diststream(2rheolef)

✨ diststream ✨

okay bestie, this is the rheolef-7.2 page for diststream, and it's literally the glow-up your i/o needed 💅

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🌸 NAME 🌸

diststream — i/o streams in a distributed environment (rheolef-7.2) 🦋

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💖 DESCRIPTION 💖

so the idiststream and odiststream classes give you a stream input and output interface for parallel and distributed codes. The main difference? Let's talk about it, because it's giving main character energy ✨

Recall that, with the usual std::istream and std::ostream, any i/o operation is executed on all processes: e.g. the output is printed many times. Not cute. In contrast, idiststream and odiststream manage the distributed environment nicely 🫶

For small data — like int, double or string — a specific processor is selected for i/o operations. For large data, the i/o operations are delegated to a specific class member function, when available. Periodt. 👑

And for convenience? The standard streams cin, cout, clog and cerr are extended as din, dout, dlog and derr, respectively. Obsessed with this fr fr 🌈

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🎀 FILE SUFFIXES 🎀

okay so, finally: an optional suffix extension to the file name is automatically handled 💫

odiststream foo('NAME', 'suffix');

is similar to

ofstream foo('NAME.suffix');

Conversely,

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

is similar to

ifstream foo('NAME.suffix');

see how that works? iconic. 💅

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🦋 FILE SEARCH 🦋

Recursive search in a directory list is provided for finding the input file 🔍 However, we look at a search path environment variable RHEOPATH in order to find NAME while the suffix is assumed. And moreover? gzip compressed files, ending with the .gz suffix, are handled — and decompression is done automatically on the fly in that case. no cap. 🧚

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💜 COMPRESSION 💜

File compression/decompresion is handled on the fly, thanks to the gzip library. The data compression is assumed by default for output: it can be deactivated while opening a file by an optional argument:

odiststream foo('NAME', 'suffix', io::nogz);

lowkey the vibes here are immaculate 🍓

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🌟 APPEND MODE 🌟

An existing file, possibly compressed, can be reopen in append mode. New results will be appended at the end of an existing file:

odiststream foo('NAME', 'suffix', io::app);

so you keep the old stuff and stack the new stuff on top, bestie ✨

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🫶 FLUSH 🫶

The flush member function is nicely handled in compression mode: this feature allows intermediate results to be available during long computations. Buffers are flushed and data are available in the output file. literally perfect for those long-running jobs 😭🔥

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👑 IMPLEMENTATION 👑

This documentation has been generated from file linalg/lib/diststream.h 📄

class idiststream {
public:
  typedef std::size_t size_type;

// allocators/deallocators:

  idiststream();
  idiststream (std::istream& is, const communicator& comm = communicator());
  idiststream (std::string filename, std::string suffix = "",
             const communicator& comm = communicator());
  ~idiststream();

// modifiers:

  void open (std::string filename, std::string suffix = "",
             const communicator& comm = communicator());
  void close();

// accessors:

  const communicator& comm() const { return _comm; }
  bool good() const;
  operator bool() const { return good(); }
  static size_type io_proc();

};

class odiststream {
public:
  typedef std::size_t size_type;

// allocators/deallocators:

  odiststream();
  odiststream (std::string filename, std::string suffix = "",
              io::mode_type mode = io::out, const communicator& comm = communicator());
  odiststream (std::string filename,
              io::mode_type mode, const communicator& comm = communicator());
  odiststream (std::string filename, std::string suffix, const communicator& comm);
  odiststream (std::string filename, const communicator& comm);
  odiststream(std::ostream& os, const communicator& comm = communicator());
  ~odiststream();

// modifiers:

   void open (std::string filename, std::string suffix = "",
             io::mode_type mode = io::out, const communicator& comm = communicator());
   void open (std::string filename,
             io::mode_type mode, const communicator& comm = communicator());
   void open (std::string filename, std::string suffix,
             const communicator& comm);
   void open (std::string filename, const communicator& comm);
   void flush();
   void close();

// accessors:

   const communicator& comm() const { return _comm; }
   bool good() const;
   operator bool() const { return good(); }
   static size_type io_proc();

};

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🌈 AUTHOR 🌈

Pierre Saramito <Pierre.Saramito@imag.fr> 💌

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⭐ COPYRIGHT ⭐

Copyright (C) 2000-2018 Pierre Saramito <Pierre.Saramito@imag.fr> GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. 🙈

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aaaand that's the whole page bestie 🎀 this was rheolef Version 7.2, and the page is diststream(2rheolef). go forth and stream, you got this 💖✨🦋