Add a file that I forgot in the last commit; Also update some comments.

include/syslog.h

@@ -137,8 +137,60 @@ extern "C"
 {
 #endif
 
+/****************************************************************************
+ * Name: openlog
+ *
+ * Description:
+ *   The openlog() function sets process attributes that affect subsequent
+ *   calls to syslog(). The ident argument is a string that is prepended to
+ *   every message. The logopt argument indicates logging options. Values
+ *   for logopt are constructed by a bitwise-inclusive OR of zero or more of
+ *   the following:
+ *
+ *     LOG_PID - Log the process ID with each message. This is useful for
+ *       identifying specific processes.
+ *
+ *     LOG_CONS - Write messages to the system console if they cannot be
+ *       sent to the logging facility. The syslog() function ensures that
+ *       the process does not acquire the console as a controlling terminal
+ *       in the process of writing the message.
+ *
+ *     LOG_NDELAY - Open the connection to the logging facility immediately.
+ *       Normally the open is delayed until the first message is logged.
+ *       This is useful for programs that need to manage the order in which
+ *       file descriptors are allocated.
+ *
+ *     LOG_ODELAY - Delay open until syslog() is called.
+ *
+ *     LOG_NOWAIT - Do not wait for child processes that may have been
+ *       created during the course of logging the message. This option
+ *       should be used by processes that enable notification of child
+ *       termination using SIGCHLD, since syslog() may otherwise block
+ *       waiting for a child whose exit status has already been collected.
+ *
+ *   The facility argument encodes a default facility to be assigned to all
+ *   messages that do not have an explicit facility already encoded. The
+ *   initial default facility is LOG_USER.
+ *
+ *   It is not necessary to call openlog() prior to calling syslog().
+ *
+ ****************************************************************************/
+
 #if 0 /* Not supported */
 void openlog(FAR const char *ident, int option, int facility);
+#endif
+
+/****************************************************************************
+ * Name: closelog
+ *
+ * Description:
+ *   The openlog() and syslog() functions may allocate a file descriptor.
+ *   The closelog() function will close any open file descriptors allocated
+ *   by previous calls to openlog() or syslog().
+ *
+ ****************************************************************************/
+
+#if 0 /* Not supported */
 void closelog(void);
 #endif