trace_vnlogf()

Synopsis:

#include <sys/neutrino.h>
#include <sys/trace.h>

int trace_vnlogf( int code,
                  int max,
                  const char *fmt,
                  va_list arglist );

Arguments:

code: The event code, which must be in the range from _NTO_TRACE_USERFIRST through _NTO_TRACE_USERLAST.
max: The maximum length of the string to include in the event, in bytes, or 0 for no limit.
fmt: A printf()-style formatting string.
arglist: A variable argument list of the items required by the fmt string.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The trace_vnlogf() function calls TraceEvent() to insert a user string event of class _NTO_TRACE_USER, and of the type specified by code.

Returns:

0: Success.
-1: An error occurred (errno is set).

Errors:

ECANCELED: The requested action has been canceled.
EFAULT: Bad internal trace buffer address. The requested action has been specified out of order.
ENOMEM: Insufficient memory to allocate the trace buffers.
ENOTSUP: The requested action isn't supported.
EPERM: The application doesn't have permission to perform the action.

Classification:

QNX Neutrino

Safety:
Cancellation point	No
Interrupt handler	Read the Caveats
Signal handler	Yes
Thread	Yes

Caveats:

It isn't safe to call this function from an interrupt handler if the formatting codes or parameters include floating-point elements.