xref: /freebsd/lib/libc/gen/check_utility_compat.3 (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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29.\" $FreeBSD$
30.\"
31.Dd October 27, 2002
32.Os
33.Dt CHECK_UTILITY_COMPAT 3
34.Sh NAME
35.Nm check_utility_compat
36.Nd "determine whether a utility should be compatible"
37.Sh LIBRARY
38.Lb libc
39.Sh SYNOPSIS
40.In unistd.h
41.Ft int
42.Fn check_utility_compat "const char *utility"
43.Sh DESCRIPTION
44The
45.Fn check_utility_compat
46function checks whether
47.Fa utility
48should behave in a traditional
49.Pq Fx 4.7 Ns -compatible
50manner, or in accordance with
51.St -p1003.1-2001 .
52The configuration is given as a comma-separated list of utility names;
53if the list is present but empty, all supported utilities assume their
54most compatible mode.
55The
56.Fn check_utility_compat
57function first checks for an environment variable named
58.Ev _COMPAT_FreeBSD_4 .
59If that environment variable does not exist, then
60.Fn check_utility_compat
61will attempt to read the contents of a symbolic link named
62.Pa /etc/compat-FreeBSD-4-util .
63If no configuration is found, compatibility mode is disabled.
64.Sh RETURN VALUES
65The
66.Fn check_utility_compat
67function returns zero if
68.Fa utility
69should implement strict
70.St -p1003.1-2001
71behavior, and nonzero otherwise.
72.Sh FILES
73.Bl -tag -width ".Pa /etc/compat-FreeBSD-4-util"
74.It Pa /etc/compat-FreeBSD-4-util
75If present, a symbolic link whose expansion gives system-wide default settings
76for the
77.Fn check_utility_compat
78function.
79.El
80.Sh ERRORS
81No errors are detected.
82.Sh HISTORY
83The
84.Fn check_utility_compat
85function first appeared in
86.Fx 5.0 .
87.Sh AUTHORS
88This manual page was written by
89.An Garrett Wollman Aq wollman@FreeBSD.org .
90