diff options
Diffstat (limited to 'libexec/revnetgroup')
| -rw-r--r-- | libexec/revnetgroup/revnetgroup.8 | 33 |
1 files changed, 22 insertions, 11 deletions
diff --git a/libexec/revnetgroup/revnetgroup.8 b/libexec/revnetgroup/revnetgroup.8 index 18bfa2b..9a6258a 100644 --- a/libexec/revnetgroup/revnetgroup.8 +++ b/libexec/revnetgroup/revnetgroup.8 @@ -50,22 +50,26 @@ utility processes the contents of a file in .Xr netgroup 5 format into what is called .Pa reverse netgroup -form. That is, where the original file shows +form. +That is, where the original file shows netgroup memberships in terms of which members reside in a particular group, the reverse netgroup format specifies what groups are associated -with a particular member. This information is used to generate the +with a particular member. +This information is used to generate the .Pa netgroup.byuser and .Pa netgroup.byhosts .Tn NIS -maps. These reverse netgroup maps are used to help speed up +maps. +These reverse netgroup maps are used to help speed up netgroup lookups, particularly for the .Fn innetgr library function. .Pp For example, the standard .Pa /etc/netgroup -file may list a netgroup and a list of its members. Here, the +file may list a netgroup and a list of its members. +Here, the netgroup is considered the .Em key and the member names are the @@ -74,7 +78,8 @@ By contrast, the reverse .Pa netgroup.byusers database lists each unique member as the key and the netgroups to which the members belong become -the data. Separate databases are created to hold information pertaining +the data. +Separate databases are created to hold information pertaining to users and hosts; this allows netgroup username lookups and netgroup hostname lookups to be performed using independent keyspaces. .Pp @@ -83,13 +88,15 @@ By constructing these reverse netgroup databases (and the corresponding maps) in advance, the .Xr getnetgrent 3 library functions are spared from having to work out the dependencies -themselves on the fly. This is important on networks with large numbers +themselves on the fly. +This is important on networks with large numbers of users and hosts, since it can take a considerable amount of time to process very large netgroup databases. .Pp The .Nm -utility prints its results on the standard output. It is usually called +utility prints its results on the standard output. +It is usually called only by .Pa /var/yp/Makefile when rebuilding the @@ -109,7 +116,8 @@ original netgroup file is processed. Generate .Pa netgroup.byhost output; only hostname information in the -original netgroup file is processed. (Note at least one of the +original netgroup file is processed. +(Note at least one of the .Fl u or .Fl h @@ -119,9 +127,11 @@ The .Nm utility uses .Pa /etc/netgroup -as its default input file. The +as its default input file. +The .Fl f -flag allows the user to specify an alternate input file. Specifying ``-'' +flag allows the user to specify an alternate input file. +Specifying ``-'' as the input file causes .Nm to read from the standard input. @@ -137,7 +147,8 @@ to build the .Tn NIS databases .It Pa /etc/netgroup -the default netgroup database file. This file is most often found +the default netgroup database file. +This file is most often found only on the .Tn NIS master server |
