Using TotalView Variables

User_Guides : Classic TotalView User Guide : PART II Debugging Tools and Tasks : Evaluating Expressions : Using Built-in Variables and Statements : Using TotalView Variables

TotalView variables that let you access special thread and process values. All variables are 32-bit integers, which is an int or a long on most platforms. The following table describes built-in variables:

Name	Returns
$clid	The cluster ID. (Interpreted expressions only.)
$duid	The TotalView-assigned Debugger Unique ID (DUID). (Interpreted expressions only.)
$newval	The value just assigned to a watched memory location. (Watchpoints only.)
$nid	The node ID. (Interpreted expressions only.)
$oldval	The value that existed in a watched memory location before a new value modified it. (Watchpoints only.)
$pid	The process ID.
$processduid	The DUID (debugger ID) of the process. (Interpreted expressions only.)
$systid	The thread ID assigned by the operating system. When this is referenced from a process, TotalView throws an error.
$tid	The thread ID assigned by TotalView. When this is referenced from a process, TotalView throws an error.

The built-in variables let you create thread-specific breakpoints from the expression system. For example, the $tid variable and the $stop built-in function let you create a thread-specific breakpoint, as the following code shows:

if ($tid == 3)

$stop;

This tells TotalView to stop the process only when the third thread evaluates the expression.

You can also create complex expressions using these variables; for example:

if ($pid != 34 && $tid > 7)

printf (“Hello from %d.%d\n”, $pid, $tid);

Using any of the following variables means that the eval point is interpreted instead of compiled: $clid, $duid, $nid, $processduid, $systid, $tid, and $visualize. In addition, $pid forces interpretation on AIX.

You can’t assign a value to a built-in variable or obtain its address.