Clarify that "unused" fields in seminfo structure are

"unused within the kernel".
Minor rewordings in comments for seminfo structure.

man2/semctl.2

@@ -36,7 +36,7 @@
 .\"	Added semid_ds and ipc_perm structure definitions
 .\" 2005-08-02, mtk: Added IPC_INFO, SEM_INFO, SEM_STAT descriptions.
 .\"
-.TH SEMCTL 2 2004-11-10 "Linux" "Linux Programmer's Manual"
+.TH SEMCTL 2 2008-05-20 "Linux" "Linux Programmer's Manual"
 .SH NAME
 semctl \- semaphore control operations
 .SH SYNOPSIS
@@ -180,18 +180,20 @@ feature test macro is defined:
 .in +4n
 
 struct  seminfo {
-    int semmap;  /* # of entries in semaphore map;
-                    unused */
-    int semmni;  /* Max. # of semaphore sets */
-    int semmns;  /* Max. # of semaphores in all
+    int semmap;  /* Number of entries in semaphore
+                    map; unused within kernel */
+    int semmni;  /* Maximum number of semaphore sets */
+    int semmns;  /* Maximum number of semaphores in all
                     semaphore sets */
-    int semmnu;  /* System-wide max. # of undo
-                    structures; unused */
-    int semmsl;  /* Max. # of semaphores in a set */
-    int semopm;  /* Max. # of operations for semop(2) */
-    int semume;  /* Max. # of undo entries per
-                    process; unused */
-    int semusz;  /* size of struct sem_undo */
+    int semmnu;  /* System-wide maximum number of undo
+                    structures; unused within kernel */
+    int semmsl;  /* Maximum number of semaphores in a
+                    set */
+    int semopm;  /* Maximum number of operations for
+                    semop(2) */
+    int semume;  /* Maximum number of undo entries per
+                    process; unused within kernel */
+    int semusz;  /* Size of struct sem_undo */
     int semvmx;  /* Maximum semaphore value */
     int semaem;  /* Max. value that can be recorded for
                     semaphore adjustment (SEM_UNDO) */