rm(1) - NetBSD Manual Pages

RM(1)                   NetBSD General Commands Manual                   RM(1)


NAME

     rm -- remove directory entries


SYNOPSIS

     rm [-f | -i] [-dPRrvWx] file ...


DESCRIPTION

     The rm utility attempts to remove the non-directory type files specified
     on the command line.  If the permissions of the file do not permit writ-
     ing, and the standard input device is a terminal, the user is prompted
     (on the standard error output) for confirmation.

     The options are as follows:

     -d    Attempt to remove directories as well as other types of files.

     -f    Attempt to remove the files without prompting for confirmation,
           regardless of the file's permissions.  If the file does not exist,
           do not display a diagnostic message or modify the exit status to
           reflect an error.  The -f option overrides any previous -i options.

     -i    Request confirmation before attempting to remove each file, regard-
           less of the file's permissions, or whether or not the standard
           input device is a terminal.  The -i option overrides any previous
           -f options.

     -P    Overwrite regular files before deleting them.  Files are overwrit-
           ten three times, first with the byte pattern 0xff, then 0x00, and
           then with random data, before they are deleted.  Some care is taken
           to ensure that the data are actually written to disk, but this can-
           not be guaranteed, even on traditional filesystems; on log-struc-
           tured filesystems or if any block-journaling scheme is in use, this
           option is completely useless.  If the file cannot be overwritten,
           it will not be removed.

     -R    Attempt to remove the file hierarchy rooted in each file argument.
           The -R option implies the -d option.  If the -i option is speci-
           fied, the user is prompted for confirmation before each directory's
           contents are processed (as well as before the attempt is made to
           remove the directory).  If the user does not respond affirmatively,
           the file hierarchy rooted in that directory is skipped.

     -r    Equivalent to -R.

     -v    Cause rm to be verbose, showing files as they are processed.

     -W    Attempts to undelete the named files.  Currently, this option can
           only be used to recover files covered by whiteouts.

     -x    When removing a hierarchy, do not cross mount points.

     The rm utility removes symbolic links, not the files referenced by the
     links.

     It is an error to attempt to remove the files ``.'' and ``..''.


EXIT STATUS

     The rm utility exits 0 if all of the named files or file hierarchies were
     removed, or if the -f option was specified and all of the existing files
     or file hierarchies were removed.  If an error occurs, rm exits with a
     value >0.


EXAMPLES

     rm uses getopt(3) standard argument processing.  Removing filenames that
     begin with a dash (e.g., -file) in the current directory which might oth-
     erwise be taken as option flags to rm can be accomplished as follows:

     rm -- -file

     or

     rm ./-file


COMPATIBILITY

     The rm utility differs from historical implementations in that the -f
     option only masks attempts to remove non-existent files instead of mask-
     ing a large variety of errors.

     Also, historical BSD implementations prompted on the standard output, not
     the standard error output.


SEE ALSO

     rmdir(1), undelete(2), unlink(2), fts(3), getopt(3), symlink(7)


STANDARDS

     The rm utility is expected to be IEEE Std 1003.2 (``POSIX.2'') compati-
     ble.  The -v and -x options are extensions.

     The -P option attempts to conform to U.S. DoD 5220-22.M, "National Indus-
     trial Security Program Operating Manual" ("NISPOM") as updated by Change
     2 and the July 23, 2003 "Clearing & Sanitization Matrix".  However,
     unlike earlier revisions of NISPOM, the 2003 matrix imposes requirements
     which make it clear that the standard does not and can not apply to the
     erasure of individual files, in particular requirements relating to spare
     sector management for an entire magnetic disk.  Because these
     requirements are not met, the -P option does not conform to the standard.


HISTORY

     An rm utility appeared in Version 1 AT&T UNIX.


BUGS

     The -P option assumes that the underlying file system is a fixed-block
     file system.  FFS is a fixed-block file system, LFS is not.  In addition,
     only regular files are overwritten, other types of files are not.  Recent
     research indicates that as many as 35 overwrite passes with carefully
     chosen data patterns may be necessary to actually prevent recovery of
     data from a magnetic disk.  Thus the -P option is likely both insuffi-
     cient for its design purpose and far too costly for default operation.
     However, it will at least prevent the recovery of data from FFS volumes
     with fsdb(8).

NetBSD 9.1                      August 12, 2016                     NetBSD 9.1