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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>
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<hr size="2" noshade>
<h4><a name="tag_04_70_01"></a>NAME</h4>
<blockquote>jobs - display status of jobs in the current session</blockquote>
<h4><a name="tag_04_70_02"></a>SYNOPSIS</h4>
<blockquote class="synopsis">
<div class="box"><code><tt><sup>[<a href="javascript:open_code('UP')">UP</a>]</sup> <img src="../images/opt-start.gif" alt=
"[Option Start]" border="0"> jobs</tt> <b>[</b><tt>-l| -p</tt><b>][</b><i>job_id</i><tt>...</tt><b>]</b><tt><img src=
"../images/opt-end.gif" alt="[Option End]" border="0"></tt></code></div>
</blockquote>
<h4><a name="tag_04_70_03"></a>DESCRIPTION</h4>
<blockquote>
<p>The <i>jobs</i> utility shall display the status of jobs that were started in the current shell environment; see <a href=
"xcu_chap02.html#tag_02_12"><i>Shell Execution Environment</i></a> .</p>
<p>When <i>jobs</i> reports the termination status of a job, the shell shall remove its process ID from the list of those &quot;known
in the current shell execution environment''; see <a href="xcu_chap02.html#tag_02_09_03_02"><i>Asynchronous Lists</i></a> .</p>
</blockquote>
<h4><a name="tag_04_70_04"></a>OPTIONS</h4>
<blockquote>
<p>The <i>jobs</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>-l</b></dt>
<dd>(The letter ell.) Provide more information about each job listed. This information shall include the job number, current job,
process group ID, state, and the command that formed the job.</dd>
<dt><b>-p</b></dt>
<dd>Display only the process IDs for the process group leaders of the selected jobs.</dd>
</dl>
<p>By default, the <i>jobs</i> utility shall display the status of all stopped jobs, running background jobs and all jobs whose
status has changed and have not been reported by the shell.</p>
</blockquote>
<h4><a name="tag_04_70_05"></a>OPERANDS</h4>
<blockquote>
<p>The following operand shall be supported:</p>
<dl compact>
<dt><i>job_id</i></dt>
<dd>Specifies the jobs for which the status is to be displayed. If no <i>job_id</i> is given, the status information for all jobs
shall be displayed. The format of <i>job_id</i> is described in the Base Definitions volume of IEEE&nbsp;Std&nbsp;1003.1-2001, <a
href="../basedefs/xbd_chap03.html#tag_03_203">Section 3.203, Job Control Job ID</a>.</dd>
</dl>
</blockquote>
<h4><a name="tag_04_70_06"></a>STDIN</h4>
<blockquote>
<p>Not used.</p>
</blockquote>
<h4><a name="tag_04_70_07"></a>INPUT FILES</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_70_08"></a>ENVIRONMENT VARIABLES</h4>
<blockquote>
<p>The following environment variables shall affect the execution of <i>jobs</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_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).</dd>
<dt><i>LC_MESSAGES</i></dt>
<dd>Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error and
informative messages written to standard output.</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_70_09"></a>ASYNCHRONOUS EVENTS</h4>
<blockquote>
<p>Default.</p>
</blockquote>
<h4><a name="tag_04_70_10"></a>STDOUT</h4>
<blockquote>
<p>If the <b>-p</b> option is specified, the output shall consist of one line for each process ID:</p>
<pre>
<tt>"%d\n", &lt;</tt><i>process ID</i><tt>&gt;
</tt>
</pre>
<p>Otherwise, if the <b>-l</b> option is not specified, the output shall be a series of lines of the form:</p>
<pre>
<tt>"[%d] %c %s %s\n", &lt;</tt><i>job-number</i><tt>&gt;, &lt;</tt><i>current</i><tt>&gt;, &lt;</tt><i>state</i><tt>&gt;, &lt;</tt><i>command</i><tt>&gt;
</tt>
</pre>
<p>where the fields shall be as follows:</p>
<dl compact>
<dt>&lt;<i>current</i>&gt;</dt>
<dd>The character <tt>'+'</tt> identifies the job that would be used as a default for the <a href=
"../utilities/fg.html"><i>fg</i></a> or <a href="../utilities/bg.html"><i>bg</i></a> utilities; this job can also be specified
using the <i>job_id</i> %+ or <tt>"%%"</tt> . The character <tt>'-'</tt> identifies the job that would become the default if the
current default job were to exit; this job can also be specified using the <i>job_id</i> %-. For other jobs, this field is a
&lt;space&gt;. At most one job can be identified with <tt>'+'</tt> and at most one job can be identified with <tt>'-'</tt> . If
there is any suspended job, then the current job shall be a suspended job. If there are at least two suspended jobs, then the
previous job also shall be a suspended job.</dd>
<dt>&lt;<i>job-number</i>&gt;</dt>
<dd>A number that can be used to identify the process group to the <a href="../utilities/wait.html"><i>wait</i></a>, <a href=
"../utilities/fg.html"><i>fg</i></a>, <a href="../utilities/bg.html"><i>bg</i></a>, and <a href=
"../utilities/kill.html"><i>kill</i></a> utilities. Using these utilities, the job can be identified by prefixing the job number
with <tt>'%'</tt> .</dd>
<dt>&lt;<i>state</i>&gt;</dt>
<dd>One of the following strings (in the POSIX locale):
<dl compact>
<dt><b>Running</b></dt>
<dd>Indicates that the job has not been suspended by a signal and has not exited.</dd>
<dt><b>Done</b></dt>
<dd>Indicates that the job completed and returned exit status zero.</dd>
<dt><b>Done</b>(<i>code</i>)</dt>
<dd>Indicates that the job completed normally and that it exited with the specified non-zero exit status, <i>code</i>, expressed as
a decimal number.</dd>
<dt><b>Stopped</b></dt>
<dd>Indicates that the job was suspended by the SIGTSTP signal.</dd>
<dt><b>Stopped</b>&nbsp;(<b>SIGTSTP</b>)</dt>
<dd><br>
Indicates that the job was suspended by the SIGTSTP signal.</dd>
<dt><b>Stopped</b>&nbsp;(<b>SIGSTOP</b>)</dt>
<dd><br>
Indicates that the job was suspended by the SIGSTOP signal.</dd>
<dt><b>Stopped</b>&nbsp;(<b>SIGTTIN</b>)</dt>
<dd><br>
Indicates that the job was suspended by the SIGTTIN signal.</dd>
<dt><b>Stopped</b>&nbsp;(<b>SIGTTOU</b>)</dt>
<dd><br>
Indicates that the job was suspended by the SIGTTOU signal.</dd>
</dl>
<p>The implementation may substitute the string <b>Suspended</b> in place of <b>Stopped</b>. If the job was terminated by a signal,
the format of &lt;<i>state</i>&gt; is unspecified, but it shall be visibly distinct from all of the other &lt;<i>state</i>&gt;
formats shown here and shall indicate the name or description of the signal causing the termination.</p>
</dd>
<dt>&lt;<i>command</i>&gt;</dt>
<dd>The associated command that was given to the shell.</dd>
</dl>
<p>If the <b>-l</b> option is specified, a field containing the process group ID shall be inserted before the &lt;<i>state</i>&gt;
field. Also, more processes in a process group may be output on separate lines, using only the process ID and
&lt;<i>command</i>&gt; fields.</p>
</blockquote>
<h4><a name="tag_04_70_11"></a>STDERR</h4>
<blockquote>
<p>The standard error shall be used only for diagnostic messages.</p>
</blockquote>
<h4><a name="tag_04_70_12"></a>OUTPUT FILES</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_70_13"></a>EXTENDED DESCRIPTION</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_70_14"></a>EXIT STATUS</h4>
<blockquote>
<p>The following exit values shall be returned:</p>
<dl compact>
<dt>&nbsp;0</dt>
<dd>Successful completion.</dd>
<dt>&gt;0</dt>
<dd>An error occurred.</dd>
</dl>
</blockquote>
<h4><a name="tag_04_70_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_70_16"></a>APPLICATION USAGE</h4>
<blockquote>
<p>The <b>-p</b> option is the only portable way to find out the process group of a job because different implementations have
different strategies for defining the process group of the job. Usage such as $( <i>jobs</i> <b>-p</b>) provides a way of referring
to the process group of the job in an implementation-independent way.</p>
<p>The <i>jobs</i> utility does not work as expected when it is operating in its own utility execution environment because that
environment has no applicable jobs to manipulate. See the APPLICATION USAGE section for <a href="bg.html"><i>bg</i></a> . For this
reason, <i>jobs</i> is generally implemented as a shell regular built-in.</p>
</blockquote>
<h4><a name="tag_04_70_17"></a>EXAMPLES</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_70_18"></a>RATIONALE</h4>
<blockquote>
<p>Both <tt>"%%"</tt> and <tt>"%+"</tt> are used to refer to the current job. Both forms are of equal validity-the <tt>"%%"</tt>
mirroring <tt>"$$"</tt> and <tt>"%+"</tt> mirroring the output of <i>jobs</i>. Both forms reflect historical practice of the
KornShell and the C shell with job control.</p>
<p>The job control features provided by <a href="../utilities/bg.html"><i>bg</i></a>, <a href="../utilities/fg.html"><i>fg</i></a>,
and <i>jobs</i> are based on the KornShell. The standard developers examined the characteristics of the C shell versions of these
utilities and found that differences exist. Despite widespread use of the C shell, the KornShell versions were selected for this
volume of IEEE&nbsp;Std&nbsp;1003.1-2001 to maintain a degree of uniformity with the rest of the KornShell features selected (such
as the very popular command line editing features).</p>
<p>The <i>jobs</i> utility is not dependent on the job control option, as are the seemingly related <a href=
"../utilities/bg.html"><i>bg</i></a> and <a href="../utilities/fg.html"><i>fg</i></a> utilities because <i>jobs</i> is useful for
examining background jobs, regardless of the condition of job control. When the user has invoked a <a href=
"../utilities/set.html"><i>set</i></a> <b>+m</b> command and job control has been turned off, <i>jobs</i> can still be
used to examine the background jobs associated with that current session. Similarly, <a href=
"../utilities/kill.html"><i>kill</i></a> can then be used to kill background jobs with <a href=
"../utilities/kill.html"><i>kill</i></a>% &lt;<i>background job number</i>&gt;.</p>
<p>The output for terminated jobs is left unspecified to accommodate various historical systems. The following formats have been
witnessed:</p>
<ol>
<li>
<p><b>Killed</b>( <i>signal name</i>)</p>
</li>
<li>
<p><i>signal name</i></p>
</li>
<li>
<p><i>signal name</i>( <b>coredump</b>)</p>
</li>
<li>
<p><i>signal description</i>- <b>core dumped</b></p>
</li>
</ol>
<p>Most users should be able to understand these formats, although it means that applications have trouble parsing them.</p>
<p>The calculation of job IDs was not described since this would suggest an implementation, which may impose unnecessary
restrictions.</p>
<p>In an early proposal, a <b>-n</b> option was included to &quot;Display the status of jobs that have changed, exited, or stopped
since the last status report&quot;. It was removed because the shell always writes any changed status of jobs before each prompt.</p>
</blockquote>
<h4><a name="tag_04_70_19"></a>FUTURE DIRECTIONS</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_04_70_20"></a>SEE ALSO</h4>
<blockquote>
<p><a href="xcu_chap02.html#tag_02_12"><i>Shell Execution Environment</i></a> , <a href="bg.html"><i>bg</i></a> , <a href=
"fg.html"><i>fg</i></a> , <a href="kill.html"><i>kill</i>()</a> , <a href="wait.html"><i>wait</i>()</a></p>
</blockquote>
<h4><a name="tag_04_70_21"></a>CHANGE HISTORY</h4>
<blockquote>
<p>First released in Issue 4.</p>
</blockquote>
<h4><a name="tag_04_70_22"></a>Issue 6</h4>
<blockquote>
<p>This utility is marked as part of the User Portability Utilities option.</p>
<p>The JC shading is removed as job control is mandatory in this issue.</p>
</blockquote>
<div class="box"><em>End of informative text.</em></div>
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