pSOSystem System Calls - Read

pSOS+ System Calls pt_sgetbuf
pt_sgetbuf Gets a buffer from a partition.
#include
unsigned long pt_sgetbuf(
unsigned long ptid, /* partition identifier */
void **paddr, /* physical address */
void **laddr /* logical address */
)
Description
Arguments
Return Value
This system call gets a buffer from a partition. If the partition is empty, an error is
returned.
On MMU-based systems, both physical and logical addresses are returned to
simplify transfer of buffers between supervisor and user mode programs. In non-
MMU systems, the logical address is the same as the physical address, and this call
functions the same as the pt_getbuf() call.
This service is available in the non-MMU versions of the pSOS+ kernel for the sole
purpose of enabling software designed for MMU-based systems to run, unmodified,
on systems without MMU.
ptid Specifies the buffer's partition ID.
paddr Points to the variable where pt_sgetbuf() stores the physical
address of the buffer.
laddr Points to the variable where pt_sgetbuf() stores the logical address
of the buffer.
This system call returns 0 on success, or an error code on failure.
pSOSystem System Calls 1-59
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