README.md

This is a fixed-up version of edk2's StdLib/LibC/Uefi/Devices/Console.

NOTE: StdExtLib, StdLibDevConsole, StdLibInteractiveIO and StdLibUefi all go together.

NOTE: the redirection/pipe features rely on using a v2 UEFI Shell.

Differences:

• if StdErr isn't redirected via Shell to a file, redirect it out to ConOut. This solves the unexpected behavior of POSIX apps seemingly printing nothing on error on certain UEFI implementations that always redirect StdErr to serial or to noting.
• Set correct permissions and current time on stdin:/stdout:/stderr:.
• Disallow reading on stdout: and stderr:.
• Make Shell redirection via pipes work (e.g. ls | cat).
• Move Termio init from StdLibUefi.
• Detect Shell redirection of StdIn/StdOut/Stderr (file or 'pipe') to properly apply termios flag. Interactive I/O behavior is only applied if we detect interactive console (e.g. don't want ECHO when redirecting to a file, don't want ICANON if redirecting from a file).
• Strip UTF16 BOM tag from StdIn, which is useful when redirecting via pipe or file.
• Ignore 0-sized writes.
• Catch wide writes where StrLen doesn't match buffer size, to catch Proto->OutputString corruption.
• Remove gMD->StdIo usage (no one cares about it at of 2017 for sure).
• add the notion of "narrow" aliases nstdin:, nstdout: and nstderr:. These only function when dealing with redirection (i.e. never interactive console), and are useful for dealing with binary data. e.g. to make a perfect copy.
• Strip UTF16 BOM tag from narrow StdOut/StdErr.
• st_blksize == 1 to make up for lack of st_blocks (so you can always st_physsize / st_blksize)
• Support v1 Shell mode (e.g. VMware Fusion). Redirection/pipes is a lost cause, but at least the basic use cases work.

Improvements to make:

• VINTR should raise signals.
• whence should not be ignored in da_conSeek.