Line problems

If I draw a 2d shape using lines is there a command that can be used to fill in the area enclosed by the lines?

Also how do I change the thickness of my lines?

Thanks
Simbad

[PanzerSchreck]

Since OpenGL is a 3D-API there's no concept of filling a 2D-Area.But if you use GL_POLYGON instead of GL_LINES to draw your shape,then it'll be filled.
And for the linewidth : glLineWidth should do the job. (Note that different GL-Implementations offer you different max. linewidths)