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<a name="Linespec-Locations"></a>
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<p>
Next: <a href="Explicit-Locations.html#Explicit-Locations" accesskey="n" rel="next">Explicit Locations</a>, Up: <a href="Specify-Location.html#Specify-Location" accesskey="u" rel="up">Specify Location</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>
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<hr>
<a name="Linespec-Locations-1"></a>
<h4 class="subsection">9.2.1 Linespec Locations</h4>
<a name="index-linespec-locations"></a>

<p>A <em>linespec</em> is a colon-separated list of source location parameters such
as file name, function name, etc.  Here are all the different ways of
specifying a linespec:
</p>
<dl compact="compact">
<dt><code><var>linenum</var></code></dt>
<dd><p>Specifies the line number <var>linenum</var> of the current source file.
</p>
</dd>
<dt><code>-<var>offset</var></code></dt>
<dt><code>+<var>offset</var></code></dt>
<dd><p>Specifies the line <var>offset</var> lines before or after the <em>current
line</em>.  For the <code>list</code> command, the current line is the last one
printed; for the breakpoint commands, this is the line at which
execution stopped in the currently selected <em>stack frame</em>
(see <a href="Frames.html#Frames">Frames</a>, for a description of stack frames.)  When
used as the second of the two linespecs in a <code>list</code> command,
this specifies the line <var>offset</var> lines up or down from the first
linespec.
</p>
</dd>
<dt><code><var>filename</var>:<var>linenum</var></code></dt>
<dd><p>Specifies the line <var>linenum</var> in the source file <var>filename</var>.
If <var>filename</var> is a relative file name, then it will match any
source file name with the same trailing components.  For example, if
<var>filename</var> is &lsquo;<samp>gcc/expr.c</samp>&rsquo;, then it will match source file
name of <samp>/build/trunk/gcc/expr.c</samp>, but not
<samp>/build/trunk/libcpp/expr.c</samp> or <samp>/build/trunk/gcc/x-expr.c</samp>.
</p>
</dd>
<dt><code><var>function</var></code></dt>
<dd><p>Specifies the line that begins the body of the function <var>function</var>.
For example, in C, this is the line with the open brace.
</p>
<p>By default, in C<tt>++</tt> and Ada, <var>function</var> is interpreted as
specifying all functions named <var>function</var> in all scopes.  For
C<tt>++</tt>, this means in all namespaces and classes.  For Ada, this
means in all packages.
</p>
<p>For example, assuming a program with C<tt>++</tt> symbols named
<code>A::B::func</code> and <code>B::func</code>, both commands <kbd>break&nbsp;func</kbd><!-- /@w --> and <kbd>break&nbsp;B::func</kbd><!-- /@w --> set a breakpoint on both symbols.
</p>
<p>Commands that accept a linespec let you override this with the
<code>-qualified</code> option.  For example, <kbd>break&nbsp;<span class="nolinebreak">-qualified</span>&nbsp;func</kbd><!-- /@w --> sets a breakpoint on a free-function named <code>func</code> ignoring
any C<tt>++</tt> class methods and namespace functions called <code>func</code>.
</p>
<p>See <a href="Explicit-Locations.html#Explicit-Locations">Explicit Locations</a>.
</p>
</dd>
<dt><code><var>function</var>:<var>label</var></code></dt>
<dd><p>Specifies the line where <var>label</var> appears in <var>function</var>.
</p>
</dd>
<dt><code><var>filename</var>:<var>function</var></code></dt>
<dd><p>Specifies the line that begins the body of the function <var>function</var>
in the file <var>filename</var>.  You only need the file name with a
function name to avoid ambiguity when there are identically named
functions in different source files.
</p>
</dd>
<dt><code><var>label</var></code></dt>
<dd><p>Specifies the line at which the label named <var>label</var> appears
in the function corresponding to the currently selected stack frame.
If there is no current selected stack frame (for instance, if the inferior
is not running), then <small>GDB</small> will not search for a label.
</p>
<a name="index-breakpoint-at-static-probe-point"></a>
</dd>
<dt><code>-pstap|-probe-stap <span class="roman">[</span><var>objfile</var>:<span class="roman">[</span><var>provider</var>:<span class="roman">]</span><span class="roman">]</span><var>name</var></code></dt>
<dd><p>The <small>GNU</small>/Linux tool <code>SystemTap</code> provides a way for
applications to embed static probes.  See <a href="Static-Probe-Points.html#Static-Probe-Points">Static Probe Points</a>, for more
information on finding and using static probes.  This form of linespec
specifies the location of such a static probe.
</p>
<p>If <var>objfile</var> is given, only probes coming from that shared library
or executable matching <var>objfile</var> as a regular expression are considered.
If <var>provider</var> is given, then only probes from that provider are considered.
If several probes match the spec, <small>GDB</small> will insert a breakpoint at
each one of those probes.
</p></dd>
</dl>

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Next: <a href="Explicit-Locations.html#Explicit-Locations" accesskey="n" rel="next">Explicit Locations</a>, Up: <a href="Specify-Location.html#Specify-Location" accesskey="u" rel="up">Specify Location</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>
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