Think of using file magic to identify data file formats

<typeinfo> provides extended information on intrinsic numeric types

<limits> provides numeric_limits template structs for numeric types. They can be used to study the potential effect of type casts.

Distinguish between internal represenation of samples in intrinsic data types and representation of data in the data file format. For some formats the exact representation can only be deduced for the specific file (like PDAS format or the planned binary format or seife format).

Member datrw::ascii::anonymous_namespace{iasciistream.cc}::explainmodifier (std::ostream &os, const char *const key, const char *const message)

replace with formatmodifiers::ModifierHelp

Member datrw::ascii::anonymous_namespace{iasciistream.cc}::explainmodifierflag (std::ostream &os, const char *const key, const char *const message)

replace with formatmodifiers::ModifierHelp

Member datrw::Edatatype

move this to datatypes.h

Member datrw::su::SUheader::scalelf () const

better handle non-standard values only if appropriate file type modifiers are set; file type modifiers still have to be implemented

Page Notes on library development

Pass header fields through FREE block
the libstdc++ documentation recommends to use stream buffers directly for binary I/O (see also I/O for binary data formats)