1# Copyright (c) 1998 Rajesh Vaidheeswarran 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# 3. All advertising materials mentioning features or use of this software 13# must display the following acknowledgement: 14# This product includes software developed by Rajesh Vaidheeswarran 15# 4. The name Rajesh Vaidheeswarran may not be used to endorse or promote 16# products derived from this software without specific prior written 17# permission. 18# 19# THIS SOFTWARE IS PROVIDED BY RAJESH VAIDHEESWARRAN ``AS IS'' AND ANY 20# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22# ARE DISCLAIMED. IN NO EVENT SHALL THE RAJESH VAIDHEESWARRAN BE LIABLE 23# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29# SUCH DAMAGE. 30# 31# Copyright (c) 1993 Terrence R. Lambert. 32# All rights reserved. 33# 34# Redistribution and use in source and binary forms, with or without 35# modification, are permitted provided that the following conditions 36# are met: 37# 1. Redistributions of source code must retain the above copyright 38# notice, this list of conditions and the following disclaimer. 39# 2. Redistributions in binary form must reproduce the above copyright 40# notice, this list of conditions and the following disclaimer in the 41# documentation and/or other materials provided with the distribution. 42# 3. All advertising materials mentioning features or use of this software 43# must display the following acknowledgement: 44# This product includes software developed by Terrence R. Lambert. 45# 4. The name Terrence R. Lambert may not be used to endorse or promote 46# products derived from this software without specific prior written 47# permission. 48# 49# THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``AS IS'' AND ANY 50# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52# ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE 53# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59# SUCH DAMAGE. 60# 61 621.0 Overview 63 64 This is the README file for the sample kld module 65 that mimics a character device driver. 66 67 A kld module may be used to load any data or 68 program into the kernel that can be made available by 69 modifying a table, pointer, or other kernel data to inform 70 the kernel that the module should be used instead of the 71 previous code/data path. 72 73 Generally, it is assumed that a loadable module is one of 74 a set of similar modules (such as a file system or console 75 terminal emulation), and that the reference is through a 76 table (such as vfssw[]), and that a "special" value is 77 assigned to the slots which are allowed to be replaced. 78 This is not enforced, so you may use the kld module 79 any way you see fit. 80 81 As with the loadable system calls, it may be desirable to 82 allow the module loader to replace an *existing* entry to 83 try out changes to kernel code without rebuilding and 84 booting from the new kernel. 85 86 872.0 Directions 88 89 To test the module, do the following: 90 91 cd module 92 make load 93 94 A load message (the copyright) will be printed on the console. 95 96 cd ../test 97 make load 98 99 The system call prints a message on the console when called. 100 This message will be printed when running "make load" in 101 the "test" subdirectory. 102 103 1043.0 Recovering resources 105 106 The module consumes memory when loaded; it can be freed up by 107 unloading it. To unload it, type the following from the directory 108 this file is in: 109 110 cd module 111 make unload 112 113 The miscellaneous module will be unloaded by name. 114 115 1164.0 END OF DOCUMENT 117