more getcpu

userland/linux/getcpu.c

@@ -14,7 +14,7 @@
 /* man getcpu says this exists since glibc 2.29, but I can't find it in Ubuntu 20.04 glibc 2.31 not even with locate
  * (there is a hit under /usr/src/linux-headers-5.4.0-29/include/linux/getcpu.h but it only defines `struct getcpu_cache`
  * and nothing else:
- * https://stackoverflow.com/questions/23224607/how-do-i-include-linux-header-files-like-linux-getcpu-h
+ * https://stackoverflow.com/questions/23224607/how-do-i-include-linux-header-files-like-linux-getcpu-h/61774312#61774312
  * Furthermore, there is already a prototype in sched.h, so we can't define our own either. */
 #if 0
 #include <linux/getcpu.h>
@@ -23,7 +23,7 @@
 void* main_thread(void *arg) {
     (void)arg;
     unsigned cpu, numa;
-    getcpu(&cpu, &numa);
+    assert(!getcpu(&cpu, &numa));
     printf("%u %u\n", cpu, numa);
     return NULL;
 }