To permanently delete or remove files on a FreeBSD system, you can use the shred command. The shred command is a utility for overwriting the contents of a file with random data, making it more difficult to recover the deleted file.
To use the shred command, you can run the following command:
shred -u file
Replace file with the name of the file you want to delete. This will overwrite the contents of the file with random data and then delete the file.
By default, shred will overwrite the file 25 times. You can specify a different number of passes using the -n option. For example, to overwrite the file 100 times, you can use the following command:
shred -n 100 -u file
Note that shred does not work on directories. To delete a directory and all of its contents, you can use the rm -rf command. However, this command does not overwrite the contents of the deleted files, so it may be possible to recover deleted data using specialized tools.