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

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


     The sync utility can be called to ensure that all disk writes have been completed before the processor
     is halted in a way not suitably done by shutdown(8).  Generally, it is preferable to use shutdown(8) 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.

     The sync utility utilizes the sync(2) function call.

     fsync(2), sync(2), shutdown(8)

     A sync utility appeared in Version 4 AT&T UNIX.

BSD                              May 31, 1993                              BSD

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