Version 14 (modified by whiteknight, 7 years ago)

Add two idle thoughts about IO to the page

  • Change 'fprintf' to 'PIO_fprintf' where relevant.
  • Plain %s in parrot printf-alike functions do not handle NULL C strings well. Fix.


  • Create an abstract "IOHandle" class
  • Abstract relevant API code from FileHandle and Socket into IOHandle
  • Separate pipe-related logic out of FileHandle
  • Fix StringHandle to be a proper subclass of IOHandle
  • Create a "Select" PMC
  • Use roles and VTABLE_does to differentiate capabilities of different PMC types.


  • Create "StreamDescriptor" PMC type to abstract out system-dependent IO descriptors. Would allow FileHandles and Sockets to be subclassed more easily
  • Create a "StreamBuffer" PMC type to abstract out buffering details. Would allow FileHandles and Sockets to be subclassed more easily, and give all IO types easy access to buffering


  • Change IO API to not use PCCINVOKE calls

Asynchronous IO

various IO related RT tickets


  • Rip out the layers structures and macros. (After the migration is complete.)
  • Remove src/io/io_mmap.c, unused and not useful.
  • Convert I/O layers to I/O objects. (allison)
  • src/io/io_unix.c is the guts of most I/O on most platforms. src/io/io_win32.c is Windows. src/io/io_stdio.c is STDIN, STDOUT, and STDERR. These three need to be ported to the new system. (allison)
  • src/io/io_utf8.c is really the wrong way to go about it. Filehandles should be marked with character set and encoding similar to strings. (allison)
  • Create a PMC named "FileHandle", as a core file handle object, which can be subclassed by various HLLs. (allison)
  • Continue to support different I/O operations on different platforms, using C '#ifdef's on platform-specific sections. (allison)
  • All 'PIO_*' functions change to 'Parrot_io_*'. (Since the implementation is completely changing, better to create new functions with the new names than to change the names of existing functions.) (allison)
  • Remove src/io/io_passdown.c and src/io/io_layers.c, purely implementation artifacts of I/O layers implementation.
  • Change src/io/io_string.c to a subclass of FileHandle PMC, that provides the same interface, but to a string instead of a file handle.