Implementing sysctls, Part 1

Example 3-3 is a complete KLD (based on code written by Andrzej Bialecki) that creates multiple sysctls.

Example 3-3. pointless.c

#include <sys/param.h>
  #include <sys/module.h>
  #include <sys/kernel.h>
  #include <sys/systm.h>
  #include <sys/sysctl.h>

  static long  a = 100;
  static int   b = 200;
  static char *c = "Are you suggesting coconuts migrate?";

  static struct sysctl_ctx_list clist;
  static struct sysctl_oid *poid;

  static int
 sysctl_pointless_procedure(SYSCTL_HANDLER_ARGS) { char *buf = "Not at all. They could be carried."; return (sysctl_handle_string(oidp, buf, strlen(buf), req)); } static int pointless_modevent(module_t ...

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