How to clean up semaphores

A. Identify all semaphores

ipcs -a

------ Shared Memory Segments --------
key        shmid      owner      perms      bytes      nattch     status     
0x00000000 9043975    yingbin    600        160525768  1          dest        
0x00000000 9306129    yingbin    600        160525768  1          dest        
0x00000000 9076754    yingbin    600        160525768  1          dest        

------ Semaphore Arrays --------
key        semid      owner      perms      nsems    
0x00000000 17924096   yingbin    600        25       
0x00000000 17956865   yingbin    600        25       
0x00000000 17989634   yingbin    600        1        
0x00000000 17137682   yingbin    600        25       
0x00000000 17170451   yingbin    600        25       
0x00000000 17203220   yingbin    600        1        
0x00000000 17235992   yingbin    600        25       
0x00000000 17268761   yingbin    600        25       
0x00000000 17301530   yingbin    600        1        

------ Message Queues --------
key        msqid      owner      perms      used-bytes   messages   

B. Identify the process ID (pid) that are associated with the semaphores

 ipcs -s -i 17301530

Semaphore Array semid=17301530
uid=1005         gid=100         cuid=1005       cgid=100
mode=0600, access_perms=0600
nsems = 1
otime = Mon Apr  7 09:27:24 2014 
ctime = Mon Apr  7 09:27:24 2014 
semnum     value      ncount     zcount     pid      
0                1000              0          0          27036    

C. Find if the process 27036 is still active or has been killed.

ps -ef |grep 27036


D. If the process has been killed, the associated semaphores can be safely cleaned.

ipcrm -s 17301530