Event Specification Modifiers

An event specification modifier sets additional attributes of a handler, the most common kind being event filters. Modifiers have to appear after the keyword portion of an event spec. They all begin with a dash (-), preceded by blanks. Modifiers consist of the following:

-if cond

The condition is evaluated when the event specified by the event-spec occurs. The side effect of the handler is allowed only if the condition evaluates to nonzero.

If -if is used with an event that has an associated singular source location, such as in or at, cond is evaluated in the scope corresponding to that location, otherwise it should be properly qualified with the desired scope.

-in func

The handler is active only while within the given function, or any function called from func. The number of times the function is entered is reference counted so as to properly deal with recursion.

-disable

Create the handler in the disabled state.

-count n-count infinity

Have the handler count from 0. Each time the event occurs, the count is incremented until it reaches n. Once that happens, the handler fires and the counter is reset to zero.

Counts of all enabled handlers are reset when a program is run or rerun. More specifically, they are reset when the sync event occurs.

-temp

Create a temporary handler. Once the event is fired it is automatically deleted. By default, handlers are not temporary. If the handler is a counting handler, it is automatically deleted only when the count reaches 0 (zero).

Use the delete -temp command to delete all temporary handlers.

-instr

Makes the handler act at an instruction level. This replaces the traditional 'i' suffix of most commands. It usually modifies two aspects of the event handler.

• Any message prints assembly level rather than source level information.

• The granularity of the event becomes instruction level. For instance, step -instr implies instruction level stepping.

-thread tid

The event is executed only if the thread that caused it matches tid.

-lwp lid

The event is executed only if the thread that caused it matches lid.

-hidden

Makes the handler not show up in a regular status command. Use status -h to see hidden handlers.

-perm

Normally all handlers get thrown away when a new program is loaded. Using this modifier causes the handler to be retained across debuggings. A plain delete command will not delete a permanent handler. Use delete -p to delete a permanent handler.