Set A_DB2_ERROR_MAP_FILE to the name of the file that maps database-specific errors to COBOL errors. This variable allows you to map errors using a text file to supplement the default method of providing errors. Create the file using the guidelines described in To create an error map, and then use this variable to indicate the name and location of the file you created.
Example
If the file used for mapping is called db2.err, and this file is located in the directory C:\DB2, you would specify:
A_DB2_ERROR_MAP_FILE c:\DB2\db2.err
There is no default value for this variable.