NAME

update − periodically update the super block

SYNOPSIS

/etc/update

DESCRIPTION

Update is a program that executes the sync(2) primitive every 30 seconds. This insures that the file system is fairly up to date in case of a crash. This command should not be executed directly, but should be executed out of the initialization shell command file.

SEE ALSO

sync(2), sync(1), init(8), rc(8)

WARNINGS

With update running, if the CPU is halted by a hardware reset or power-down just as the sync is being executed, a file system can be damaged.  This should not occur in normal use, as the reboot and halt programs ensure that update has been killed before halting the system. 

7th Edition  —  Revision 1.3 of 10/09/90