char

DDL info: CHAR(n)

C++ info: UdxBase::UDX_FIXED

struct StringArg
{
  char* data;
  int length;     // Bytes used by string data (not characters).
  int dec_length; // Character declared length ie NCHAR(20) = 20. Will
                  // also be set  if VARCHAR or NVARCHAR.
};

struct StringReturn
{
  char* data;
  int size;
  // On enter it is the size (in bytes) allocated for string data.
  // On return it is the size (in bytes) actually used.
};

The char type often has implicit spaces at the end when passed as an argument. The difference between the specified length and the dec_length indicates how many trailing spaces must be accounted for. Length is in bytes and dec_length is in characters.