development version does not compile

[John W. Eaton]

On 13-Feb-2009, Bertrand Roessli wrote:

| I had 4.2.3 and installed 4.2.4, but got the same error. 
| I commented out the lines in the m-file and everything compiled
| smoothly.

OK, so if you are using 4.2.4, then you should be seeing

  4.2 patchlevel 4

as the output from the shell command "gnuplot --version", correct?

If so, then I think we've determined that the problem is that the PCRE
library handles the regexp in __gnuplot_version__ correctly, but other
regexp libraries do not.

Do you have the PCRE regexp library installed?  Did configure find it?

Maybe we should change __gnuplot_version__ do the version extraction
without regexp, to avoid this problem.  Additionally, perhaps we
should require PCRE for regexps, so that there is some consistency in
the behavior of Octave's regexp functions.

jwe