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<== Date ==> <== Thread ==>

Subject: Re: empty channel field in medm/dm2k
From: "Ben-chin K. Cha" <cha@aps.anl.gov>
To: tech-talk@aps.anl.gov, larrieu@jlab.org
Date: Mon, 22 Nov 1999 11:52:12 -0600 (CST)

> 
> > I also use this " " to replace the NULL pvname if the user
> > mistakenly provided a NULL string for name search to an
> > interactive CA client. If I remember it right this will
> > avaoid the problem of core dump and accidentally get
> > out of the interactive CA client.
> 
>   I don't understand: if you're going to test for a zero-
> length string, why even bother making the CA function call 
> with name " " when you know it's going to fail?
> 


Sometimes we do want to have some legal 'NULL' string pvname,
e.g. in montitoring variable number of positioner and
detector pvnames in a scan record. It is intentionally as
a NULL string.

Ben-chin



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