Re: reread doesn't

[sfeam <sf...@us...>]

On Tuesday, 29 September 2015 12:04:04 PM pl...@pi... wrote:
> Hi
> 
> I am producing a graph ( SVG ) by using load command.
> 
> To refresh it periodically, I have a pause and a reread at the end.

You can only have one plot in an svg output file, "refresh it" is
not an option.  You would have to close it, reopen another file
with the same name, and write a new plot into it.
Is that what your script does?

"reread" only resets the input file, not the output file.
It is possible you misunderstand where the "reload" command
needs to go.  Is there an "unset output" before it?


> The problem is the reread does NOT reread the file. I seems to have an 
> internal buffer and just pretends to reread.

Not sure who you mean by "I".
If you mean gnuplot, then no.
But if you mean the operating system, then probably yes.
Gnuplot's "reread" command tells the system to go back to the
beginning of the file.  That is a "rewind" operation, not a
"close and re-open for reading" operation.

> I can not find anything that would force an actual reread of the file.
> 
> It would be extremely useful if it did really reread the file on disk 
> since this would allow another process to modify it.

No, sorry.  File systems don't work that way.  If somebody else
writes on top of a file you already have open for reading, that 
is probably not going to do what you seem to expect.

 > I seem to recall that there was some complication with this same 
> functionality needing to support pipes or direct input.
> 
> Is there not a way to force a actual reload of the file? Maybe a ' 
> reread really ' option.


	Ethan