I want to convert all the .odt .doc .xls .pdf files to .txt files.
I want to convert these files to text
Open the file in LibreOffice. Click on "File", "Save-as" scroll down to find the text option. Click that and it will be saved as a text file.
FYI, I had an *.ODT file that was 339.2 KB in size. When I save-as text the size of the file shrunk to ONLY 5.0 KB. Another reason for saving your files as text files.