xref: /freebsd/lib/libc/gen/getgrouplist.3 (revision f126890a)
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28.Dd October 26, 2014
29.Dt GETGROUPLIST 3
30.Os
31.Sh NAME
32.Nm getgrouplist
33.Nd calculate group access list
34.Sh LIBRARY
35.Lb libc
36.Sh SYNOPSIS
37.In unistd.h
38.Ft int
39.Fn getgrouplist "const char *name" "gid_t basegid" "gid_t *groups" "int *ngroups"
40.Sh DESCRIPTION
41The
42.Fn getgrouplist
43function reads through the group file and calculates
44the group access list for the user specified in
45.Fa name .
46The
47.Fa basegid
48is automatically included in the groups list.
49Typically this value is given as
50the group number from the password file.
51.Pp
52The resulting group list is returned in the array pointed to by
53.Fa groups .
54The caller specifies the size of the
55.Fa groups
56array in the integer pointed to by
57.Fa ngroups ;
58the actual number of groups found is returned in
59.Fa ngroups .
60.Sh RETURN VALUES
61The
62.Fn getgrouplist
63function
64returns 0 on success and \-1 if the size of the group list is too small to
65hold all the user's groups.
66Here, the group array will be filled with as many groups as will fit.
67.Sh FILES
68.Bl -tag -width /etc/group -compact
69.It Pa /etc/group
70group membership list
71.El
72.Sh SEE ALSO
73.Xr setgroups 2 ,
74.Xr initgroups 3
75.Sh HISTORY
76The
77.Fn getgrouplist
78function first appeared in
79.Bx 4.4 .
80