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<h4 class="subsection">27.6.6 Continuing Stopped Jobs</h4>

<p><a name="index-stopped-jobs_002c-continuing-3225"></a>The shell can continue a stopped job by sending a <code>SIGCONT</code> signal
to its process group.  If the job is being continued in the foreground,
the shell should first invoke <code>tcsetpgrp</code> to give the job access to
the terminal, and restore the saved terminal settings.  After continuing
a job in the foreground, the shell should wait for the job to stop or
complete, as if the job had just been launched in the foreground.

   <p>The sample shell program handles both newly created and continued jobs
with the same pair of functions, <code>put_job_in_foreground</code><!-- /@w --> and
<code>put_job_in_background</code><!-- /@w -->.  The definitions of these functions
were given in <a href="Foreground-and-Background.html#Foreground-and-Background">Foreground and Background</a>.  When continuing a
stopped job, a nonzero value is passed as the <var>cont</var> argument to
ensure that the <code>SIGCONT</code> signal is sent and the terminal modes
reset, as appropriate.

   <p>This leaves only a function for updating the shell's internal bookkeeping
about the job being continued:

<pre class="smallexample">     /* <span class="roman">Mark a stopped job J as being running again.</span>  */
     
     void
     mark_job_as_running (job *j)
     {
       Process *p;
     
       for (p = j-&gt;first_process; p; p = p-&gt;next)
         p-&gt;stopped = 0;
       j-&gt;notified = 0;
     }
     
     /* <span class="roman">Continue the job J.</span>  */
     
     void
     continue_job (job *j, int foreground)
     {
       mark_job_as_running (j);
       if (foreground)
         put_job_in_foreground (j, 1);
       else
         put_job_in_background (j, 1);
     }
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