title: sed or operator in set of regex
body: <p>The bash script I wrote is supposed to modify my text files. The problem is the speed of operation. There are 4 lines of each file I want to modify. </p>
  
  <p>This is my bash script to modify all .txt files in a given folder:</p>
  
  <pre><code>srcdir="$1" //source directory
  cpr=$2 //given string argument 
  
  find $srcdir -name "*.txt" | while read i; do
      echo "#############################"
      echo "$i"
      echo "Custom string: $cpr"
      echo "#############################"
  
      # remove document name and title
      sed -i 's_document=.*\/[0-9]\{10\}\(, User=team\)\?__g' $i
  
      # remove document date
      sed -i 's|document date , [0-9]\{2\}\/[0-9]\{2\}\/[0-9]\{4\} [0-9]\{2\}:[0-9]\{2\}:[0-9]\{2\} MDT||g' $i
  
      # remove document id
      sed -i 's|document id = 878h67||g' $i
  
      # replace new producer
      sed_arg="-i 's|Reproduced by $cpr|john smith|g' $i"
      eval sed "$sed_arg"
  
  done
  </code></pre>
  
  <p>I dont know how to concatinate all my <code>sed</code> commands in one command or two, so the job would be done faster ( I think! )</p>
  
  <p>I have tried the OR operator for regex <code>|</code> but no success. </p>