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<a name="Frame-Apply"></a>
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<p>
Next: <a href="Frame-Filter-Management.html#Frame-Filter-Management" accesskey="n" rel="next">Frame Filter Management</a>, Previous: <a href="Frame-Info.html#Frame-Info" accesskey="p" rel="previous">Frame Info</a>, Up: <a href="Stack.html#Stack" accesskey="u" rel="up">Stack</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<a name="Applying-a-Command-to-Several-Frames_002e"></a>
<h3 class="section">8.5 Applying a Command to Several Frames.</h3>
<a name="index-frame-apply"></a>
<a name="index-apply-command-to-several-frames"></a>
<dl compact="compact">
<dt><code>frame apply [all | <var>count</var> | <var>-count</var> | level <var>level</var>&hellip;] [<var>option</var>]&hellip; <var>command</var></code></dt>
<dd><p>The <code>frame apply</code> command allows you to apply the named
<var>command</var> to one or more frames.
</p>
<dl compact="compact">
<dt><code><code>all</code></code></dt>
<dd><p>Specify <code>all</code> to apply <var>command</var> to all frames.
</p>
</dd>
<dt><code><var>count</var></code></dt>
<dd><p>Use <var>count</var> to apply <var>command</var> to the innermost <var>count</var>
frames, where <var>count</var> is a positive number.
</p>
</dd>
<dt><code><var>-count</var></code></dt>
<dd><p>Use <var>-count</var> to apply <var>command</var> to the outermost <var>count</var>
frames, where <var>count</var> is a positive number.
</p>
</dd>
<dt><code><code>level</code></code></dt>
<dd><p>Use <code>level</code> to apply <var>command</var> to the set of frames identified
by the <var>level</var> list.  <var>level</var> is a frame level or a range of frame
levels as <var>level1</var>-<var>level2</var>.  The frame level is the number shown
in the first field of the &lsquo;<samp>backtrace</samp>&rsquo; command output.
E.g., &lsquo;<samp>2-4 6-8 3</samp>&rsquo; indicates to apply <var>command</var> for the frames
at levels 2, 3, 4, 6, 7, 8, and then again on frame at level 3.
</p>
</dd>
</dl>

<p>Note that the frames on which <code>frame apply</code> applies a command are
also influenced by the <code>set backtrace</code> settings such as <code>set
backtrace past-main</code> and <code>set backtrace limit N</code>.
See <a href="Backtrace.html#Backtrace">Backtraces</a>.
</p>
<p>The <code>frame apply</code> command also supports a number of options that
allow overriding relevant <code>set backtrace</code> settings:
</p>
<dl compact="compact">
<dt><code>-past-main [<code>on</code>|<code>off</code>]</code></dt>
<dd><p>Whether backtraces should continue past <code>main</code>.
Related setting: <a href="Backtrace.html#set-backtrace-past_002dmain">set backtrace past-main</a>.
</p>
</dd>
<dt><code>-past-entry [<code>on</code>|<code>off</code>]</code></dt>
<dd><p>Whether backtraces should continue past the entry point of a program.
Related setting: <a href="Backtrace.html#set-backtrace-past_002dentry">set backtrace past-entry</a>.
</p></dd>
</dl>

<p>By default, <small>GDB</small> displays some frame information before the
output produced by <var>command</var>, and an error raised during the
execution of a <var>command</var> will abort <code>frame apply</code>.  The
following options can be used to fine-tune these behaviors:
</p>
<dl compact="compact">
<dt><code>-c</code></dt>
<dd><p>The flag <code>-c</code>, which stands for &lsquo;<samp>continue</samp>&rsquo;, causes any
errors in <var>command</var> to be displayed, and the execution of
<code>frame apply</code> then continues.
</p></dd>
<dt><code>-s</code></dt>
<dd><p>The flag <code>-s</code>, which stands for &lsquo;<samp>silent</samp>&rsquo;, causes any errors
or empty output produced by a <var>command</var> to be silently ignored.
That is, the execution continues, but the frame information and errors
are not printed.
</p></dd>
<dt><code>-q</code></dt>
<dd><p>The flag <code>-q</code> (&lsquo;<samp>quiet</samp>&rsquo;) disables printing the frame
information.
</p></dd>
</dl>

<p>The following example shows how the flags <code>-c</code> and <code>-s</code> are
working when applying the command <code>p j</code> to all frames, where
variable <code>j</code> can only be successfully printed in the outermost
<code>#1 main</code> frame.
</p>
<div class="smallexample">
<pre class="smallexample">(gdb) frame apply all p j
#0  some_function (i=5) at fun.c:4
No symbol &quot;j&quot; in current context.
(gdb) frame apply all -c p j
#0  some_function (i=5) at fun.c:4
No symbol &quot;j&quot; in current context.
#1  0x565555fb in main (argc=1, argv=0xffffd2c4) at fun.c:11
$1 = 5
(gdb) frame apply all -s p j
#1  0x565555fb in main (argc=1, argv=0xffffd2c4) at fun.c:11
$2 = 5
(gdb)
</pre></div>

<p>By default, &lsquo;<samp>frame apply</samp>&rsquo;, prints the frame location
information before the command output:
</p>
<div class="smallexample">
<pre class="smallexample">(gdb) frame apply all p $sp
#0  some_function (i=5) at fun.c:4
$4 = (void *) 0xffffd1e0
#1  0x565555fb in main (argc=1, argv=0xffffd2c4) at fun.c:11
$5 = (void *) 0xffffd1f0
(gdb)
</pre></div>

<p>If the flag <code>-q</code> is given, no frame information is printed:
</p><div class="smallexample">
<pre class="smallexample">(gdb) frame apply all -q p $sp
$12 = (void *) 0xffffd1e0
$13 = (void *) 0xffffd1f0
(gdb)
</pre></div>

</dd>
</dl>

<dl compact="compact">
<dd>
<a name="index-faas"></a>
<a name="index-apply-a-command-to-all-frames-_0028ignoring-errors-and-empty-output_0029"></a>
</dd>
<dt><code>faas <var>command</var></code></dt>
<dd><p>Shortcut for <code>frame apply all -s <var>command</var></code>.
Applies <var>command</var> on all frames, ignoring errors and empty output.
</p>
<p>It can for example be used to print a local variable or a function
argument without knowing the frame where this variable or argument
is, using:
</p><div class="smallexample">
<pre class="smallexample">(gdb) faas p some_local_var_i_do_not_remember_where_it_is
</pre></div>

<p>The <code>faas</code> command accepts the same options as the <code>frame
apply</code> command.  See <a href="#Frame-Apply">frame apply</a>.
</p>
<p>Note that the command <code>tfaas <var>command</var></code> applies <var>command</var>
on all frames of all threads.  See See <a href="Threads.html#Threads">Threads</a>.
</p></dd>
</dl>


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