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PROGRAM:

NAME

rm — remove directory entries

SYNOPSIS

rm [−fiRr] file...

DESCRIPTION

The rm utility shall remove the directory entry specified by each file argument.

If either of the files dot or dot-dot are specified as the basename portion of an operand
(that is, the final pathname component) or if an operand resolves to the root directory,
rm shall write a diagnostic message to standard error and do nothing more with such
operands.

For each file the following steps shall be taken:

1. If the file does not exist:

a. If the −f option is not specified, rm shall write a diagnostic message to standard
error.

b. Go on to any remaining files.

2. If file is of type directory, the following steps shall be taken:

a. If neither the −R option nor the −r option is specified, rm shall write a
diagnostic message to standard error, do nothing more with file, and go on to any
remaining files.

b. If the −f option is not specified, and either the permissions of file do not
permit writing and the standard input is a terminal or the −i option is specified,
rm shall write a prompt to standard error and read a line from the standard input.
If the response is not affirmative, rm shall do nothing more with the current file
and go on to any remaining files.

c. For each entry contained in file, other than dot or dot-dot, the four steps listed
here (1 to 4) shall be taken with the entry as if it were a file operand. The rm
utility shall not traverse directories by following symbolic links into other
parts of the hierarchy, but shall remove the links themselves.

d. If the −i option is specified, rm shall write a prompt to standard error and read
a line from the standard input. If the response is not affirmative, rm shall do
nothing more with the current file, and go on to any remaining files.

3. If file is not of type directory, the −f option is not specified, and either the
permissions of file do not permit writing and the standard input is a terminal or the
−i option is specified, rm shall write a prompt to the standard error and read a line
from the standard input. If the response is not affirmative, rm shall do nothing more
with the current file and go on to any remaining files.

4. If the current file is a directory, rm shall perform actions equivalent to the rmdir()
function defined in the System Interfaces volume of POSIX.1‐2008 called with a
pathname of the current file used as the path argument. If the current file is not a
directory, rm shall perform actions equivalent to the unlink() function defined in the
System Interfaces volume of POSIX.1‐2008 called with a pathname of the current file
used as the path argument.

If this fails for any reason, rm shall write a diagnostic message to standard error,
do nothing more with the current file, and go on to any remaining files.

The rm utility shall be able to descend to arbitrary depths in a file hierarchy, and shall
not fail due to path length limitations (unless an operand specified by the user exceeds
system limitations).

OPTIONS

The rm utility shall conform to the Base Definitions volume of POSIX.1‐2008, Section 12.2,
Utility Syntax Guidelines.

The following options shall be supported:

−f Do not prompt for confirmation. Do not write diagnostic messages or modify the
exit status in the case of nonexistent operands. Any previous occurrences of the
−i option shall be ignored.

−i Prompt for confirmation as described previously. Any previous occurrences of the
−f option shall be ignored.

−R Remove file hierarchies. See the DESCRIPTION.

−r Equivalent to −R.

OPERANDS

The following operand shall be supported:

file A pathname of a directory entry to be removed.

STDIN

The standard input shall be used to read an input line in response to each prompt
specified in the STDOUT section. Otherwise, the standard input shall not be used.

INPUT FILES

None.

ENVIRONMENT VARIABLES

The following environment variables shall affect the execution of rm:

LANG Provide a default value for the internationalization variables that are unset or
null. (See the Base Definitions volume of POSIX.1‐2008, Section 8.2,
Internationalization Variables for the precedence of internationalization
variables used to determine the values of locale categories.)

LC_ALL If set to a non-empty string value, override the values of all the other
internationalization variables.

LC_COLLATE
Determine the locale for the behavior of ranges, equivalence classes, and multi-
character collating elements used in the extended regular expression defined for
the yesexpr locale keyword in the LC_MESSAGES category.

LC_CTYPE Determine the locale for the interpretation of sequences of bytes of text data
as characters (for example, single-byte as opposed to multi-byte characters in
arguments) and the behavior of character classes within regular expressions used
in the extended regular expression defined for the yesexpr locale keyword in the
LC_MESSAGES category.

LC_MESSAGES
Determine the locale used to process affirmative responses, and the locale used
to affect the format and contents of diagnostic messages and prompts written to
standard error.

NLSPATH Determine the location of message catalogs for the processing of LC_MESSAGES.

ASYNCHRONOUS EVENTS

Default.

STDOUT

Not used.

STDERR

Prompts shall be written to standard error under the conditions specified in the
DESCRIPTION and OPTIONS sections. The prompts shall contain the file pathname, but their
format is otherwise unspecified. The standard error also shall be used for diagnostic
messages.

OUTPUT FILES

None.

EXTENDED DESCRIPTION

None.

EXIT STATUS

The following exit values shall be returned:

0 Each directory entry was successfully removed, unless its removal was canceled by a
non-affirmative response to a prompt for confirmation.

>0 An error occurred.

CONSEQUENCES OF ERRORS

Default.

The following sections are informative.

APPLICATION USAGE

The rm utility is forbidden to remove the names dot and dot-dot in order to avoid the
consequences of inadvertently doing something like:

rm −r .*

Some implementations do not permit the removal of the last link to an executable binary
file that is being executed; see the [EBUSY] error in the unlink() function defined in the
System Interfaces volume of POSIX.1‐2008. Thus, the rm utility can fail to remove such
files.

The −i option causes rm to prompt and read the standard input even if the standard input
is not a terminal, but in the absence of −i the mode prompting is not done when the
standard input is not a terminal.

EXAMPLES

1. The following command:

rm a.out core

removes the directory entries: a.out and core.

2. The following command:

rm −Rf junk

removes the directory junk and all its contents, without prompting.

RATIONALE

For absolute clarity, paragraphs (2b) and (3) in the DESCRIPTION of rm describing the
behavior when prompting for confirmation, should be interpreted in the following manner:

if ((NOT f_option) AND
((not_writable AND input_is_terminal) OR i_option))

The exact format of the interactive prompts is unspecified. Only the general nature of the
contents of prompts are specified because implementations may desire more descriptive
prompts than those used on historical implementations. Therefore, an application not using
the −f option, or using the −i option, relies on the system to provide the most suitable
dialog directly with the user, based on the behavior specified.

The −r option is historical practice on all known systems. The synonym −R option is
provided for consistency with the other utilities in this volume of POSIX.1‐2008 that
provide options requesting recursive descent through the file hierarchy.

The behavior of the −f option in historical versions of rm is inconsistent. In general,
along with ``forcing'' the unlink without prompting for permission, it always causes
diagnostic messages to be suppressed and the exit status to be unmodified for nonexistent
operands and files that cannot be unlinked. In some versions, however, the −f option
suppresses usage messages and system errors as well. Suppressing such messages is not a
service to either shell scripts or users.

It is less clear that error messages regarding files that cannot be unlinked (removed)
should be suppressed. Although this is historical practice, this volume of POSIX.1‐2008
does not permit the −f option to suppress such messages.

When given the −r and −i options, historical versions of rm prompt the user twice for each
directory, once before removing its contents and once before actually attempting to delete
the directory entry that names it. This allows the user to ``prune'' the file hierarchy
walk. Historical versions of rm were inconsistent in that some did not do the former
prompt for directories named on the command line and others had obscure prompting behavior
when the −i option was specified and the permissions of the file did not permit writing.
The POSIX Shell and Utilities rm differs little from historic practice, but does require
that prompts be consistent. Historical versions of rm were also inconsistent in that
prompts were done to both standard output and standard error. This volume of POSIX.1‐2008
requires that prompts be done to standard error, for consistency with cp and mv, and to
allow historical extensions to rm that provide an option to list deleted files on standard
output.

The rm utility is required to descend to arbitrary depths so that any file hierarchy may
be deleted. This means, for example, that the rm utility cannot run out of file
descriptors during its descent (that is, if the number of file descriptors is limited, rm
cannot be implemented in the historical fashion where one file descriptor is used per
directory level). Also, rm is not permitted to fail because of path length restrictions,
unless an operand specified by the user is longer than {PATH_MAX}.

The rm utility removes symbolic links themselves, not the files they refer to, as a
consequence of the dependence on the unlink() functionality, per the DESCRIPTION. When
removing hierarchies with −r or −R, the prohibition on following symbolic links has to be
made explicit.

FUTURE DIRECTIONS

None.

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