Convert excel spreadsheet to csv on linux (xlsx to csv)
Get gnumeric
apt-get install gnumeric
Then use ssconvert to do the conversion
ssconvert oldfile.xlsx newfile.csv
On a headless server (such as a droplet) it may issue a lot of warnings. Pipe output and warning to null via:
ssconvert oldfile.xlsx newfile.csv > /dev/null 2>&1
Well this is a nifty trick!