Ruby 1.8.7 リファレンスマニュアル > ライブラリ一覧 > mkmfライブラリ > Kernelモジュール > check_sizeof (private)

instance method Kernel#check_sizeof

check_sizeof(type, headers = nil, &b) [added by mkmf]

Returns the size of the given +type+. You may optionally specify additional +headers+ to search in for the +type+.

If found, a macro is passed as a preprocessor constant to the compiler using the type name, in uppercase, prepended with 'SIZEOF_', followed by the type name, followed by '=X' where 'X' is the actual size.

For example, if check_sizeof('mystruct') returned 12, then the SIZEOF_MYSTRUCT=12 preprocessor macro would be passed to the compiler.