changeset 2962:08a841b1a567

*** empty log message ***
author Jim Meyering <jim@meyering.net>
date Sun, 05 Nov 2000 10:12:25 +0000
parents 6f34939d48af
children 9f67b35747f9
files lib/tru-knlist-demo.c
diffstat 1 files changed, 51 insertions(+), 22 deletions(-) [+]
line wrap: on
line diff
--- a/lib/tru-knlist-demo.c	Sun Nov 05 09:54:07 2000 +0000
+++ b/lib/tru-knlist-demo.c	Sun Nov 05 10:12:25 2000 +0000
@@ -5,37 +5,66 @@
 #include <string.h>
 #include <stdlib.h>
 #include <nlist.h>
+
+#ifndef FD_CLOEXEC
+# define FD_CLOEXEC 1
+#endif
+
+#ifndef LDAV_SYMBOL
+# define LDAV_SYMBOL "_avenrun"
+#endif
+
+int
 main ()
 {
-  struct nlist   nl[3];
-  int            retval, i;
-  nl[0].n_name = (char *)malloc(10);
-  nl[1].n_name = (char *)malloc(10);
-  nl[2].n_name = "";
+  struct nlist nl[2];
+  int retval;
+  long offset;
 
-  /*******************************************************/
-  /* Store names of kernel symbols in the nl array       */
-  strcpy (nl[0].n_name, "ncpus");
-  strcpy (nl[1].n_name, "lockmode");
+  nl[0].n_name = LDAV_SYMBOL;
+  nl[1].n_name = "";
 
   /*******************************************************/
   /* Call the knlist routine                             */
-  retval = knlist(nl);
+  retval = knlist (nl);
 
   /******************************************************/
   /* Display addresses if returned.  Otherwise, display */
   /* the appropriate error message.                     */
   if (retval < 0)
-     printf ("No kernel symbol addresses returned.\n");
-  else
-     if (retval >= 0 )
-	for (i=0; i<2; i++)
-	    if (nl[i].n_type == 0)
-		printf ("Unable to return address of symbol %s\n",
-			nl[i].n_name);
-	    else
-		printf ("The address of symbol %s is %lx\n",
-			nl[i].n_name, nl[i].n_value);
-  free (nl[0].n_name);
-  free (nl[1].n_name);
+    {
+      printf ("No kernel symbol addresses returned.\n");
+      exit (1);
+    }
+
+  if (nl[0].n_type == 0)
+    {
+      printf ("Unable to return address of symbol %s\n", nl[0].n_name);
+      exit (1);
+    }
+
+  offset = nl[0].n_value;
+  printf ("The address of symbol %s is %lx\n", nl[0].n_name, offset);
+
+  {
+    double load_ave[3];
+    int channel = open ("/dev/kmem", 0);
+    if (channel < 0)
+      {
+	printf ("open failed\n");
+	exit (1);
+      }
+#ifdef FD_SETFD
+    (void) fcntl (channel, F_SETFD, FD_CLOEXEC);
+#endif
+
+    if (lseek (channel, offset, 0) == -1L
+	|| read (channel, (char *) load_ave, sizeof (load_ave))
+	!= sizeof (load_ave))
+      {
+	close (channel);
+      }
+  }
+
+  exit (0);
 }