[To reply replace "Aaron.Sloman.XX" with "A.Sloman"]
This is a problem I get from time to time, and I know at least
two others who do. Although it happens rarely, it can be
disastrous when it happens.
The context is this:
You are editing a file XXX
You ask Ved to open a file YYY
e.g. via a program that uses the Pop-11 procedure edit
or by an explicit "ENTER ved YYY" command
or by a procedure that involves veddo with an edit
command string.
etc.
Then you find that the file YYY has indeed been read in, but has
replaced the contents of the buffer file XXX. So if XXX was
recently changed and not written work is lost.
Because of this I have taken to using ved_autosave with a very
short interval.
I have experienced this in Poplog V15.52 and V15.53. I can't
recall whether it existed in eariler versions. I think it occurs
on both Sparc/Solaris poplog and Dec Alpha Unix poplog.
(a) Does anyone have any idea what could be causing this problem
or
(b) How to fix it?
(c) Is this peculiar to Birmingham or has it been experienced
anywhere else?
We use a non-standard version of startup.psv with various things
pre-compiled, including objectclass, rc_graphic and various
graphical utilities providng menus for driving Ved. But the
problem occurs even when these are not being used.
It may have something to do with ved_lockfile, used here to
enable files to be "locked" when read into Ved, to prevent
duplicate editing. See
http://www.cs.bham.ac.uk/research/poplog/help/ved_lockfile
http://www.cs.bham.ac.uk/research/poplog/lib/ved_lockfile.p
But I can't see anything in there that could cause a newly read
in file to replace the buffer of the current file.
The fact that it happens only rarely, but when it happens it is
after a commonly used command, suggests that the bug is context
dependent in some subtle way. Maybe there's a timing issue?
My main work-around at present is to use a short time interval
for ved_autosave, so that if a file is replaced in this way,
little work is lost. (We have a local version with more options
than the standard ved_autosave.)
Aaron
===
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Aaron Sloman, ( http://www.cs.bham.ac.uk/~axs/ )
School of Computer Science, The University of Birmingham, B15 2TT, UK
EMAIL A.Sloman AT cs.bham.ac.uk (NB: Anti Spam address)
TOOLS: http://www.cs.bham.ac.uk/research/poplog/freepoplog.html
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