Writing Code Fragments

You can use code fragments in evaluation points and in the Tools > Evaluate dialog box. This section describes the intrinsic variables, built-in statements, and language constructs supported by TotalView.

Intrinsic Variables

The TotalView expression system supports built-in variables that allow you to 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 lists the intrinsic variable names and their meanings.


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 of the process. (Interpreted expressions only.)
$systid	The system-assigned thread ID. When this is referenced from a process, TotalView throws an error.
$tid	The TotalView-assigned thread ID. When this is referenced from a process, TotalView throws an error.

Intrinsic variables allow you to create thread-specific breakpoints from the expression system. For example, the $tid intrinsic variable and the $stop built-in operation let you create thread-specific breakpoint as follows:

This tells TotalView to stop the process only when thread 3 evaluates the expression.

You can also create complex expressions by using intrinsic variables. For example:

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