150 	struct tm t, gm;  in cd9660_compute_gm_offset()  local
153 	(void)gmtime_r(&tim, &gm);  in cd9660_compute_gm_offset()
154 	gm.tm_year -= t.tm_year;  in cd9660_compute_gm_offset()
155 	gm.tm_yday -= t.tm_yday;  in cd9660_compute_gm_offset()
156 	gm.tm_hour -= t.tm_hour;  in cd9660_compute_gm_offset()
157 	gm.tm_min  -= t.tm_min;  in cd9660_compute_gm_offset()
158 	if (gm.tm_year < 0)  in cd9660_compute_gm_offset()
159 		gm.tm_yday = -1;  in cd9660_compute_gm_offset()
160 	else if (gm.tm_year > 0)  in cd9660_compute_gm_offset()
161 		gm.tm_yday = 1;  in cd9660_compute_gm_offset()
163 	return (char)(-(gm.tm_min + 60* (24 * gm.tm_yday + gm.tm_hour)) / 15);  in cd9660_compute_gm_offset()