srm

Securely delete file

$ srm [file.txt]

$ srm -r [directory/]

$ srm -s [file.txt]

$ srm -m [file.txt]

$ srm -z [file.txt]

$ srm -v [file.txt]

$ srm -f [file.txt]

srm [-r] [-s|-m|-z] [-f] [-v] files

srm (secure rm) deletes files by overwriting their contents before unlinking, making data recovery significantly more difficult than with standard rm. It offers multiple security levels: simple mode (-s) performs a single overwrite pass for speed, medium mode (-m) uses 7 passes based on the DoD 5220.22-M standard, and the default Gutmann mode (-z) performs 38 passes with various patterns designed to defeat magnetic force microscopy.
The tool handles recursive directory deletion with -r and supports force mode (-f) to skip confirmation prompts. File names are also overwritten before deletion to prevent recovery of filenames from directory entries.

-r, -R

Recursive delete.

Simple overwrite.

Medium (7 passes).

Gutmann (38 passes).

Force, no prompt.

Verbose.

Reduce security for speed.

One filesystem only.

SSD trim may bypass overwrite. Journaling filesystems may retain copies. Slow for large files.

srm was developed for secure file deletion. It implements various overwrite methods to prevent data recovery.

shred(1), rm(1), wipe(1)