<html lang="en">
<head>
<title>Frame Apply - Debugging with GDB</title>
<meta http-equiv="Content-Type" content="text/html">
<meta name="description" content="Debugging with GDB">
<meta name="generator" content="makeinfo 4.13">
<link title="Top" rel="start" href="index.html#Top">
<link rel="up" href="Stack.html#Stack" title="Stack">
<link rel="prev" href="Frame-Info.html#Frame-Info" title="Frame Info">
<link rel="next" href="Frame-Filter-Management.html#Frame-Filter-Management" title="Frame Filter Management">
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
<!--
Copyright (C) 1988-2019 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with the
Invariant Sections being ``Free Software'' and ``Free Software Needs
Free Documentation'', with the Front-Cover Texts being ``A GNU Manual,''
and with the Back-Cover Texts as in (a) below.

(a) The FSF's Back-Cover Text is: ``You are free to copy and modify
this GNU Manual.  Buying copies from GNU Press supports the FSF in
developing GNU and promoting software freedom.''
-->
<meta http-equiv="Content-Style-Type" content="text/css">
<style type="text/css"><!--
  pre.display { font-family:inherit }
  pre.format  { font-family:inherit }
  pre.smalldisplay { font-family:inherit; font-size:smaller }
  pre.smallformat  { font-family:inherit; font-size:smaller }
  pre.smallexample { font-size:smaller }
  pre.smalllisp    { font-size:smaller }
  span.sc    { font-variant:small-caps }
  span.roman { font-family:serif; font-weight:normal; } 
  span.sansserif { font-family:sans-serif; font-weight:normal; } 
--></style>
</head>
<body>
<div class="node">
<a name="Frame-Apply"></a>
<p>
Next:&nbsp;<a rel="next" accesskey="n" href="Frame-Filter-Management.html#Frame-Filter-Management">Frame Filter Management</a>,
Previous:&nbsp;<a rel="previous" accesskey="p" href="Frame-Info.html#Frame-Info">Frame Info</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="Stack.html#Stack">Stack</a>
<hr>
</div>

<h3 class="section">8.5 Applying a Command to Several Frames.</h3>

<p><a name="index-frame-apply-545"></a><a name="index-apply-command-to-several-frames-546"></a>
     <dl>
<dt><code>frame apply [all | </code><var>count</var><code> | </code><var>-count</var><code> | level </code><var>level</var><code>...] [</code><var>flag</var><code>]... </code><var>command</var><dd>The <code>frame apply</code> command allows you to apply the named
<var>command</var> to one or more frames.

          <dl>
<dt><code>all</code><dd>Specify <code>all</code> to apply <var>command</var> to all frames.

          <br><dt><var>count</var><dd>Use <var>count</var> to apply <var>command</var> to the innermost <var>count</var>
frames, where <var>count</var> is a positive number.

          <br><dt><var>-count</var><dd>Use <var>-count</var> to apply <var>command</var> to the outermost <var>count</var>
frames, where <var>count</var> is a positive number.

          <br><dt><code>level</code><dd>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><span class="samp">backtrace</span></samp>&rsquo; command output. 
E.g., &lsquo;<samp><span class="samp">2-4 6-8 3</span></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.

     </dl>

   </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
See <a href="Backtrace.html#Backtrace">Backtraces</a>.

   <p>The <var>flag</var> arguments control what output to produce and how to handle
errors raised when applying <var>command</var> to a frame.  <var>flag</var>
must start with a <code>-</code> directly followed by one letter in
<code>qcs</code>.  If several flags are provided, they must be given
individually, such as <code>-c -q</code>.

   <p>By default, <span class="sc">gdb</span> 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 flags can be used to fine-tune this behavior:

     <dl>
<dt><code>-c</code><dd>The flag <code>-c</code>, which stands for &lsquo;<samp><span class="samp">continue</span></samp>&rsquo;, causes any
errors in <var>command</var> to be displayed, and the execution of
<code>frame apply</code> then continues. 
<br><dt><code>-s</code><dd>The flag <code>-s</code>, which stands for &lsquo;<samp><span class="samp">silent</span></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. 
<br><dt><code>-q</code><dd>The flag <code>-q</code> (&lsquo;<samp><span class="samp">quiet</span></samp>&rsquo;) disables printing the frame
information. 
</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.

<pre class="smallexample">     (gdb) frame apply all p j
     #0  some_function (i=5) at fun.c:4
     No symbol "j" in current context.
     (gdb) frame apply all -c p j
     #0  some_function (i=5) at fun.c:4
     No symbol "j" 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>
   <p>By default, &lsquo;<samp><span class="samp">frame apply</span></samp>&rsquo;, prints the frame location
information before the command output:

<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>
   <p>If flag <code>-q</code> is given, no frame information is printed:
<pre class="smallexample">     (gdb) frame apply all -q p $sp
     $12 = (void *) 0xffffd1e0
     $13 = (void *) 0xffffd1f0
     (gdb)
</pre>
     
<a name="index-faas-547"></a>
<a name="index-apply-a-command-to-all-frames-_0028ignoring-errors-and-empty-output_0029-548"></a>
<dl><dt><code>faas </code><var>command</var><dd>Shortcut for <code>frame apply all -s </code><var>command</var>. 
Applies <var>command</var> on all frames, ignoring errors and empty output.

     <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:
     <pre class="smallexample">          (gdb) faas p some_local_var_i_do_not_remember_where_it_is
</pre>
     <p>Note that the command <code>tfaas </code><var>command</var> applies <var>command</var>
on all frames of all threads.  See See <a href="Threads.html#Threads">Threads</a>. 
</dl>

   </body></html>