Allows you to specify the output file

lib/uplot/command.rb

@@ -25,6 +25,7 @@ module Uplot
       delimiter = parser.delimiter
       transpose = parser.transpose
       headers   = parser.headers
+      pass      = parser.pass
       output    = parser.output
       count     = parser.count
       fmt       = parser.fmt
@@ -41,7 +42,7 @@ module Uplot
         @raw_inputs << input
         @data = Preprocessing.input(input, delimiter, headers, transpose)
         pp @data if @debug
-        case command
+        plot = case command
                when :bar, :barplot
                  Plot.barplot(data, params, @count)
                when :count, :c
@@ -60,9 +61,23 @@ module Uplot
                  Plot.boxplot(data, params)
                else
                  raise "unrecognized plot_type: #{command}"
-        end.render($stderr)
+               end
 
-        print input if output
+        if output.is_a?(IO)
+          plot.render(output)
+        else
+          File.open(output, 'w') do |f|
+            plot.render(f)
+          end
+        end
+
+        if pass.is_a?(IO)
+          print input
+        elsif pass
+          File.open(pass, 'w') do |f|
+            f.print(input)
+          end
+        end
       end
     end
   end

lib/uplot/command/parser.rb

@@ -7,7 +7,7 @@ module Uplot
   class Command
     class Parser
       attr_reader :command, :params,
-                  :delimiter, :transpose, :headers, :output, :count, :fmt, :debug
+                  :delimiter, :transpose, :headers, :pass, :output, :count, :fmt, :debug
 
       def initialize
         @command = nil
@@ -16,7 +16,8 @@ module Uplot
         @delimiter  = "\t"
         @transpose  = false
         @headers    = nil
-        @output     = false
+        @pass       = false
+        @output     = $stderr
         @count      = false
         @fmt        = 'xyy'
         @debug      = false
@@ -26,7 +27,10 @@ module Uplot
         OptionParser.new do |opt|
           opt.program_name = 'uplot'
           opt.version = Uplot::VERSION
-          opt.on('-O', 'outputs the standard input data to the standard output', TrueClass) do |v|
+          opt.on('-O', '--pass [VAL]', 'file to output standard input data to [stdout]') do |v|
+            @pass = v || $stdout
+          end
+          opt.on('-o', '--output VAL', 'file to output results to [stderr]') do |v|
             @output = v
           end
           opt.on('-d', '--delimiter VAL', 'use DELIM instead of TAB for field delimiter', String) do |v|