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<center><font size="2">The Open Group Base Specifications Issue 6<br>
IEEE Std 1003.1-2001<br>
Copyright &copy; 2001 The IEEE and The Open Group, All Rights reserved.</font></center>
<!--header end-->
<hr size="2" noshade>
<h4><a name="tag_04_121_01"></a>NAME</h4>
<blockquote>rm - remove directory entries</blockquote>
<h4><a name="tag_04_121_02"></a>SYNOPSIS</h4>
<blockquote class="synopsis">
<p><code><tt>rm</tt> <b>[</b><tt>-fiRr</tt><b>]</b> <i>file</i><tt>...</tt></code></p>
</blockquote>
<h4><a name="tag_04_121_03"></a>DESCRIPTION</h4>
<blockquote>
<p>The <i>rm</i> utility shall remove the directory entry specified by each <i>file</i> argument.</p>
<p>If either of the files dot or dot-dot are specified as the basename portion of an operand (that is, the final pathname
component), <i>rm</i> shall write a diagnostic message to standard error and do nothing more with such operands.</p>
<p>For each <i>file</i> the following steps shall be taken:</p>
<ol>
<li>
<p>If the <i>file</i> does not exist:</p>
<ol type="a">
<li>
<p>If the <b>-f</b> option is not specified, <i>rm</i> shall write a diagnostic message to standard error.</p>
</li>
<li>
<p>Go on to any remaining <i>files</i>.</p>
</li>
</ol>
</li>
<li>
<p>If <i>file</i> is of type directory, the following steps shall be taken:</p>
<ol type="a">
<li>
<p>If neither the <b>-R</b> option nor the <b>-r</b> option is specified, <i>rm</i> shall write a diagnostic message to standard
error, do nothing more with <i>file</i>, and go on to any remaining files.</p>
</li>
<li>
<p>If the <b>-f</b> option is not specified, and either the permissions of <i>file</i> do not permit writing and the standard input
is a terminal or the <b>-i</b> option is specified, <i>rm</i> shall write a prompt to standard error and read a line from the
standard input. If the response is not affirmative, <i>rm</i> shall do nothing more with the current file and go on to any
remaining files.</p>
</li>
<li>
<p>For each entry contained in <i>file</i>, 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 <i>file</i> operand. The <i>rm</i> utility shall not traverse directories by following symbolic links into
other parts of the hierarchy, but shall remove the links themselves.</p>
</li>
<li>
<p>If the <b>-i</b> option is specified, <i>rm</i> shall write a prompt to standard error and read a line from the standard input.
If the response is not affirmative, <i>rm</i> shall do nothing more with the current file, and go on to any remaining files.</p>
</li>
</ol>
</li>
<li>
<p>If <i>file</i> is not of type directory, the <b>-f</b> option is not specified, and either the permissions of <i>file</i> do not
permit writing and the standard input is a terminal or the <b>-i</b> option is specified, <i>rm</i> shall write a prompt to the
standard error and read a line from the standard input. If the response is not affirmative, <i>rm</i> shall do nothing more with
the current file and go on to any remaining files.</p>
</li>
<li>
<p>If the current file is a directory, <i>rm</i> shall perform actions equivalent to the <a href=
"../functions/rmdir.html"><i>rmdir</i>()</a> function defined in the System Interfaces volume of IEEE&nbsp;Std&nbsp;1003.1-2001
called with a pathname of the current file used as the <i>path</i> argument. If the current file is not a directory, <i>rm</i>
shall perform actions equivalent to the <a href="../functions/unlink.html"><i>unlink</i>()</a> function defined in the System
Interfaces volume of IEEE&nbsp;Std&nbsp;1003.1-2001 called with a pathname of the current file used as the <i>path</i>
argument.</p>
<p>If this fails for any reason, <i>rm</i> shall write a diagnostic message to standard error, do nothing more with the current
file, and go on to any remaining files.</p>
</li>
</ol>
<p>The <i>rm</i> 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).</p>
</blockquote>
<h4><a name="tag_04_121_04"></a>OPTIONS</h4>
<blockquote>
<p>The <i>rm</i> utility shall conform to the Base Definitions volume of IEEE&nbsp;Std&nbsp;1003.1-2001, <a href=
"../basedefs/xbd_chap12.html#tag_12_02">Section 12.2, Utility Syntax Guidelines</a>.</p>
<p>The following options shall be supported:</p>
<dl compact>
<dt><b>-f</b></dt>
<dd>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 <b>-i</b> option shall be ignored.</dd>
<dt><b>-i</b></dt>
<dd>Prompt for confirmation as described previously. Any previous occurrences of the <b>-f</b> option shall be ignored.</dd>
<dt><b>-R</b></dt>
<dd>Remove file hierarchies. See the DESCRIPTION.</dd>
<dt><b>-r</b></dt>
<dd>Equivalent to <b>-R</b>.</dd>
</dl>
</blockquote>
<h4><a name="tag_04_121_05"></a>OPERANDS</h4>
<blockquote>
<p>The following operand shall be supported:</p>
<dl compact>
<dt><i>file</i></dt>
<dd>A pathname of a directory entry to be removed.</dd>
</dl>
</blockquote>
<h4><a name="tag_04_121_06"></a>STDIN</h4>
<blockquote>
<p>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.</p>
</blockquote>
<h4><a name="tag_04_121_07"></a>INPUT FILES</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_121_08"></a>ENVIRONMENT VARIABLES</h4>
<blockquote>
<p>The following environment variables shall affect the execution of <i>rm</i>:</p>
<dl compact>
<dt><i>LANG</i></dt>
<dd>Provide a default value for the internationalization variables that are unset or null. (See the Base Definitions volume of
IEEE&nbsp;Std&nbsp;1003.1-2001, <a href="../basedefs/xbd_chap08.html#tag_08_02">Section 8.2, Internationalization Variables</a> for
the precedence of internationalization variables used to determine the values of locale categories.)</dd>
<dt><i>LC_ALL</i></dt>
<dd>If set to a non-empty string value, override the values of all the other internationalization variables.</dd>
<dt><i>LC_COLLATE</i></dt>
<dd><br>
Determine the locale for the behavior of ranges, equivalence classes, and multi-character collating elements used in the extended
regular expression defined for the <b>yesexpr</b> locale keyword in the <i>LC_MESSAGES</i> category.</dd>
<dt><i>LC_CTYPE</i></dt>
<dd>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 <b>yesexpr</b> locale keyword in the <i>LC_MESSAGES</i> category.</dd>
<dt><i>LC_MESSAGES</i></dt>
<dd>Determine the locale for the processing of affirmative responses that should be used to affect the format and contents of
diagnostic messages written to standard error.</dd>
<dt><i>NLSPATH</i></dt>
<dd><sup>[<a href="javascript:open_code('XSI')">XSI</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
Determine the location of message catalogs for the processing of <i>LC_MESSAGES .</i> <img src="../images/opt-end.gif" alt=
"[Option End]" border="0"></dd>
</dl>
</blockquote>
<h4><a name="tag_04_121_09"></a>ASYNCHRONOUS EVENTS</h4>
<blockquote>
<p>Default.</p>
</blockquote>
<h4><a name="tag_04_121_10"></a>STDOUT</h4>
<blockquote>
<p>Not used.</p>
</blockquote>
<h4><a name="tag_04_121_11"></a>STDERR</h4>
<blockquote>
<p>Prompts shall be written to standard error under the conditions specified in the DESCRIPTION and OPTIONS sections. The prompts
shall contain the <i>file</i> pathname, but their format is otherwise unspecified. The standard error also shall be used for
diagnostic messages.</p>
</blockquote>
<h4><a name="tag_04_121_12"></a>OUTPUT FILES</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_121_13"></a>EXTENDED DESCRIPTION</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_121_14"></a>EXIT STATUS</h4>
<blockquote>
<p>The following exit values shall be returned:</p>
<dl compact>
<dt>&nbsp;0</dt>
<dd>All of the named directory entries for which <i>rm</i> performed actions equivalent to the <a href=
"../functions/rmdir.html"><i>rmdir</i>()</a> or <a href="../functions/unlink.html"><i>unlink</i>()</a> functions were removed.</dd>
<dt>&gt;0</dt>
<dd>An error occurred.</dd>
</dl>
</blockquote>
<h4><a name="tag_04_121_15"></a>CONSEQUENCES OF ERRORS</h4>
<blockquote>
<p>Default.</p>
</blockquote>
<hr>
<div class="box"><em>The following sections are informative.</em></div>
<h4><a name="tag_04_121_16"></a>APPLICATION USAGE</h4>
<blockquote>
<p>The <i>rm</i> utility is forbidden to remove the names dot and dot-dot in order to avoid the consequences of inadvertently doing
something like:</p>
<pre>
<tt>rm -r .*
</tt>
</pre>
<p>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 <a href="../functions/unlink.html"><i>unlink</i>()</a> function defined in the System Interfaces volume of
IEEE&nbsp;Std&nbsp;1003.1-2001. Thus, the <i>rm</i> utility can fail to remove such files.</p>
<p>The <b>-i</b> option causes <i>rm</i> to prompt and read the standard input even if the standard input is not a terminal, but in
the absence of <b>-i</b> the mode prompting is not done when the standard input is not a terminal.</p>
</blockquote>
<h4><a name="tag_04_121_17"></a>EXAMPLES</h4>
<blockquote>
<ol>
<li>
<p>The following command:</p>
<pre>
<tt>rm a.out core
</tt>
</pre>
<p>removes the directory entries: <b>a.out</b> and <b>core</b>.</p>
</li>
<li>
<p>The following command:</p>
<pre>
<tt>rm -Rf junk
</tt>
</pre>
<p>removes the directory <b>junk</b> and all its contents, without prompting.</p>
</li>
</ol>
</blockquote>
<h4><a name="tag_04_121_18"></a>RATIONALE</h4>
<blockquote>
<p>For absolute clarity, paragraphs (2b) and (3) in the DESCRIPTION of <i>rm</i> describing the behavior when prompting for
confirmation, should be interpreted in the following manner:</p>
<pre>
<tt>if ((NOT f_option) AND
((not_writable AND input_is_terminal) OR i_option))
</tt>
</pre>
<p>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 <b>-f</b> option, or using the <b>-i</b> option, relies on the system to provide the most suitable dialog
directly with the user, based on the behavior specified.</p>
<p>The <b>-r</b> option is historical practice on all known systems. The synonym <b>-R</b> option is provided for consistency with
the other utilities in this volume of IEEE&nbsp;Std&nbsp;1003.1-2001 that provide options requesting recursive descent through the
file hierarchy.</p>
<p>The behavior of the <b>-f</b> option in historical versions of <i>rm</i> is inconsistent. In general, along with &quot;forcing&quot; 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 <b>-f</b> option suppresses usage
messages and system errors as well. Suppressing such messages is not a service to either shell scripts or users.</p>
<p>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 IEEE&nbsp;Std&nbsp;1003.1-2001 does not permit the <b>-f</b> option to suppress such
messages.</p>
<p>When given the <b>-r</b> and <b>-i</b> options, historical versions of <i>rm</i> 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 &quot;prune&quot; the file hierarchy walk. Historical versions of <i>rm</i> 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 <b>-i</b> option was specified and the
permissions of the file did not permit writing. The POSIX Shell and Utilities <i>rm</i> differs little from historic practice, but
does require that prompts be consistent. Historical versions of <i>rm</i> were also inconsistent in that prompts were done to both
standard output and standard error. This volume of IEEE&nbsp;Std&nbsp;1003.1-2001 requires that prompts be done to standard error,
for consistency with <a href="../utilities/cp.html"><i>cp</i></a> and <a href="../utilities/mv.html"><i>mv</i></a>, and to allow
historical extensions to <i>rm</i> that provide an option to list deleted files on standard output.</p>
<p>The <i>rm</i> utility is required to descend to arbitrary depths so that any file hierarchy may be deleted. This means, for
example, that the <i>rm</i> utility cannot run out of file descriptors during its descent (that is, if the number of file
descriptors is limited, <i>rm</i> cannot be implemented in the historical fashion where one file descriptor is used per directory
level). Also, <i>rm</i> is not permitted to fail because of path length restrictions, unless an operand specified by the user is
longer than {PATH_MAX}.</p>
<p>The <i>rm</i> utility removes symbolic links themselves, not the files they refer to, as a consequence of the dependence on the
<a href="../functions/unlink.html"><i>unlink</i>()</a> functionality, per the DESCRIPTION. When removing hierarchies with <b>-r</b>
or <b>-R</b>, the prohibition on following symbolic links has to be made explicit.</p>
</blockquote>
<h4><a name="tag_04_121_19"></a>FUTURE DIRECTIONS</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_121_20"></a>SEE ALSO</h4>
<blockquote>
<p><a href="rmdir.html"><i>rmdir</i>()</a> , the System Interfaces volume of IEEE&nbsp;Std&nbsp;1003.1-2001, <a href=
"../functions/remove.html"><i>remove</i>()</a>, <a href="../functions/rmdir.html"><i>rmdir</i>()</a>, <a href=
"../functions/unlink.html"><i>unlink</i>()</a></p>
</blockquote>
<h4><a name="tag_04_121_21"></a>CHANGE HISTORY</h4>
<blockquote>
<p>First released in Issue 2.</p>
</blockquote>
<h4><a name="tag_04_121_22"></a>Issue 5</h4>
<blockquote>
<p>The FUTURE DIRECTIONS section is added.</p>
</blockquote>
<h4><a name="tag_04_121_23"></a>Issue 6</h4>
<blockquote>
<p>Text is added to clarify actions relating to symbolic links as specified in the IEEE&nbsp;P1003.2b draft standard.</p>
</blockquote>
<div class="box"><em>End of informative text.</em></div>
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