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.\" @(#)sync.2 6.3 (Berkeley) 3/10/91
.Nd "synchronize disk block in-core status with that on disk"
function forces a write of dirty (modified) buffers
in the block buffer cache out
to disk. The kernel keeps this information in core to reduce
the number of disk I/O transfers required by the system.
As information in the cache is lost after a system crash a
(about every 30 seconds).
may be used to synchronize individual file descriptor
may return before the buffers are completely flushed.
function call appeared in Version 6 AT&T UNIX.