For uuuusssseeeerrrrttttiiiimmmmeeee, ttttoooottttaaaallllttttiiiimmmmeeee, ****____hhhhwwwwccccttttiiiimmmmeeee, iiiioooo, and ffffppppeeee experiments on
applications that use pthreads (on Irix 6.5 or later), analyze data
only for the specified pthreads. This flag is ignored for other