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From: Kienan Stewart via lttng-dev <lttng-dev@lists.lttng.org>
To: Norbert Lange <nolange79@gmail.com>,
	lttng-dev <lttng-dev@lists.lttng.org>
Subject: Re: Method to get LTTNG-UST version during runtime?
Date: Mon, 23 Jun 2025 10:21:05 -0400	[thread overview]
Message-ID: <df98623f-172e-4e71-9592-cb864e239000@efficios.com> (raw)
In-Reply-To: <CADYdroMBu0gocZXpeaMWqr3TG4p5FW71eeN1+y-XM_8bDxijzw@mail.gmail.com>

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


  reply	other threads:[~2025-06-23 14:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-06-18 15:22 Norbert Lange via lttng-dev
2025-06-23 14:21 ` Kienan Stewart via lttng-dev [this message]
2025-06-23 19:04   ` Norbert Lange via lttng-dev
2025-06-25 21:15     ` Kienan Stewart via lttng-dev

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