Split a csv including header into x discrete CSVs

splitcsv.sh

# replace 'FILE.csv' w/ desired split file
# set 'split -l n' as number of rows per new file

tail -n +2 FILE.csv | split -l 100000 - split_
for file in split_*
do
    head -n 1 FILE.csv > tmp_file
    cat $file >> tmp_file
    mv -f tmp_file $file
done

# via Martin Dinov: http://stackoverflow.com/a/20721203/1676407