From owner-freebsd-hackers@freebsd.org  Wed Mar 30 11:44:19 2016
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Subject: Re: Getting a thread name
To: Sergey Kandaurov <pluknet@gmail.com>
References: <56FBAD69.908@digiware.nl>
 <CAE-mSO+3HMm_mthwGLPiLzmRfxaF2dViHfPzWusAjqd=8TMUHw@mail.gmail.com>
Cc: FreeBSD Hackers <freebsd-hackers@freebsd.org>
From: Willem Jan Withagen <wjw@digiware.nl>
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Date: Wed, 30 Mar 2016 13:44:00 +0200
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On 30-3-2016 13:35, Sergey Kandaurov wrote:
> On 30 March 2016 at 13:41, Willem Jan Withagen <wjw@digiware.nl> wrote:
>> Hi,
>>
>> pthread_np has a call: pthread_set_name(tid, str).
>>
>> Now I'm looking for a way of retrieving that name. But there is no:
>> pthread_get_name() in the same set.
>>
>> But I see top actually displaying the threadnames. So can somebody give
>> me a hint where to look? Other than going thru top...
>>
> 
> It's extracted either over kvm(3) or sysctl(3) interface depending on
> your needs.  Search for kvm_getprocs() and KERN_PROC respectively.
> You can also use libprocstat(3) that is a wrapper.

First 2 sounds rather convoluted....
I have a thread ID and want the string with the threadname back, as set
by pthread_set_name().

Fortunately is the place where I need it atm. is in process wrapup.
So performance is not a real issue.

I'll check your hints, thanx,

--WjW