Retrieves the offset of a member from the beginning of its parent structure.
size_t offsetof( structName, memberName );
Name of the parent data structure.
Name of the member in the parent data structure for which to determine the offset.
offsetof returns the offset in bytes of the specified member from the beginning of its parent data structure. It's undefined for bit fields.
offsetof macro returns the offset in bytes of
memberName from the beginning of the structure specified by
structName as a value of type
size_t. You can specify types with the
offsetof is not a function and cannot be described using a C prototype.
For more compatibility information, see Compatibility.
All versions of the C run-time libraries.