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SYNC(8)                   BSD System Manager's Manual                  SYNC(8)

NAME
     sync -- force completion of pending disk writes (flush cache)

SYNOPSIS
     sync

DESCRIPTION
     Sync can be called to insure that all disk writes have been completed before the processor is halted in
     a way not suitably done by reboot(8) or halt(8).  Generally, it is preferable to use reboot or halt to
     shut down the system, as they may perform additional actions such as resynchronizing the hardware clock
     and flushing internal caches before performing a final sync.

     Sync utilizes the sync(2) function call.

SEE ALSO
     fsync(2), sync(2), halt(8), reboot(8), update(8)

HISTORY
     A sync command appeared in Version 6 AT&T UNIX.

4th Berkeley Distribution        May 31, 1993        4th Berkeley Distribution