Sorry if this is a duplicate. I tried posting via the web interface, but it
seems to have just deleted what I wrote without posting.

The pkgsrc/sysutils/s5ipc package is a qnx-specific System V IPC
implementation - or as pkg_info says: Library and QNX Resource Manager to
support SysV ipc - The package implement the sysv ipc(shm, sem, msg) on
QNX6. It includes headers, lib and a resmgr. shm.h etc. It's packaged by
(and perhaps also written by) Sean.

Lots of other packages depend on s5ipc.

It uses a lot of build system magic. The build system is x86-specific. I
got it to build on arm for arm by doing a lot of ugly things. A lot of
symlinks outside the pkgsrc dir. Renaming directories and small edits to
files in the pkgsrc dir.

I am interested in learning about pkgsrc, but if anyone could easily make
the build not architecture specific, or just has comments on it in general,
that'd be great. I'm not even sure the magic is all coming from pkgsrc.

Thanks,
-Danny