Shell Programming and Scripting

awk '
      {
  	$0 = $0 ","                           
  	while($0)                             
  		{
    		  match($0, / *"[^"]*" *,|[^,]*,/)    
    		  temp = substr($0, RSTART, RLENGTH) 
    		  gsub(/^ *?|? *,$/, "", temp)  
    		  gsub(/,/," ",temp)
		  gsub(/([, ])$/,x,temp)
    		  s = s ? s "," temp : temp
    		  $0 = substr($0, RLENGTH + 1)  
  		}
		  $0 = s
		  s  = ""
      }1
    ' file

column 1,column 2,column 3,column 4,column 5,column 6,column 7,column 8,column 9,column 10
12310,42324564756,"a simple string with a   comma","string with or  without commas",string 1,USD,12,70%,08/01/2013,
23455,12312255564,"string  with  multiple  commas","string with or  without commas",string 2,USD,433,70%,07/15/2013,
23525,74535243123,"string   with commas  and - hypens and: semicolans","string with or  without commas",string 1,CAND,744,70%,05/06/2013,
46476,15467534544,"lengthy string  with commas  multiple: colans","string with or  without commas",string 2,CAND,388,70%,09/21/2013,

{
  num_fields = csv_parse($0, csv, ",", "\"", "\"", "\n", 1)
  for(i=1; i<=num_fields; i++) gsub(/,/," ",csv[i])
  print csv_create(csv, num_fields)
}

$ awk -f remove_commas.awk infile3
column 1,column 2,column 3,column 4,column 5,column 6,column 7,column 8,column 9,column 10
12310,42324564756,a simple string with a   comma,string with or  without commas,string 1,USD,12,70%,08/01/2013,
23455,12312255564,string  with  multiple  commas,string with or  without commas,string 2,USD,433,70%,07/15/2013,
23525,74535243123,string   with commas  and - hypens and: semicolans,string with or  without commas,string 1,CAND,744,70%,05/06/2013,
46476,15467534544,lengthy string  with commas  multiple: colans,string with or  without commas,string 2,CAND,388,70%,09/21/2013,