Include errno.h, as RH-9.? and SuSE-8.2, at least, need it.
Include errno.h, as RH-9.? and SuSE-8.2, at least, need it.

svn path=/trunk/; revision=4894

FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot