rheostream(2rheolef)						    rheolef-6.1 					      rheostream(2rheolef)

NAME

       irheostream, orheostream - large data streams

ABSTRACT

	This class provides a stream interface for large
	data management.
	File decompresion is assumed using
	gzip and a recursive seach in a directory list
	is provided for input.

	    orheostream foo("NAME", "suffix");

	is like

	    ofstream foo("NAME.suffix").

	However, if NAME does not end with `.suffix', then
	`.suffix' is added, and compression
	is done with gzip, adding an additional `.gz' suffix.

	Conversely,

	       irheostream foo("NAME","suffix");

	is like

	       ifstream foo("NAME.suffix").

	However, we look at a search path environment variable
	RHEOPATH in order to find NAME while suffix is assumed.
	Moreover, gzip compressed files, ending
	with the `.gz' suffix is assumed, and decompression is done.

	Finally, a set of useful functions are provided.

DESCRIPTION

	The following code:

	       irheostream is("results", "data");

	will recursively look for a `results[.data[.gz]]' file in the
	directory mentionned by the RHEOPATH environment variable.

	For instance, if you insert in our ".cshrc" something like:

	       setenv RHEOPATH ".:/home/dupont:/usr/local/math/demo"

	the process will study the current directory `.', then, if
	neither `square.data.gz' nor `square.data' exits, it scan
	all subdirectory of the current directory. Then, if file
	is not founded, it start recusively in `/home/dupond'
	and then in `/usr/local/math/demo'.

	File decompression is performed by using
	the gzip command, and data are pipe-lined
	directly in memory.

	If the file start with `.' as `./square' or with a `/'
	as `/home/oscar/square', no search occurs and RHEOPATH
	environment variable is not used.

	Also, if the environment variable RHEOPATH is not set, the
	default value is the current directory `.'.

	For output stream:

	       orheostream os("newresults", "data");

	file compression is assumed, and "newresults.data.gz"
	will be created.

	File loading and storing are mentionned by a message,
	either:

	       ! load "./results.data.gz"

	or:

	       ! file "./newresults.data.gz" created.

	on the clog stream.
	By adding the following:

	       clog << noverbose;

	you turn off these messages
	(see iorheo(4)).

IMPLEMENTATION

       class irheostream : public io::filtering_stream<io::input> {
       public:
	   irheostream() : io::filtering_stream<io::input>() {}
	   irheostream(const std::string& name, const std::string& suffix = std::string());
	   virtual ~irheostream();
	   void open  (const std::string& name, const std::string& suffix = std::string());
	   void close();
       protected:
	   std::ifstream _ifs;
       };
       class orheostream : public io::filtering_stream<io::output> {
       public:
	   orheostream() : io::filtering_stream<io::output>() {}
	   orheostream(const std::string& name, const std::string& suffix = std::string());
	   virtual ~orheostream();
	   void open  (const std::string& name, const std::string& suffix = std::string());
	   void close();
       protected:
	   std::ofstream _ofs;
       };
       std::string itos (std::string::size_type i);
       std::string ftos (const Float& x);

       // catch first occurence of string in file
       bool scatch (std::istream& in, const std::string& ch);

       // has_suffix("toto.suffix", "suffix") -> true
       bool has_suffix (const std::string& name, const std::string& suffix);

       // "toto.suffix" --> "toto"
       std::string delete_suffix (const std::string& name, const std::string& suffix);

       // "/usr/local/dir/toto.suffix" --> "toto.suffix"
       std::string get_basename (const std::string& name);

       // "/usr/local/dir/toto.suffix" --> "/usr/local/dir"
       std::string get_dirname (const std::string& name);

       // "toto" --> "/usr/local/math/data/toto.suffix"
       std::string get_full_name_from_rheo_path (const std::string& rootname, const std::string& suffix);

       // "." + "../geodir" --> ".:../geodir"
       void append_dir_to_rheo_path (const std::string& dir);

       // "../geodir" + "." --> "../geodir:."
       void prepend_dir_to_rheo_path (const std::string& dir);

       bool file_exists (const std::string& filename);

       // string to float
       bool is_float (const std::string&);
       Float to_float (const std::string&);

       // in TMPDIR environment variable or "/tmp" by default
       std::string get_tmpdir();

SEE ALSO

       iorheo(4)

rheolef-6.1							    rheolef-6.1 					      rheostream(2rheolef)