How do I permanently delete files in Linux to prevent data recovery?

If you want to specify how many times to overwrite the file, you can use the -n option. For example, shred -n 10 example.txt overwrites the file 10 times.

To overwrite and delete a file in one step, use the -u option. For example,

shred -u example.txt

It will overwrite the file and then delete it.

You can also use the -z option to hide the shredding by overwriting the file with zeros at the end. For example,

shred -z example.txt

It will overwrite the file and then hide the shredding process.

If you need to overwrite only a specific portion of a file, you can use the -s option followed by the number of bytes. For example,

shred -s 10 example.txt

It will overwrite the first 10 bytes of the file.