I have gnuplot 4.6.0 on Windows 7 64 bit Professional.
I have big input file (test.plt in attachment). When it is loaded in wgnuplot, it works OK, charts are shown. But if I feed it as STDIN to pgnuplot:
"C:\Program Files (x86)\gnuplot\bin\pgnuplot.exe" < test.plt
no charts are built, and input in wgnuplot window is corrputed (it seems that some CR are missed).