The ASN.1 C++ runtime classes are wrapper classes that provide an object-oriented interface to the ASN.1 C runtime library functions. The classes described in this manual are derived from the common classes documented in the ASN1C C/C++ Common runtime manual. They are specific to the Packed Encoding Rules (PER)as defined in the X.691 ITU-T standard. These PER specific C++ runtime classes include the PER message buffer classes.

The ASN.1 PER Runtime Library contains the low-level constants, types, and functions that are assembled by the compiler to encode/decode more complex structures.

This library consists of the following items:

• A global include file ("asn1per.h") that is compiled into all generated source files.
• An object library of functions that are linked with the C functions after compilation with a C complier.

In general, programmers will not need to be too concerned with the details of these functions. The ASN.1 compiler generates calls to them in the C or C++ source files that it creates. However, the functions in the library may also be called on their own in applications requiring their specific functionality.