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[unix-history] / usr / src / lib / libutil / pwcache.3

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.\"     @(#)pwcache.3	5.4 (Berkeley) 4/19/91
.\"
.Dd April 19, 1991
.Dt PWCACHE 3
.Os
.Sh NAME
.Nm pwcache
.Nd cache password and group entries
.Sh SYNOPSIS
.Fn user_from_uid "uid_t uid" "int nouser"
.Fn group_from_gid "gid_t gid" "int nogroup"
.Sh DESCRIPTION
.Bf -symbolic
This interface is not part of the C library.
It has been placed in the Berkeley utility library, libutil, as it is
used by several standard utilities.
.Ef
.Pp
The
.Fn user_from_uid
function returns the user name associated with the argument
.Fa uid .
The user name is cached so that multiple calls with the same
.Fa uid 
do not require additional calls to
.Xr getpwuid 3 .
If there is no user associated with the
.Fa uid ,
a pointer is returned
to an
.Tn ASCII
representation of the
.Fa uid ,
unless the argument
.Fa nouser
is non-zero, in which case a
.Dv NULL
pointer is returned.
.Pp
The
.Fn group_from_gid
function returns the group name associated with the argument
.Fa gid .
The group name is cached so that multiple calls with the same
.Fa gid
do not require additional calls to
.Xr getgrgid 3 .
If there is no group associated with the
.Fa gid ,
a pointer is returned
to an
.Tn ASCII
representation of the
.Fa gid ,
unless the argument
.Fa nogroup
is non-zero, in which case a
.Dv NULL
pointer is returned.
.Sh SEE ALSO
.Xr getgrgid 3 ,
.Xr getpwuid 3
.Sh HISTORY
The
.Fn user_from_id
and
.Fn group_from_id
functions are
.Ud .