[Crash-utility] [PATCH] add a new command: ipcs

[Dave Anderson]

----- Original Message -----
> Hello Dave,
> 
> I have changed the command according to your suggestion. But I
> haven't
> got any SUSE at hand, so the problems with SLES9 may need a bit of
> time
> to get fixed.
> 
> I send the mail together with "ipcs.c" file which hasn't fix the
> problems of SLES9. Later, I will focus on it. Once the problems are
> fixed, I will resend the code again.
> 
   
This is looking pretty good...

A few comments:

This confusion is unnecessary:

 crash> ipcs ffff81042fc7d9d0
 ipcs: specified one of -s -m -M -q together with -i option/addr
 Usage:
   ipcs [-smMq] [-i id | addr]
 Enter "help ipcs" for details.
 crash>

When using a shmid_kernel, msg_queue or sem_array address, why force
the user to also enter -s, -m, -M, or -q?  Those addresses are guaranteed
to be unique values.

And for that matter, you could drop the "-i" entirely.  There may be
duplicate id values among the 3 facilities, but if that's the case,
you could just display all of them.  That way, it could be simplified
to this:

  Usage: ipcs [-smMq] [id | address]

And you could also allow multiple id and/or address values to be entered,
as is done by most of the other crash commands.

And a few other aesthetic issues...

The "------ Shared Memory Segments ------", "------ Semaphore Arrays --------"
and "------ Message Queues --------" lines are unnecessary.  It's obvious
what each section is showing, because the items in the headers self-identify
what facility is being dumped.
 
The semaphore and message queue KEY values still have "0x":
 
 SEM_ARRAY        KEY        SEMID      UID   PERMS NSEMS
 ffff88003de05610 0x00000000 0          0     600   1
 ffff88003775f250 0x00000000 98305      0     600   1
 
 MSG_QUEUE        KEY        MSQID      UID   PERMS USED-BYTES   MESSAGES
 ffff81042fc7d9d0 0x51008003 0          0     700   0            0
 ffff81062f9f0790 0xffffffff 32769      0     600   0            0
 ffff81062fe1d0d0 0x000004d2 98306      0     666   0            0
 
The ipcs -M output could be condensed a bit, from this:
 
 SHMID_KERNEL     KEY      SHMID      UID   PERMS BYTES      NATTCH STATUS
 ffff81062f9f0d90 740004b7 2031616    0     600   4          0      dest
 PAGES ALLOCATED            1
 PAGES RESIDENT             0
 PAGES SWAPPED              1
 SWAP PERFORMANCE ATTEMPTS  0
 SWAP PERFORMANCE SUCCESSES 0
 vfs_inode                  0xffff81062f5ca158
 
to something like this:
 
 SHMID_KERNEL     KEY      SHMID      UID   PERMS BYTES      NATTCH STATUS
 ffff81062f9f0d90 740004b7 2031616    0     600   4          0      dest
  PAGES ALLOCATED: 1 RESIDENT: 0 SWAPPED: 1
  SWAP ATTEMPTS: 0 SUCCESSES: 0
  VFS_INODE: ffff81062f5ca158
 
Other than those few items, I like it...

Thanks,
  Dave