unoconv -f csv *.xls

Failed to connect to /usr/lib/libreoffice/program/soffice.bin (pid=7779) in 6 seconds.
Connector : couldn't connect to socket (Success)
Error: Unable to connect or start own listener. Aborting.

unoconv -f csv filename.xls

$ ls *.xls
ie_data.xls  QTL_Sample_data.xls  WBC_FTTC_Price_List_Entry_16-Aug-10.xls

$ unoconv -f csv *.xls

$ ls *.csv
ie_data.csv  QTL_Sample_data.csv  WBC_FTTC_Price_List_Entry_16-Aug-10.csv