| | 1 | .\" Copyright (c) 1991, 1993 |
| | 2 | .\" The Regents of the University of California. All rights reserved. |
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| | 10 | .\" notice, this list of conditions and the following disclaimer in the |
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| | 13 | .\" must display the following acknowledgement: |
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| | 15 | .\" California, Berkeley and its contributors. |
| | 16 | .\" 4. Neither the name of the University nor the names of its contributors |
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| | 20 | .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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| | 32 | .\" @(#)update.8 8.3 (Berkeley) 4/19/94 |
| | 33 | .\" |
| | 34 | .Dd April 19, 1994 |
| | 35 | .Dt UPDATE 8 |
| | 36 | .Os |
| | 37 | .Sh NAME |
| | 38 | .Nm update |
| | 39 | .Nd flush internal filesystem caches to disk frequently |
| | 40 | .Sh SYNOPSIS |
| | 41 | .Nm update |
| | 42 | .Op Ar normal_interval Op Ar save_energy_interval |
| | 43 | .Sh DESCRIPTION |
| | 44 | The |
| | 45 | .Nm update |
| | 46 | command helps protect the integrity of disk volumes |
| | 47 | by flushing |
| | 48 | volatile cached filesystem data |
| | 49 | to disk at thirty second intervals. |
| | 50 | .Nm Update |
| | 51 | uses the |
| | 52 | .Xr sync 2 |
| | 53 | function call to do the task. |
| | 54 | The normal_interval and save_energy_interval can be used to set the |
| | 55 | .Xr sync 2 interval in seconds of the normal case and the case where the computer is trying to save energy. |
| | 56 | .Pp |
| | 57 | .Nm Update |
| | 58 | is commonly invoked at startup time by |
| | 59 | .Xr rc 8 |
| | 60 | when the system goes multi-user. |
| | 61 | .Sh SEE ALSO |
| | 62 | .Xr sync 2 , |
| | 63 | .Xr fsck 8 , |
| | 64 | .Xr init 8 , |
| | 65 | .Xr rc 8 , |
| | 66 | .Xr sync 8 |
| | 67 | .Sh BUGS |
| | 68 | It is possible on some systems that a |
| | 69 | .Xr sync |
| | 70 | occurring simultaneously with a crash may cause |
| | 71 | file system damage. See |
| | 72 | .Xr fsck 8 . |
| | 73 | .Sh HISTORY |
| | 74 | An |
| | 75 | .Nm update |
| | 76 | command appeared in |
| | 77 | .At v6 . |
projects / apple / system_cmds.git / blame_incremental