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.\"     @(#)initgroups.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
.\"
.Dd June 4, 1993
.Dt INITGROUPS 3
.Os
.Sh NAME
.Nm initgroups
.Nd initialize group access list
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In unistd.h
.Ft int
.Fn initgroups "const char *name" "gid_t basegid"
.Sh DESCRIPTION
The
.Fn initgroups
function
uses the
.Xr getgrouplist 3
function to calculate the group access list for the user
specified in
.Fa name .
This group list is then setup for the current process using
.Xr setgroups 2 .
The
.Fa basegid
is automatically included in the groups list.
Typically this value is given as
the group number from the password file.
.Sh RETURN VALUES
.Rv -std initgroups
.Sh ERRORS
The
.Fn initgroups
function may fail and set
.Va errno
for any of the errors specified for the library function
.Xr setgroups 2 .
It may also return:
.Bl -tag -width Er
.It Bq Er ENOMEM
The
.Fn initgroups
function was unable to allocate temporary storage.
.El
.Sh SEE ALSO
.Xr setgroups 2 ,
.Xr getgrouplist 3
.Sh HISTORY
The
.Fn initgroups
function appeared in
.Bx 4.2 .
.Sh BUGS
The
.Fn getgrouplist
function called by
.Fn initgroups
uses the routines based on
.Xr getgrent 3 .
If the invoking program uses any of these routines,
the group structure will
be overwritten in the call to
.Fn initgroups .