else 
********** echo "false" 
***** fi

the problem is this

Code:

test [8]: VarSalida: 0403-012 A test command parameter is not valid.

is not able to compare with null value and I nesecito so someone can help me

If the problem is really only that... try replacing ==with -eq
== is for string comparison, -eq for arithmetic test

There need to be space around the single brackets ( and also a single = sign ) and no space after the $-sign and best to have quotes around the variables...

Code:

if [ "$VarSalida" = "$VarSalidaCtl" ]

Of course the asterisks need to go as well.

prueba[8]: [$: not found.

---------- Post updated at 05:39 PM ---------- Previous update was at 05:38 PM ----------

Thanks it worked !!!!!!!!

When comparing decimal numeric strings for equality, the results from:

Code:

[ "$n1" = "$n2" ]
       and
[ "$n1" -eq "$n2" ]

will always be identical as long as there aren't any "leading" zeros at the start of the string or after an initial minus sign

But when one of the two numbers can be an empty string (as in the example given by the OP), the first test will indicate that the two strings are not equal; but the second test will give you a syntax error in some shells (such as bash) because an empty string is not a numeric value. Other shells (such as ksh) will compare them as if the empty string is zero when using -eq.

Some shells accept == as a synonym for = as a test operator, but correctly writen applications will use =, not == in this form of test.