I/O Streams

Evo supports various types of I/O streams:

• Console, ConsoleMT
• File
  • FileMT
• Pipe, PipeIn, PipeOut
  • PipeInMT, PipeOutMT
• Socket, SocketCast

Note: Streams use synchronous I/O – see also: Asynchronous I/O

Base class for all stream exceptions: ExceptionStream

Features include:

• Files, pipes, and sockets
• Output formatting (operator<<) – see Stream Formatting
• Text newline conversion (LF, CRLF, CR)
  • Text reading supports all common newline types
  • Text writing converts to system newline type by default – explicit Newline values are not converted
• High performance buffering
  • Read/Write buffers minimize the overhead of low-level I/O calls
  • Output formatting writes directly to stream buffer
• Thread-safe streams with wrappers (ConsoleMT, StreamMT, StreamExtMT) and EVO_IO_MT() macro
• Low-level I/O abstraction layer (OS files, pipes, sockets, etc) for supporting multiple platforms

Streams inherit from Stream (read/write), StreamIn (read-only), or StreamOut (write-only). Note that a Stream (read/write) may be opened in read-only or write-only mode.

Note: Implementation detail classes above are grayed and are not normally instantiated directly

Implementation Detail

A Stream (or StreamIn or StreamOut) type is coupled (via template param) with a type implementing IoDevice (IoFile, IoSocket), which handles the low-level device I/O.

• The stream implementation will use an IoReader to read from the device, and/or an IoWriter to write to the device
• IoReader and IoWriter implement the buffering layer

IoReader, IoWriter, and IoFilterChain use RawBuffer for low-level memory buffers.