Method to get LTTNG-UST version during runtime?

[Kienan Stewart]

Hi Norbert,

If you link to liblttng-ust-ctl, you can use `lttng_ust_ctl_get_version`.

thanks,
kienan


On 6/18/25 11:22 AM, Norbert Lange via lttng-dev wrote:
> Hi,
> 
> there are some substantial changes in 2.14.0 that afffect how/if
> tracing is possible.
> For ex. c246521ddcba1d1d28cfa0482aa500b9122e7264 allows doing more work upfront
> by calling lttng_ust_init_thread().
> With 2.13.x the same code will instead do various syscalls or
> allocations during the first tracepoints, violating realtime
> constraints and possible abort the process.
> 
> I miss an easy method to inspect the Lttng UST Version for checks or
> workarounds.
> 
> There is the lttng_ust_loaded variable that could be abused to carry
> an packed version instead of 1. (Of course that could always cause
> fallout)
> 
> Regards, Norbert