File.write doesn't write exactly what I want

Question

I have a very very simple example:

content = [0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x0D, 0x0A] # "Hello\r\n"
f = File.new("PATH", "w")
content.each {|b| f.write(b.chr)}
f.close

I tried to write something to files and then I discovered, that Ruby writes for each \r a \r and for each \n a \r\n. So when I run my code example, Ruby doesn't write Hello\r\n into the file, it writes Hello\r\r\n. Is there a way to prevent this or to write each byte without adding other bytes?

Answer 1

The reason mentioned in the documentation IO Open Mode

"b" - Binary file mode. Suppresses EOL <-> CRLF conversion on Windows and sets external encoding to ASCII-8BIT unless explicitly specified.

Thus you need to use 'wb' instead of 'w' to resolve your issue.

You can write code something like below :

content = [0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x0D, 0x0A] # "Hello\r\n"
f = File.new("PATH", "wb")
content.each {|b| f.write(b.chr)}
f.close