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InterruptHookTrace()

Attach the pseudo interrupt handler that's used by the instrumented module

Synopsis:

#include <sys/neutrino.h>

int InterruptHookTrace( 
   const struct sigevent * (* handler)(int),
   unsigned flags );

Library:

libc

Description:

The InterruptHookTrace() function attaches the pseudo interrupt handler handler which is used by the instrumented module.

Before calling this function, the thread must request I/O privileges by calling:

ThreadCtl( _NTO_TCTL_IO, 0 );

The handler argument specifies the pseudo interrupt handler that receives trace events from the kernel.

The flags argument is a bitwise OR of the following values, or 0:

Flag Description
_NTO_INTR_FLAGS_END Put the new handler at the end of the list of existing handlers (for shared interrupts) instead of the start.

_NTO_INTR_FLAGS_END

The interrupt structure allows trace interrupts to be shared. For example, if two processes take over the same trace interrupt, both handlers are invoked consecutively. When a handler attaches, it's placed in front of any existing handlers for that interrupt and is called first. This behavior can be changed by setting the _NTO_INTR_FLAGS_END flag in the flags argument. This adds the handler at the end of any existing handlers.

Blocking states

This call doesn't block.

Returns:

An interrupt function ID, or -1 if an error occurs (errno is set).

Errors:

EAGAIN
All kernel interrupt entries are in use.
EFAULT
A fault occurred when the kernel tried to access the buffers provided.
EPERM
The process doesn't have superuser capabilities.

Classification:

QNX Neutrino

Safety:
Cancellation point No
Interrupt handler No
Signal handler Yes
Thread Yes

See also:

TraceEvent()