Testing files - Ruby example

Input and Output in Ruby example from a Well House Consultants training course
More on Input and Output in Ruby [link]

This example is described in the following article(s):
• Opening and reading files - the ruby fundamentals - [link]

Source code: d3_2 Module: R106

sourcefile = "ac_20090714"

# Test file to see if it exists prior to opening.
# Note use of exists? and size static methods in the file class

if File.exists? sourcefile
        print "File to analyse is #{File.size sourcefile} bytes\n"
        source = File.new sourcefile
else
        STDERR.puts "No file #{sourcefile}"
        exit
end

yesterday = File.new "yestergoogle.txt","w"

all = 0
googlebot = 0
images = 0
source.readlines.each do |access|
        all += 1
        if /^66.249/.match access
                yesterday.write access
                if /Googlebot-Image/.match access
                        STDOUT.write access
                        images += 1
                        end
                googlebot += 1
                end
        end

yesterday.close
source.close

print "Google called up #{googlebot} out of #{all} accesses\n"
print "Of those, #{images} were Google Images\n"

__END__

WomanWithCat:r106 grahamellis$ ruby d3_2
No file ac_20090714
WomanWithCat:r106 grahamellis$

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* Ruby Programming
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