SCO has kernel parameter issues with semphores. SHMMAX parameter by default is small. This is a known issue. Here is SCO docset for installing Postgres that discusses it.

Managing Kernel Resources

There are directions for viewing the SHMMAX setting . If it is default, consider raising the value and see if it resolves the shared memory problems you are having.

Otheus -

you are correct - times() uses struct tms not utimes(). That was my bad.