Input/Output

File Stream

Read/Write from/to an opened stream.

To read a file we can use open with the correct modifier and then read its contents with a proper method:

• r : read only stream

• r+ : read and write stream

If open is followed by a block, the file object is passed to the block and the stream is automatically closed at block termination. Inside the block, you have a file object, and you can use different methods as read, each, readline and gets among more. Thee methods can be used with many optional arguments in order to perform position dependent and length dependent reading.

Read

File.open("multi_line.txt", "r") do |file|
    contents = file.read
    puts contents
end

# read can be also used without opening the file
content = File.read("multi_line.txt")

# readline is similar to read but it can be used to obtain an array 
# containing the lines of the file:
File.readlines("multi_line.txt")

# each can also be used to read a file line by line
file = File.new("multi_line.txt", "r")

count = 0
file.each do |line|
   puts "n:#{count} #{line}"
   counts+=1
end

Write

Working with Nmap files