base64 -d file.b64 > file
Identify a File’s Type
less file # display the contents of the file (as text) file file # identify the file type via magic bits xxd file | less # view the hex representation strings file # view string found in the file ent file # check the file entropy # values 7.5+ are likely compressed or encrypted
If you need to perform an action on a file in a Linux box as soon as it’s created, use a bash script! An unthrottled while loop is fairly quick and good enough for many scenarios.
In this example, the goal is to move any file that matches
/tmp/moved. There’s nothing special about
the file glob or the
mv command, so replace them with whatever makes sense.
while true do if compgen -G "/tmp/file-*" > /dev/null; then for f in /tmp/file-*; do mv $f /tmp/moved echo "Moved $f" done fi done
compgen is pretty quick even in folders with a large number of files. There’s a good chance it’s not necessary for
folders with only a few files, in which case you can remove the
if statement and just use the
for loop within