The file /var/yp/updaters is a makefile (see make(1S)) which is used for updating the Network Information Service (NIS) databases. Databases can only be updated in a secure network, that is, one that has a publickey(4) database. Each entry in the file is a make target for a particular NIS database. For example, if there is an NIS database named passwd.byname that can be updated, there should be a make target named passwd.byname in the updaters file with the command to update the file.
The information necessary to make the update is passed to the update command through standard input. The information passed is described below (all items are followed by a NEWLINE except for 4 and 6):
Network name of client wishing to make the update (a string).
Kind of update (an integer).
Number of bytes in key (an integer).
Actual bytes of key.
Number of bytes in data (an integer).
Actual bytes of data.
After receiving this information through standard input, the command to update the particular database determines whether the user is allowed to make the change. If not, it exits with the status YPERR_ACCESS. If the user is allowed to make the change, the command makes the change and exits with a status of zero. If there are any errors that may prevent the updaters from making the change, it should exit with the status that matches a valid NIS error code described in <rpcsvc/ypclnt.h>.
The Network Information Service (NIS) was formerly known as Sun Yellow Pages (YP). The functionality of the two remains the same; only the name has changed. The name Yellow Pages is a registered trademark in the United Kingdom of British Telecommunications plc, and may not be used without permission.