xref: /freebsd/lib/libc/gen/check_utility_compat.3 (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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29.Dd October 27, 2002
30.Dt CHECK_UTILITY_COMPAT 3
31.Os
32.Sh NAME
33.Nm check_utility_compat
34.Nd "determine whether a utility should be compatible"
35.Sh LIBRARY
36.Lb libc
37.Sh SYNOPSIS
38.In unistd.h
39.Ft int
40.Fn check_utility_compat "const char *utility"
41.Sh DESCRIPTION
42The
43.Fn check_utility_compat
44function checks whether
45.Fa utility
46should behave in a traditional
47.Pq Fx 4.7 Ns -compatible
48manner, or in accordance with
49.St -p1003.1-2001 .
50The configuration is given as a comma-separated list of utility names;
51if the list is present but empty, all supported utilities assume their
52most compatible mode.
53The
54.Fn check_utility_compat
55function first checks for an environment variable named
56.Ev _COMPAT_FreeBSD_4 .
57If that environment variable does not exist, then
58.Fn check_utility_compat
59will attempt to read the contents of a symbolic link named
60.Pa /etc/compat-FreeBSD-4-util .
61If no configuration is found, compatibility mode is disabled.
62.Sh RETURN VALUES
63The
64.Fn check_utility_compat
65function returns zero if
66.Fa utility
67should implement strict
68.St -p1003.1-2001
69behavior, and nonzero otherwise.
70.Sh FILES
71.Bl -tag -width ".Pa /etc/compat-FreeBSD-4-util"
72.It Pa /etc/compat-FreeBSD-4-util
73If present, a symbolic link whose expansion gives system-wide default settings
74for the
75.Fn check_utility_compat
76function.
77.El
78.Sh ERRORS
79No errors are detected.
80.Sh HISTORY
81The
82.Fn check_utility_compat
83function first appeared in
84.Fx 5.0 .
85.Sh AUTHORS
86This manual page was written by
87.An Garrett Wollman Aq Mt wollman@FreeBSD.org .
88