Trace subroutines for implementing a trace point.
Posix Trace Library (libposixtrace.a)
In the trace stream that calling process is being traced and the event_id is not filtered out, the posix_trace_event subroutine records the values of the event_id parameter and the user data, which is specified by the data_ptr parameter.
The data_len parameter represents the total size of the user trace event data. If the value of the data_len is not larger than the declared maximum size for user trace event data, the truncation-status attribute of the trace event recorded is POSIX_TRACE_NOT_TRUNCATED. Otherwise, the user trace event data is truncated to this declared maximum size and the truncation-status attribute of the trace event recorded is POSIX_TRACE_TRUNCATED_RECORD.
Item | Description |
---|---|
event_id | Specifies the trace event identifier. |
data_ptr | Specifies the user data to be written in the trace streams that the process is tracing in. |
data_len | Specifies the length of the user data to be written. |
No return value is defined for the posix_trace_event subroutine.
This subroutine returns no error code when it fails.