https://community.hpe.com/t5/operating-system-hp-ux/ipcs-m-output-question/m-p/3273565#M884971 That is exactly what that means. It is intended to be used by a process and its descendent processes but this is not an absolute requirement as it can be created with whatever permissions are desired so that other processes with proper permissions can be allowed to access the shmid.<BR /><BR />Man shmget for details.<BR /> Tue, 11 May 2004 14:53:29 GMT A. Clay Stephenson 2004-05-11T14:53:29Z https://community.hpe.com/t5/operating-system-hp-ux/ipcs-m-output-question/m-p/3273564#M884970 We have several systems here and I notice on most of them shared memory segments have key values that are non-zero. There are several however that have a key value of 0x00000000 and I cannot attach to them with a shmget call. Are these zero key value segments marked as IPC_PRIVATE and so new connections cannot be made to them or is there some other significance to the 0x00000000 key value? Tue, 11 May 2004 14:40:42 GMT https://community.hpe.com/t5/operating-system-hp-ux/ipcs-m-output-question/m-p/3273564#M884970 Gordon_10 2004-05-11T14:40:42Z https://community.hpe.com/t5/operating-system-hp-ux/ipcs-m-output-question/m-p/3273565#M884971 That is exactly what that means. It is intended to be used by a process and its descendent processes but this is not an absolute requirement as it can be created with whatever permissions are desired so that other processes with proper permissions can be allowed to access the shmid.<BR /><BR />Man shmget for details.<BR /> Tue, 11 May 2004 14:53:29 GMT https://community.hpe.com/t5/operating-system-hp-ux/ipcs-m-output-question/m-p/3273565#M884971 A. Clay Stephenson 2004-05-11T14:53:29Z