Writing Device Drivers
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Driver Packaging

The normal delivery vehicle for software is to create a package that contains all of the software components. A package provides a controlled mechanism for installation and removal of all the components of a software product. In addition to the files for using the product, the package includes control files for installing and uninstalling the application. The postinstall and preremove installation scripts are two such control files.

Package Postinstall

After a package with a driver binary is installed onto a system, the add_drv(1M) command must be run. The add_drv command completes the installation of the driver. Typically, add_drv is run in a postinstall script, as in the following example.

#!/bin/sh
#
#       @(#)postinstall 1.1

PATH="/usr/bin:/usr/sbin:${PATH}"
export PATH

#
# Driver info
#
DRV=<driver-name>
DRVALIAS="<company-name>,<driver-name>"
DRVPERM='* 0666 root sys'

ADD_DRV=/usr/sbin/add_drv

#
# Select the correct add_drv options to execute.
# add_drv touches /reconfigure to cause the
# next boot to be a reconfigure boot.
#
if [ "${BASEDIR}" = "/" ]; then
    #
    # On a running system, modify the
    # system files and attach the driver
    #
    ADD_DRV_FLAGS=""
else     
    #
    # On a client, modify the system files
    # relative to BASEDIR
    #
    ADD_DRV_FLAGS="-b ${BASEDIR}"
fi       
 
#
# Make sure add_drv has not been previously executed
# before attempting to add the driver.
#
grep "^${DRV} " $BASEDIR/etc/name_to_major > /dev/null 2>&1
if [ $? -ne 0 ]; then
    ${ADD_DRV} ${ADD_DRV_FLAGS} -m "${DRVPERM}" -i "${DRVALIAS}" ${DRV}
    if [ $? -ne 0 ]; then
        echo "postinstall: add_drv $DRV failed\n" >&2
        exit 1
    fi
fi
exit 0

Package Preremove

When removing a package that includes a driver, the rem_drv(1M) command must be run prior to removing the driver binary and other components. The following example demonstrates a preremove script that uses the rem_drv command for driver removal.

#!/bin/sh
#
#       @(#)preremove  1.1
 
PATH="/usr/bin:/usr/sbin:${PATH}"
export PATH
 
#
# Driver info
#
DRV=<driver-name>
REM_DRV=/usr/sbin/rem_drv
 
#
# Select the correct rem_drv options to execute.
# rem_drv touches /reconfigure to cause the
# next boot to be a reconfigure boot.
#
if [ "${BASEDIR}" = "/" ]; then
    #
    # On a running system, modify the
    # system files and remove the driver
    #
    REM_DRV_FLAGS=""
else     
    #
    # On a client, modify the system files
    # relative to BASEDIR
    #
    REM_DRV_FLAGS="-b ${BASEDIR}"
fi
 
${REM_DRV} ${REM_DRV_FLAGS} ${DRV}
 
exit 0
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