I ran into numerous problems when trying to compile bandwidthd 2.0.1 on OpenBSD 4.3. The first problem was that, even though I had installed all the dependencies via ports, ./configure was still erroring out with:
checking for png_read_info in -lpng... no configure: error: Bandwidthd requires but cannot libpng
Hunting around the web, I managed to get past that error, but then ran into this:
checking for gdImageCreate in -lgd... no configure: error: Bandwidthd requires but cannot find libgd
The solution to both of these problems is this:
./configure LDFLAGS=-lz -x-libraries=/usr/X11R6/lib
I thought I was good to go at that point, but a make resulted in this problem:
Graph cycles through conf.l.c `all' not remade because of errors.
I banged my head on this for some time before turning to the OpenBSD misc mailing list. Philip Guenther pointed me in the right direction:
The makefile is either buggy or assumes a non-POSIX make. Try it again with ‘gmake’. If you still get errors, yell at the bandwidthd authors.
I grabbed gmake from ports and voilà, success!