Insert a user string trace event, using a variable argument list
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.
Note:
You can't use any floating-point formatting codes or parameters; use a function such as
sprintf()
to format floating-point data in a temporary buffer, and then pass it to
trace_vnlogf()
using a
%s format.
- 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:
The number of bytes written in the log, including the terminating null character, or -1 if 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 |
Yes |
| Signal handler |
Yes |
| Thread |
Yes |