First, the length of the SAS character type variable must be able to accommodate the additional characters, otherwise when you concatenate characters to the beginning of a SAS variable, the characters that follow will be truncated (without any warning). A SAS LENGTH statement must appear in your SAS DATA step, and if you have a SAS input file being used, the LENGTH statement must be declared before the SET statement.
You may want to explain exactly what does happen with your attempts, rather than simply stating that it does not work. With this additional information you may find more useful feedback from forum subscribers.
Also, I suggest adding some SAS diagnostic commands such as:
PUT '>diag>' / _ALL_;
And also consider using a SAS format that may help you determine the SAS variable contents, such as $HEXnn. in a PUT statement, as well.
Scott Barry
SBBWorks, Inc.