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A sequential access in physical record order is really a series of random
accesses by physical record number. The FPOINT and FREADC
intrinsics are used to read records in order of their physical location in the
file. The FPOINT intrinsic sets the physical record pointer to the
position specified in its record number parameter. The FREADC
intrinsic reads the record specified by the physical record pointer without
reference to the logical record pointer. A subsequent FREADC intrinsic
advances the physical record pointer to the next physical record. Any record
containing a delete flag is ignored and is not read.
The FREADDIR intrinsic also reads files in physical record order. It
positions the pointer to the record specified in the record number parameter.
A subsequent FREADDIR intrinsic call repositions the physical record
pointer to the next physical record. Note that deleted records are not ignored
with this intrinsic. It is recommended, therefore, that you use the
FPOINT and FREADC intrinsics to read records sequentially in
physical record order. Use the FREADDIR intrinsic only to read a
single record identified by its physical record number.
The FGETINFO intrinsic returns the physical record pointer setting, as
well as other information, for the record most recently accessed. This number
is returned in the record pointer parameter and can be used in a subsequent
FPOINT or FREADDIR intrinsic call.
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