krb5_encode_test runs through all the functions declared in

 src/include/krb5/asn.1/krb5_encode.h.  It passes various sample

 inputs to each function and prints the result to standard

 output.  This output should match the contents of the file

 "reference_encode.out".

 Each function is first run with a relatively simple, contrived

 sample structure.  Then if the structure has any optional parts,

 these parts are cleared and another run is made.

 Some structures (namely, those containing a krb5_kdc_req_body)

 have a third run, due to the fact that two of the kdc_req_body's

 optional fields have mutually exclusive conditions under which

 they may be omitted.

krb5_decode_test runs through all the functions declared in

 src/include/krb5/asn.1/krb5_decode.h.  It has the encodings in

 reference_encode.out hard-coded into itself.  It sets up the

 krb5 structures the same way krb5_encode_test does, then passes

 its hard-coded encoding strings through the krb5 decoders.

 The outputs of these functions are compared to the previously

 set-up structures in memory, and the results are reported to

 standard output.  If every line comes out prefixed by "OK: ",

 then the decoders are working properly.  If any decoder produces

 an anomalous output, then its output line will be prefixed by

 "ERROR: "