class IO < Object
Call setvbuf(3) with the given mode and buffer (size is calculated from the length of the buffer).
|mode||one of IO::NBF (non-buffered), IO::FBF (fully-buffered), or IO::LBF (line-buffered). IO::LBF is the default for $stdin/$stdout/$stderr when connected to a tty. On most systens, IO::FBF is the default for $stdin/$stdout/$stderr when not connected to a tty, but this is system-dependant. IO::FBF with a zero-length buffer is the default for all files. The default for all other IO objects is unspecified.|
|buf||The buffer to give to setvbuf. It may be a) a String object whose length is the length of the buffer, or b) nil, to indicate a zero-length buffer.|