Table of Contents
maps
the shared memory segment associated with the shared memory identifier
into the address space of the calling process. The address at which the
segment is mapped is determined by the parameter. If it is equal to 0,
the system will pick an address itself. Otherwise, an attempt is made to
map the shared memory segment at the address specifies. If SHM_RND is set
in the system will round the address down to a multiple of SHMLBA bytes
(SHMLBA is defined in ).
A shared memory segment can be mapped read-only
by specifying the SHM_RDONLY flag in
unmaps the shared memory segment
that is currently mapped at from the calling process’ address space. must
be a value returned by a prior call. A shared memory segment will remain
existant until it is removed by a call to with the IPC_RMID command.
returns the address at which the shared memory segment has been
mapped into the calling process’ address space when successful, returns
0 on successful completion. Otherwise, a value of -1 is returned, and the
global variable is set to indicate the error.
will fail if: The
calling process has no permission to access this shared memory segment.
There is not enough available data space for the calling process to map
the shared memory segment. is not a valid shared memory identifier.
specifies
an illegal address. The number of shared memory segments has reached the
system-wide limit.
will fail if: is not the start address of a mapped
shared memory segment.
Table of Contents