1.\" 2.\" Copyright 2002 Massachusetts Institute of Technology 3.\" 4.\" Permission to use, copy, modify, and distribute this software and 5.\" its documentation for any purpose and without fee is hereby 6.\" granted, provided that both the above copyright notice and this 7.\" permission notice appear in all copies, that both the above 8.\" copyright notice and this permission notice appear in all 9.\" supporting documentation, and that the name of M.I.T. not be used 10.\" in advertising or publicity pertaining to distribution of the 11.\" software without specific, written prior permission. M.I.T. makes 12.\" no representations about the suitability of this software for any 13.\" purpose. It is provided "as is" without express or implied 14.\" warranty. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 17.\" ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 18.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 19.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 20.\" SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22.\" LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 23.\" USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24.\" ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 25.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 26.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27.\" SUCH DAMAGE. 28.\" 29.\" $FreeBSD$ 30.\" 31.Dd October 27, 2002 32.Dt CHECK_UTILITY_COMPAT 3 33.Os 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