io >> Input from and output to external formats
File I/O
  append_save
  fexist
Miscellaneous conversion functions
  object2json
  pch2mat
CSV file functions
  csv2cell
  csvconcat
  csvexplode
  cell2csv
XML I/O
  xmlread
  xmlwrite
Spreadsheet I/O user functions for MS-Excel
  oct2xls
  xls2oct
  xlsclose
  xlsfinfo
  xlsopen
  xlsread
  xlswrite
Spreadsheet I/O user functions for OpenOffice.org Calc
  oct2ods
  ods2oct
  odsclose
  odsfinfo
  odsopen
  odsread
  odswrite
Spreadsheet utility functions
  calccelladdress
  chk_spreadsheet_support
  parsecell
Spreadsheet I/O internal functions
  getusedrange
  parse_sp_range
  spsh_chkrange
  spsh_prstype
Spreadsheet function test scripts
  io_xls_testscript
  io_ods_testscript