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Read every 8 bytes from a file in Ruby

I am trying to read a file in ruby, but I need to read 8 bytes at a time. Example :.

file = "a1b2c3d4c5d6e7f8g9h0"
file.each_8_bytes do |f|
  puts f
end

Output

=> a1b2c3d4
=> c5d6e7f8
=> g9h0

how do i do it?

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2 answers 


f = File.open(file)
f.read(8) #=> a1b2c3d4
f.read(8) #=> c5d6e7f8
f.read(8) #=> g9h0
...
f.close

Or do it automatically,



File.open(file) do |f|
  while s = f.read(8)
    puts s
  end
end
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If you are putting the results into an array, you probably have enough memory to read the entire file into a string, in which case you can do the following.

text = "My dog has fleas.  Oh, my!"
File.write('temp', text) #=> 26

text = File.read('temp')
((text.size+7)/8).times.map { |i| text.slice(i*8,8) }
  #=> ["My dog h", "as fleas", ".  Oh, m", "y!"]


or, if you like:

((text.size+7)/8).times.map { text.slice!(0,8) }
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