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This is one of the ‘gotchas’ that can impact on people when they read files. The underlying commands for loading files in operating systems tend to offer two options:

• Read in text mode

• Read in binary mode

What text mode does is it will translate newline characters to the local operating system convention for newline characters. See IBM, DOS and Windows Newlines to understand why windows expresses newlines with \r\n while the rest of then the Unix based world using uses\n.

Here’s a code fragment which shows the problem on windows:

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title This code fragment shows the problem:
Take a careful look at how in the non binary mode the new line sequences are translated - \r\n to \n.

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title This is the same code fragment with big ugly red boxes around the parts of the annotation to pay attention to
Image Removed Notice how when we read in text mode, the \r\n sequences are translated to \n. But in binary, the data isn’t altered. This can really mess up your files! Image Added

require "FIL.FILreadWrite"

function main(Data)
   FILwrite("~test.txt", "Freddy\r\nSmith\r\n")
   FILread("~test.txt")
   local F = io.open("~test.txt",'r')
   Result = F:read("*a")
   F:close()
   return Result
end