CSV形式ファイルに列(Column)を追加するAWKスクリプト ref: http://qiita.com/bongkook/items/9748c7114983056f4c88

add_column.awk

#!/bin/gawk -f
#./add_column.awk col=[num] val=[value] quot=[true] [filename] > [new filename]

BEGIN{
    FS=","
}
{
    split($0,cols,",");
    rec = ""
    for (i=0;i<length(cols);i++) {
        colno = (i+1)
        if(colno==col) {
            if(quot=="true") {
                rec = rec ",¥"" val "¥""
            } else {
                rec = rec "," val
            }
        }
        if (i==0) {
            rec = $ + colno
        } else {
            rec = rec "," $ + colno
        }
    }
    print rec
}

new_test.csv

test.csv