--- !ruby/object:RI::MethodDescription 
aliases: []

block_params: 
comment: 
- !ruby/struct:SM::Flow::P 
  body: Immediately writes all buffered data in <em>ios</em> to disk. Returns <tt>nil</tt> if the underlying operating system does not support <em>fsync(2)</em>. Note that <tt>fsync</tt> differs from using <tt>IO#sync=</tt>. The latter ensures that data is flushed from Ruby's buffers, but doesn't not guarantee that the underlying operating system actually writes it to disk.
full_name: IO#fsync
is_singleton: false
name: fsync
params: |
  ios.fsync   => 0 or nil

visibility: public