Getting the EXIF file type using the command line in case you have a huge amount of *.REN Files or you just don’t know why a file can’t be viewed with default applications.
Output TXT file ist TAB delimited. Eays to open in LibreOffice calc or Microsoft Excel
Requirements: almost any Linux dist and exiftool installed
apt-get install libimage-exiftool-perl
find . -name '*.pdf*' -exec exiftool -T -filename -filetype {} > results.txt \;