Step by Step solution about How to resolve the algorithm Read a file line by line step by step in the Ruby programming language

Ruby offers a number of different ways to read a file, depending on the circumstances. The simplest and most common way is to use the File.open method, which will return a File object representing the file you want to read. You can then use this object to call the each method, which will yield each line of the file to the block you provide.

File.open("foobar.txt") do |file|
 file.each {|line| puts line}
end

If you need to read a file from a subprocess, you can use the IO.foreach method, which will take a command as an argument and yield each line of the output of that command to the block you provide.

IO.foreach "| grep afs3 /etc/services" do |line|
 puts line
end

One thing to note is that the IO.foreach method will not automatically close the file when it is finished reading it, so you should be sure to do so yourself.

filename = "|strange-name.txt"
File.open(filename) do |file|
 file.each {|line| puts line}
ensure
 file.close
end

IO.foreach "foobar.txt" do |line|
  # Do something with line.
  puts line
end


# File inherits from IO, so File.foreach also works.
File.foreach("foobar.txt") {|line| puts line}


# IO.foreach and File.foreach can also read a subprocess.
IO.foreach "| grep afs3 /etc/services" do |line|
  puts line
end


filename = "|strange-name.txt"
File.open(filename) do |file|
  file.each {|line| puts line}
end