The sync command runs the sync system primitive. sync writes all unwritten system buffers to disk. This includes modified inodes and delayed block I/O.
Commands that bring the system down, such as the shutdown command, issue their own sync calls. Use the sync command if the system must be stopped under unusual circumstances, to ensure file system integrity.
Note that the writing of unwritten buffers, although scheduled, is not necessarily complete upon return from sync. In some circumstances it may be appropriate to issue consecutive sync commands.
Specifies the command path
Functions: sync(2) delim off