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<h1 class="SECT1"><a id="PROCESS-CONTROL-FOREGROUNDING"
name="PROCESS-CONTROL-FOREGROUNDING">11.2 Foregrounding</a></h1>
<p>If you need to interact with a backgrounded process, you can bring it back into the
foreground. If you've only got one backgrounded process, you can bring it back by
typing:</p>
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<samp class="PROMPT">%</samp> <kbd class="USERINPUT">fg</kbd>
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<p>If the program is not done running, the program will take control over you terminal
and you will not be returned to a prompt. Sometimes, the program will finish running
while backgrounded. In this instance, you'll get a message like this:</p>
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[1]+ Done /bin/ls $LS_OPTIONS
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<p>That tells you that the backgrounded process (in this case <tt class="COMMAND">ls</tt>
- not terribly interesting) has completed.</p>
<p>It is possible to have several processes backgrounded at once. When this happens,
you'll need to know which process you want to bring back to the foreground. Just typing
<tt class="COMMAND">fg</tt> will foreground the process that was last backgrounded. What
if you had a whole list of processes in the background? Luckily, bash includes a command
to list all the processes. It's called <tt class="COMMAND">jobs</tt> and gives output
like so:</p>
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<samp class="PROMPT">%</samp> <kbd class="USERINPUT">jobs</kbd>
[1] Stopped vim
[2]- Stopped amp
[3]+ Stopped man ps
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<p>This shows you a list of all the processes that are backgrounded. As you can see, they
are all stopped. This means that the processes are suspended. The number is a sort of ID
for all the backgrounded processes. The ID with a plus sign beside it (<var
class="LITERAL">man ps</var>) is the process that will be foregrounded if you just type
<tt class="COMMAND">fg</tt>.</p>
<p>If you wanted to foreground <tt class="COMMAND">vim</tt>, you would type:</p>
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<samp class="PROMPT">%</samp> <kbd class="USERINPUT">fg 1</kbd>
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<p>and <tt class="COMMAND">vim</tt> would spring back up to the console. Backgrounding
processes can be very useful if you only have one terminal open over a dialup connection.
You can have several programs running on that one terminal, periodically switching back
and forth between them.</p>
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