pSOSystem System Calls - Read

pSOS+ System Calls rn_create
Notes
See Also
1. Internally, the pSOS+ kernel treats a region name as a 32-bit integer. However,
when the application calls the kernel through the pSOS+ C language API, it
passes the region name as a four-byte character array.
2. The pSOS+ kernel does not check for duplicate region names. If duplicate
names exist, an rn_ident() call can return the rnid of any region with the
duplicate name.
3. A region must consist of physically contiguous memory locations.
4. The maximum input length for a region is 32767 times the region's unit size. A
length that exceeds this limit for a given unit size is treated as an error, the
remedy for which is a bigger unit size.
5. When the RN_DEL attribute is specified, a region can be deleted while segments
are outstanding; otherwise, the pSOS+ kernel requires all segments to be
returned before the region can be deleted.
Multiprocessor Considerations
Regions are strictly local resources, and cannot be exported. Therefore, any
allocation calls must come only from the local node. However, if a region's memory
is reachable from other nodes, then any segments allocated from it can be passed
between nodes for direct access explicitly by the user's code.
Callable From
■ Task
rn_ident, rn_getseg
pSOSystem System Calls 1-109
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