typedef struct PipeRead<Type, Isa> impl SysRead {
  struct pipe* p;
  int i;
  int n;
  __code cbc_piperead1(Type* sys_read, struct pipe* p, __code next(...));
  __code cbc_piperead2(Type* sys_read, int i, int n,struct pipe* p, __code next(...));
  __code cbc_piperead3(Type* sys_read, struct pipe* p, int i, __code next(...));
  __code next(...);
} PipeRead;

/*
 __code cbc_piperead1(Impl* sys_read, struct pipe* p);
 __code cbc_piperead2(Impl* sys_read, int i, int n,struct pipe* p);
 __code cbc_piperead3(Impl* sys_read, struct pipe* p, int i);
*/