Sub-string in a variable length SAP/ABAP

Hi

I have a variable size string with max len sequels to 10. Regarding of the size of the data, it ends with ABC.

I'd like to substring the string before the pattern ABC. How do I achieve this in SAP/ABP. Below is what I was trying which did not work:

samples data source string (myString ): "fafaABC" "lABC" "ruiqiqrABC"

The output I need is : fafa, i , ruiqiqr

Thanks.