hopper script that tags functions which refer to the same global (or static) variable

group.py

doc = Document.getCurrentDocument()
textseg = doc.getSegmentByName('__TEXT')
dataseg = doc.getSegmentByName('__TEXT')

addr = doc.getCurrentAddress()
seg = doc.getSegment(doc.getSegmentIndexAtAddress(addr))
xrefs = seg.getReferencesOfAddress(addr)

doc.log("found {} xrefs to {}".format(len(xrefs), addr))
tagstr = doc.ask("tag to apply? (press cancel for no changes)")

if tagstr:
	tag = doc.buildTag(tagstr)

	for i, x in enumerate(xrefs):
		refseg = doc.getSegment(doc.getSegmentIndexAtAddress(x))
		proc = refseg.getProcedureAtAddress(x)
		if proc:
			proc.addTag(tag)