What does the% operator do for strings in InstallScript?

Question

I am looking through InstallScript code.

With integers, I use the% operator modulo. I am not familiar with it in the lines.

if (szSomeString % szSomeOtherString) then // do something endif; 

What is this reduction?

I understand that this should be simple for Google, but I have not found any luck yet.

Answer 1

In the InstallScript Reference Guide :

 Find String Operator (%) Locates a substring in another string