TotalView Users Guide - CI Wiki

Using Built-in Variables and Statements
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.
Using Built-In Statements
TotalView statements help you control your interactions in certain circumstances.
These statements are available in all languages, and are described
in the following table. The most commonly used statements are $count,
$stop, and $visualize.
Statement Use
$count expression
$countprocess expression
Sets a process-level countdown breakpoint.
When any thread in a process executes this
statement for the number of times specified by
expression, the process stops. The other processes in
the control group continue to execute.
$countall expression Sets a program-group-level countdown breakpoint.
All processes in the control group stop when any
process in the group executes this statement for the
number of times specified by expression.
$countthread expression Sets a thread-level countdown breakpoint.
When any thread in a process executes this
statement for the number of times specified by
expression, the thread stops. Other threads in the
process continue to execute.
If the target system cannot stop an individual thread,
this statement performs the same as $countprocess.
A thread evaluates expression when it executes $count
for the first time. This expression must evaluate to a
positive integer. When TotalView first encounters this
variable, it determines a value for expression. TotalView
does not reevaluate until the expression actually
stops the thread. This means that TotalView ignores
changes in the value of expression until it hits the
breakpoint. After the breakpoint occurs, TotalView
reevaluates the expression and sets a new value for
this statement.
The internal counter is stored in the process and
shared by all threads in that process.
TotalView Users Guide: version 8.7 395