| sizeof {mmap} | R Documentation |
Calculate the Size of Datatypes
Description
Calculate the number of bytes in an R data type used by mmap.
Usage
sizeof(type)
Arguments
type |
A type constructor (function), R atomic, or mmap |
Details
A constructor for the purposes of sizeof is a function object
used to create an atomic type for R or mmap. These include the
base atomic type functions such as integer, character,
double, numeric, single, complex and
similar. In addition, the Ctype constructors in mmap such
as int8, uint8, real32, etc may be passed in.
More typically a representative object of the above types can be passed in to determine the appropriate data size.
The purpose of this function is for use to help construct a proper
offset argument value for mmap and mprotect, though
neither use is common or encouraged since alignment to pagesize is
required from the system call.
Value
Numeric bytes used.
Author(s)
Jeffrey A. Ryan
See Also
Examples
# all are equal
sizeof(int32)
sizeof(int32())
sizeof(integer)
sizeof(integer())
sizeof(1L)