Boot-time loadable drivers

Configuring BTLDs into the Link Kit at boot time

If link(HW) or ahslink is used to link a BTLD at boot time, these commands perform some of the functions that idconfig(ADM ) and idmkunix(ADM) perform for non-BTLD drivers. A properly-written driver can be installed either at boot time or through the Link Kit with no modifications. If a BTLD includes an ./install/INSTALL script, the btld bootstring can be used to install the contents of a BTLD into the Link Kit during installation. As the contents will be extracted directly into the Link Kit and not installed using custom into a software storage object (SSO), this may cause problems if the installed drivers are subsequently upgraded. We recommend that drivers are not installed at boot-time (though they may be linked into the kernel at this time) under SCO OpenServer 5 Release 5 but that they are installed using custom after the system has been booted.

The system performs the following steps when BTLDs are configured into the Link Kit using the btld bootstring when the system is installed:

  1. The installation program runs to extract all the contents of the BTLD disk(s) onto the hard disk under the /tmp/btld hierarchy. Subdirectories are numbered sequentially (1, 2, 3, and so on) to represent the number of the floppy disk.

  2. The LINK/ccs script invokes the LINK/ script at the PostConfigure phase of custom(ADM). The installation program executes the INSTALL script for each subdirectory in the /tmp/btld directory.

  3. The /install/INSTALL script calls btldinstall(ADM) to verify that the driver(s) can be installed and then installs them. For details of this step, see the btldinstall(ADM) manual page. For a list of the files that should be included, see btld(F) For guidelines about writing these scripts, see ``Guidelines for writing BTLDs''.
Ideally, installation should not require any user interaction after the initial prompts are answered. Vendors who distribute BTLDs should follow the guidelines in ``Guidelines for writing BTLDs'' to ensure that their installation scripts do not require unnecessary user interaction during system installation.
© 2005 The SCO Group, Inc. All rights reserved.