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On 18/02/2014 15.04, Roberto Ierusalimschy wrote:
ANSI C says that about text files:

   Data read in from a text stream will necessarily compare equal to
   the data that were earlier written out to that stream only if: the
   data consist only of printing characters and the control characters
   horizontal tab and new-line; no new-line character is immediately
   preceded by space characters; and the last character is a new-line

So, there is no garanties that a text file with embedded zeros will be
read correctly, no matter how we implement it.

Another example is the "end-of-text" character (0x04 in Unix, 0x1a in Windows) that terminates text files.

Just for the record: In my machine, the following program,

   local count = 0
   for l in io.lines() do
     count = count + #l

reading the Bible, takes ~0.07s with the current implementation and
~0.14s with this proposal.

I really can't see any advantage in making text file reading worse, just to handle the nonstandard case "read a binary file using text file functions". Especially because the nonstandard case can be easily handled in other ways, either in C or in pure Lua.