1.\" Copyright (c) 2002 The FreeBSD Project. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.Dd June 13, 2018 26.Dt GETOSRELDATE 3 27.Os 28.Sh NAME 29.Nm getosreldate 30.Nd get the value of 31.Dv __FreeBSD_version 32.Sh LIBRARY 33.Lb libc 34.Sh SYNOPSIS 35.In unistd.h 36.Ft int 37.Fn getosreldate void 38.Sh DESCRIPTION 39The 40.Fn getosreldate 41function returns an integer showing the version of the 42currently running 43.Fx 44kernel. 45Definitions of the values can be found in 46.%B "The Porter's Handbook": 47.Pp 48.Lk https://www.FreeBSD.org/doc/en/books/porters-handbook/ 49.Sh RETURN VALUES 50Upon successful completion, 51.Fn getosreldate 52returns the value requested; 53otherwise the value \-1 is returned and the global variable 54.Va errno 55is set to indicate the error. 56.Sh ENVIRONMENT 57.Bl -tag -width ".Ev OSVERSION" 58.It Ev OSVERSION 59If the environment variable 60.Ev OSVERSION 61is set, it will override the 62.Fn getosreldate 63return value. 64.El 65.Sh EXAMPLES 66An example can be found in 67.Pa /usr/share/examples/FreeBSD_version . 68.Sh ERRORS 69The 70.Fn getosreldate 71function may fail and set 72.Va errno 73for any of the errors specified for the library function 74.Xr sysctl 3 . 75.Sh SEE ALSO 76.Rs 77.%B "The Porter's Handbook" 78.Re 79.Sh HISTORY 80The 81.Fn getosreldate 82function appeared in 83.Fx 2.0 . 84