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<h5 class="subsubsection">15.4.7.5 Extensions for Ada Tasks</h5>

<p><a name="index-Ada_002c-tasking-868"></a>
Support for Ada tasks is analogous to that for threads (see <a href="Threads.html#Threads">Threads</a>). 
<span class="sc">gdb</span> provides the following task-related commands:

     
<a name="index-info-tasks-869"></a>
<dl><dt><code>info tasks</code><dd>This command shows a list of current Ada tasks, as in the following example:

     <pre class="smallexample">          (gdb) info tasks
            ID       TID P-ID Pri State                 Name
             1   8088000   0   15 Child Activation Wait main_task
             2   80a4000   1   15 Accept Statement      b
             3   809a800   1   15 Child Activation Wait a
          *  4   80ae800   3   15 Runnable              c
          
</pre>
     <p class="noindent">In this listing, the asterisk before the last task indicates it to be the
task currently being inspected.

          <dl>
<dt>ID<dd>Represents <span class="sc">gdb</span>'s internal task number.

          <br><dt>TID<dd>The Ada task ID.

          <br><dt>P-ID<dd>The parent's task ID (<span class="sc">gdb</span>'s internal task number).

          <br><dt>Pri<dd>The base priority of the task.

          <br><dt>State<dd>Current state of the task.

               <dl>
<dt><code>Unactivated</code><dd>The task has been created but has not been activated.  It cannot be
executing.

               <br><dt><code>Runnable</code><dd>The task is not blocked for any reason known to Ada.  (It may be waiting
for a mutex, though.) It is conceptually "executing" in normal mode.

               <br><dt><code>Terminated</code><dd>The task is terminated, in the sense of ARM 9.3 (5).  Any dependents
that were waiting on terminate alternatives have been awakened and have
terminated themselves.

               <br><dt><code>Child Activation Wait</code><dd>The task is waiting for created tasks to complete activation.

               <br><dt><code>Accept Statement</code><dd>The task is waiting on an accept or selective wait statement.

               <br><dt><code>Waiting on entry call</code><dd>The task is waiting on an entry call.

               <br><dt><code>Async Select Wait</code><dd>The task is waiting to start the abortable part of an asynchronous
select statement.

               <br><dt><code>Delay Sleep</code><dd>The task is waiting on a select statement with only a delay
alternative open.

               <br><dt><code>Child Termination Wait</code><dd>The task is sleeping having completed a master within itself, and is
waiting for the tasks dependent on that master to become terminated or
waiting on a terminate Phase.

               <br><dt><code>Wait Child in Term Alt</code><dd>The task is sleeping waiting for tasks on terminate alternatives to
finish terminating.

               <br><dt><code>Accepting RV with </code><var>taskno</var><dd>The task is accepting a rendez-vous with the task <var>taskno</var>. 
</dl>

          <br><dt>Name<dd>Name of the task in the program.

     </dl>

     <p><a name="index-info-task-_0040var_007btaskno_007d-870"></a><br><dt><code>info task </code><var>taskno</var><dd>This command shows detailled informations on the specified task, as in
the following example:
     <pre class="smallexample">          (gdb) info tasks
            ID       TID P-ID Pri State                  Name
             1   8077880    0  15 Child Activation Wait  main_task
          *  2   807c468    1  15 Runnable               task_1
          (gdb) info task 2
          Ada Task: 0x807c468
          Name: task_1
          Thread: 0x807f378
          Parent: 1 (main_task)
          Base Priority: 15
          State: Runnable
</pre>
     <br><dt><code>task</code><dd><a name="index-task_0040r_007b-_0028Ada_0029_007d-871"></a><a name="index-current-Ada-task-ID-872"></a>This command prints the ID of the current task.

     <pre class="smallexample">          (gdb) info tasks
            ID       TID P-ID Pri State                  Name
             1   8077870    0  15 Child Activation Wait  main_task
          *  2   807c458    1  15 Runnable               t
          (gdb) task
          [Current task is 2]
</pre>
     <br><dt><code>task </code><var>taskno</var><dd><a name="index-Ada-task-switching-873"></a>This command is like the <code>thread </code><var>threadno</var>
command (see <a href="Threads.html#Threads">Threads</a>).  It switches the context of debugging
from the current task to the given task.

     <pre class="smallexample">          (gdb) info tasks
            ID       TID P-ID Pri State                  Name
             1   8077870    0  15 Child Activation Wait  main_task
          *  2   807c458    1  15 Runnable               t
          (gdb) task 1
          [Switching to task 1]
          #0  0x8067726 in pthread_cond_wait ()
          (gdb) bt
          #0  0x8067726 in pthread_cond_wait ()
          #1  0x8056714 in system.os_interface.pthread_cond_wait ()
          #2  0x805cb63 in system.task_primitives.operations.sleep ()
          #3  0x806153e in system.tasking.stages.activate_tasks ()
          #4  0x804aacc in un () at un.adb:5
</pre>
     <br><dt><code>break </code><var>linespec</var><code> task </code><var>taskno</var><dt><code>break </code><var>linespec</var><code> task </code><var>taskno</var><code> if ...</code><dd><a name="index-breakpoints-and-tasks_002c-in-Ada-874"></a><a name="index-task-breakpoints_002c-in-Ada-875"></a><a name="index-break-_0040dots_007b_007d-task-_0040var_007btaskno_007d_0040r_007b-_0028Ada_0029_007d-876"></a>These commands are like the <code>break ... thread ...</code>
command (see <a href="Thread-Stops.html#Thread-Stops">Thread Stops</a>). 
<var>linespec</var> specifies source lines, as described
in <a href="Specify-Location.html#Specify-Location">Specify Location</a>.

     <p>Use the qualifier &lsquo;<samp><span class="samp">task </span><var>taskno</var></samp>&rsquo; with a breakpoint command
to specify that you only want <span class="sc">gdb</span> to stop the program when a
particular Ada task reaches this breakpoint.  <var>taskno</var> is one of the
numeric task identifiers assigned by <span class="sc">gdb</span>, shown in the first
column of the &lsquo;<samp><span class="samp">info tasks</span></samp>&rsquo; display.

     <p>If you do not specify &lsquo;<samp><span class="samp">task </span><var>taskno</var></samp>&rsquo; when you set a
breakpoint, the breakpoint applies to <em>all</em> tasks of your
program.

     <p>You can use the <code>task</code> qualifier on conditional breakpoints as
well; in this case, place &lsquo;<samp><span class="samp">task </span><var>taskno</var></samp>&rsquo; before the
breakpoint condition (before the <code>if</code>).

     <p>For example,

     <pre class="smallexample">          (gdb) info tasks
            ID       TID P-ID Pri State                 Name
             1 140022020   0   15 Child Activation Wait main_task
             2 140045060   1   15 Accept/Select Wait    t2
             3 140044840   1   15 Runnable              t1
          *  4 140056040   1   15 Runnable              t3
          (gdb) b 15 task 2
          Breakpoint 5 at 0x120044cb0: file test_task_debug.adb, line 15.
          (gdb) cont
          Continuing.
          task # 1 running
          task # 2 running
          
          Breakpoint 5, test_task_debug () at test_task_debug.adb:15
          15               flush;
          (gdb) info tasks
            ID       TID P-ID Pri State                 Name
             1 140022020   0   15 Child Activation Wait main_task
          *  2 140045060   1   15 Runnable              t2
             3 140044840   1   15 Runnable              t1
             4 140056040   1   15 Delay Sleep           t3
</pre>
     </dl>

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