NAME
rm — remove
directory entries
SYNOPSIS
rm |
[-iRr] file... |
rm |
-f [-iRr]
[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:
- If the file does not exist:
- If the
-foption is not specified,rmshall write a diagnostic message to standard error. - Go on to any remaining files.
- If the
- If file is of type directory, the following steps shall
be taken:
- If neither the
-Roption nor the-roption is specified,rmshall write a diagnostic message to standard error, do nothing more with file, and go on to any remaining files. - If file is an empty directory,
rmmay skip to step 2d. If the-foption is not specified, and either the permissions of file do not permit writing and the standard input is a terminal or the-ioption is specified,rmshall write a prompt to standard error and read a line from the standard input. If the response is not affirmative,rmshall do nothing more with the current file and go on to any remaining files. - 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
rmutility shall not traverse directories by following symbolic links into other parts of the hierarchy, but shall remove the links themselves. - If the
-ioption is specified,rmshall write a prompt to standard error and read a line from the standard input. If the response is not affirmative,rmshall do nothing more with the current file, and go on to any remaining files.
- If neither the
- If file is not of type directory, the
-foption is not specified, and either the permissions of file do not permit writing and the standard input is a terminal or the-ioption is specified,rmshall write a prompt to the standard error and read a line from the standard input. If the response is not affirmative,rmshall do nothing more with the current file and go on to any remaining files. - If the current file is a directory,
rmshall perform actions equivalent to the rmdir(3) function defined in the System Interfaces volume of POSIX.1-2017 called with a pathname of the current file used as the path argument. If the current file is not a directory,rmshall perform actions equivalent to the unlink(3) function defined in the System Interfaces volume of POSIX.1-2017 called with a pathname of the current file used as the path argument.If this fails for any reason,
rmshall 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 XBD
V1_chap12(7) .
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 no file operands, or in the case of
operands that do not exist. Any previous occurrences of the
-ioption shall be ignored. -i- Prompt for confirmation as described previously. Any previous occurrences
of the
-foption 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 XBD 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_MESSAGEScategory. 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_MESSAGEScategory. 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- [
XSI] 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:
CONSEQUENCES OF ERRORS
Default.
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(3) function defined in the System Interfaces
volume of POSIX.1-2017. 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
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.1-2017 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.1-2017 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.1-2017
requires that prompts be done to standard error, for consistency with
cp(1) and mv(1), 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(3) 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.
SEE ALSO
XBD V1_chap08(7), V1_chap12(7)
CHANGE HISTORY
First released in Issue 2.
Issue 5
The FUTURE DIRECTIONS section is added.
Issue 6
Text is added to clarify actions relating to symbolic links as specified in the IEEE P1003.2b draft standard.
Issue 7
Austin Group Interpretations 1003.1-2001 #019 and #091 are applied.
Austin Group Interpretation 1003.1-2001 #126 is applied, changing the description of the LC_MESSAGES environment variable.
POSIX.1-2008, Technical Corrigendum 2, XCU/TC2-2008/0163 [542], XCU/TC2-2008/0164 [819], and XCU/TC2-2008/0165 [542] are applied.