1.\" $NetBSD: genassym.1,v 1.5 2010/04/13 09:01:10 jruoho Exp $ 2.\" 3.\" Copyright (c) 1997 Matthias Pfaller. 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.Dd April 13, 2010 27.Dt GENASSYM 1 28.Os 29.Sh NAME 30.Nm genassym 31.Nd emit an assym.h file 32.Sh SYNOPSIS 33.Nm genassym 34.Op Fl c 35.Op Fl f 36.Ar C compiler invocation 37.Sh DESCRIPTION 38.Nm 39is a shell script normally used during the kernel build process to 40create an assym.h file. 41This file defines a number of cpp constants derived from the configuration 42information 43.Nm 44reads from stdin. The generated file is used by kernel sources 45written in assembler to gain access to information (e.g. structure 46offsets and sizes) normally only known to the C compiler. 47.Pp 48Arguments to 49.Nm 50are usually of the form 51.Ar ${CC} ${CFLAGS} ${CPPFLAGS} 52where 53.Ar ${CC} 54is the C compiler used to compile the kernel, while 55.Ar ${CFLAGS} 56and 57.Ar ${CPPFLAGS} 58are flag arguments to the C compiler. The script creates a C source file 59from its input. Then the C compiler is called according to the script's 60arguments to compile this file. 61.Pp 62Normally 63.Nm 64instructs the C compiler to create an assembler source from the constructed 65C source. The resulting file is then processed to extract the information 66needed to create the assym.h file. The 67.Fl c 68flag instructs 69.Nm 70to create slightly different code, generate an executable from this code 71and run it. In both cases the assym.h file is written to stdout. 72The 73.Fl f 74flag instructs 75.Nm 76to create forth code. 77.Sh DIAGNOSTICS 78Either self-explanatory, or generated by one of the programs 79called from the script. 80.Sh SEE ALSO 81.Xr genassym.cf 5 82.Sh HISTORY 83The 84.Nm 85command appeared in 86.Nx 1.3 87as 88.Dq genassym.sh 89in 90.Pa /usr/src/sys/kern . 91It became a userland utility in 92.Nx 4.0 . 93