xref: /freebsd/lib/libc/gen/getgrouplist.3 (revision cbb3ec25236ba72f91cbdf23f8b78b9d1af0cedf)
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28.\"     @(#)getgrouplist.3	8.1 (Berkeley) 6/9/93
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30.Dd October 26, 2014
31.Dt GETGROUPLIST 3
32.Os
33.Sh NAME
34.Nm getgrouplist
35.Nd calculate group access list
36.Sh LIBRARY
37.Lb libc
38.Sh SYNOPSIS
39.In unistd.h
40.Ft int
41.Fn getgrouplist "const char *name" "gid_t basegid" "gid_t *groups" "int *ngroups"
42.Sh DESCRIPTION
43The
44.Fn getgrouplist
45function reads through the group file and calculates
46the group access list for the user specified in
47.Fa name .
48The
49.Fa basegid
50is automatically included in the groups list.
51Typically this value is given as
52the group number from the password file.
53.Pp
54The resulting group list is returned in the array pointed to by
55.Fa groups .
56The caller specifies the size of the
57.Fa groups
58array in the integer pointed to by
59.Fa ngroups ;
60the actual number of groups found is returned in
61.Fa ngroups .
62.Sh RETURN VALUES
63The
64.Fn getgrouplist
65function
66returns 0 on success and \-1 if the size of the group list is too small to
67hold all the user's groups.
68Here, the group array will be filled with as many groups as will fit.
69.Sh FILES
70.Bl -tag -width /etc/group -compact
71.It Pa /etc/group
72group membership list
73.El
74.Sh SEE ALSO
75.Xr setgroups 2 ,
76.Xr initgroups 3
77.Sh HISTORY
78The
79.Fn getgrouplist
80function first appeared in
81.Bx 4.4 .
82