NAME
sync
—
synchronize disk block in-core status
with that on disk
SYNOPSIS
#include
<unistd.h>
void
sync
(void);
DESCRIPTION
The
sync
()
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 sync
() call is
issued frequently by the in-kernel process update (about every 30
seconds).
The function fsync(2) may be used to synchronize individual file descriptor attributes.
SEE ALSO
HISTORY
A sync
() function call appeared in
Version 2 AT&T UNIX.
BUGS
sync
() may return before the buffers are
completely flushed.