Q: Why is IRAF complaining that os.zgtenv: cannot open `/usr/include/iraf.h'?

Most likely, you did not set the imdir variable in your login.cl as instructed.

Do so. Then, in each directory where you have data files exhibiting this problem, type:

	imcopy *.imh *.imh

Credit: This answer was provided by Catherine Cress and Toby Rider.