link error

[Yixun Liu]

Hi,
I compile petsc successfully, but when I run a simple petsc example,
some errors appear. It seems that I miss x11 lib.

/home/scratch/yixun/petsc-3.0.0-p3/linux-gnu-c-debug/lib/libpetsc.a(xops.o):
In function `PetscDrawLine_X':
/home/scratch/yixun/petsc-3.0.0-p3/src/sys/draw/impls/x/xops.c:29:
undefined reference to `XSetForeground'
/home/scratch/yixun/petsc-3.0.0-p3/src/sys/draw/impls/x/xops.c:32:
undefined reference to `XDrawLine'
/home/scratch/yixun/petsc-3.0.0-p3/linux-gnu-c-debug/lib/libpetsc.a(xops.o):
In function `PetscDrawPoint_X':
/home/scratch/yixun/petsc-3.0.0-p3/src/sys/draw/impls/x/xops.c:45:
undefined reference to `XSetForeground'
/home/scratch/yixun/petsc-3.0.0-p3/src/sys/draw/impls/x/xops.c:46:
undefined reference to `XDrawPoint'


Thanks.