xref: /openbsd-src/lib/libc/gen/getgrouplist.3 (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
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30.Dd $Mdocdate: March 27 2009 $
31.Dt GETGROUPLIST 3
32.Os
33.Sh NAME
34.Nm getgrouplist
35.Nd calculate group access list
36.Sh SYNOPSIS
37.Fd #include <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.
51If YP is active, the
52.Xr netid 5
53file and the
54.Pa netid.byname
55YP map will be used in addition to the group file.
56.Pp
57The resulting group list is returned in the integer array pointed to by
58.Fa groups .
59The caller specifies the size of the
60.Fa groups
61array in the integer pointed to by
62.Fa ngroups ;
63the actual number of groups found is returned in
64.Fa ngroups .
65.Sh RETURN VALUES
66The
67.Fn getgrouplist
68function returns \-1 if the size of the group list is too small to
69hold all the user's groups.
70Here, the group array will be filled with as many groups as will fit.
71.Sh FILES
72.Bl -tag -width /etc/group -compact
73.It Pa /etc/group
74group database file
75.It Pa /etc/netid
76static group lists to override YP data
77.El
78.Sh SEE ALSO
79.Xr setgroups 2 ,
80.Xr initgroups 3 ,
81.Xr yp_match 3 ,
82.Xr group 5 ,
83.Xr netid 5 ,
84.Xr yp 8
85.Sh HISTORY
86The
87.Fn getgrouplist
88function first appeared in
89.Bx 4.4 .
90.Sh BUGS
91The
92.Fn getgrouplist
93function uses the routines based on
94.Xr getgrent 3 .
95If the invoking program uses any of these routines,
96the group structure will be overwritten in the call to
97.Fn getgrouplist .
98