When you use EVAL fldname for a variable length field, only the data portion of the field is shown. When you use any suffix such as :c or :x for the field, the entire field including the length is shown. To determine the current length of a variable length field, use EVAL fldname:x. The length is the first four hexadecimal digits, in binary format. You must convert this value to decimal form to get the length; for example, if the result is 003DF1F2..., the length is 003D which is (3 * 16) + 13 = 61.