You can use the ADIR() function to create an array of files on a certain drive and directory.
SET DEFAULT TO c:\Mydirectory
MyFilesCount = ADIR(MyArray, '*.TXT') &&Get all TXT files at this location
You can then loop thru the above array and search for a file containing a certain string using the ATC() function.
FOR n = 1 TO MyFilesCount
IF ATC("METER", MyArray[n,1] ) > 0 &&First column contains file name
***Run METER process
ENDIF
IF ATC("RADIO", MyArray[n,1] ) > 0 &&First column contains file name
***Run RADIO process
ENDIF
ENDFOR