--- !ruby/object:RI::MethodDescription aliases: [] block_params: comment: - !ruby/struct:SM::Flow::P body: Provides a mechanism for issuing low-level commands to control or query file-oriented I/O streams. Arguments and results are platform dependent. If arg is a number, its value is passed directly. If it is a string, it is interpreted as a binary sequence of bytes (Array#pack might be a useful way to build this string). On Unix platforms, see fcntl(2) for details. Not implemented on all platforms. full_name: IO#fcntl is_singleton: false name: fcntl params: | ios.fcntl(integer_cmd, arg) => integer visibility: public