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30.Dd $Mdocdate: June 5 2013 $
31.Dt GETGROUPLIST 3
32.Os
33.Sh NAME
34.Nm getgrouplist
35.Nd calculate group access list
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
44.Xr group 5
45file and calculates the group access list for the user specified in
46.Fa name .
47The
48.Fa basegid
49is automatically included in the groups list.
50Typically this value is given as
51the group number from the password file.
52.Pp
53If YP is active and the group file contains no exclusions, the
54.Xr netid 5
55file and the
56.Pa netid.byname
57YP map will be used in addition to the group file.
58If the group file contains at least one exclusion, the
59.Pa group.byname
60YP map will be used in addition to the group file.
61.Pp
62The resulting group list is returned in the integer array pointed to by
63.Fa groups .
64The caller specifies the size of the
65.Fa groups
66array in the integer pointed to by
67.Fa ngroups ;
68the actual number of groups found is returned in
69.Fa ngroups .
70.Sh RETURN VALUES
71The
72.Fn getgrouplist
73function returns 0 if successful and \-1 if the size of the group list is
74too small to hold all the user's groups.
75Here, the group array will be filled with as many groups as will fit.
76.Sh FILES
77.Bl -tag -width /etc/group -compact
78.It Pa /etc/group
79group database file
80.It Pa /etc/netid
81static group lists to override YP data
82.El
83.Sh SEE ALSO
84.Xr setgroups 2 ,
85.Xr initgroups 3 ,
86.Xr yp_match 3 ,
87.Xr group 5 ,
88.Xr netid 5 ,
89.Xr yp 8
90.Sh HISTORY
91The
92.Fn getgrouplist
93function first appeared in
94.Bx 4.4 .
95.Sh BUGS
96The
97.Fn getgrouplist
98function uses the routines based on
99.Xr getgrent 3 .
100If the invoking program uses any of these routines,
101the group structure will be overwritten in the call to
102.Fn getgrouplist .
103