pSOSystem System Calls - Read

n_getseg pSOS+ System Calls
rn_getseg Allocates a memory segment to the calling task.
#include
unsigned long rn_getseg(
unsigned long rnid, /* region identifier */
unsigned long size, /* requested size, in bytes */
unsigned long flags, /* segment attributes */
unsigned long timeout, /* timeout in clock ticks */
void **seg_addr /* allocated segment address */
)
Description
Arguments
This system call allocates a memory segment of the specified size from the specified
memory region. An allocated segment's size is always the nearest multiple of the
region's unit size, which is an input argument to the rn_create() call.
If the calling task selects the RN_NOWAIT attribute, then rn_getseg() returns
unconditionally (whether or not allocation was successful). If the calling task elects
the RN_WAIT attribute, and a subsequent request cannot be satisfied, the task is
blocked until either a segment is allocated, or a timeout occurs (if the timeout
attribute is elected).
rnid Specifies the region ID from which the memory segment is allocated.
size Specifies the segment size, in bytes.
flags Specifies the segment’s attributes. The flags argument must
assume one of the following values, defined in .
RN_NOWAIT Don't wait for a segment.
RN_WAIT Wait for a segment.
timeout Specifies the timeout, in units of clock ticks. If timeout is 0 and
flags is set to RN_WAIT, then rn_getseg() will wait forever. The
timeout argument is ignored if RN_NOWAIT is used.
seg_addr Points to the variable where rn_getseg() stores the starting
address of the memory segment.
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