mergemaster(8)

NAME

mergemaster - merge configuration files, et al during an up
grade

SYNOPSIS

mergemaster    [-scrvahipCP]   [-m   /path/to/sources]   [-t
/path/to/temp/root]
            [-d] [-u N] [-w N] [-A architecture] [-D /path]

DESCRIPTION

The mergemaster utility is a Bourne shell script which is
designed to aid you in updating the various configuration and other files
associated with
FreeBSD. It is HIGHLY recommended that you back up your
/etc directory before beginning this process.
The script uses /usr/src/etc/Makefile to build a temporary
root environment from / down, populating that environment with the vari
ous files. You can specify a different source directory with the [-m]
command line option, or specify the destination directory with the [-D]
option. It then compares each file in that environment to its installed
counterpart. When the script finds a change in the new file, or there is
no installed version of the new file it gives you four options to deal
with it. You can install the new file as is, delete the new file, merge
the old and new files (as appropriate) using sdiff(1) or leave the file
in the temporary root environment to merge by hand later.
By default it creates the temporary root in
/var/tmp/temproot and compares the cvs(1) version $Id/$FreeBSD strings for files that
have them, deleting the temporary file if the strings match. If there
is no $Id string, or if the strings are different it compares the
files themselves. You can also specify that the script ignore the $Id strings
and compare every file.
The merge menu option is designed to let you easily combine
your customizations from the old version of a file into the new one.
While you can use the merge function to incorporate changes from files
that you have not customized, it is not recommended.
The mergemaster utility checks your umask and issues a warn
ing for anything other than 022. While it is not mandatory to grant
world read permissions for most configuration files, you may run into
problems without them. If you choose a umask other than 022 and experience
trouble later this could be the cause. /etc/master.passwd is treated as a
special case. If you choose to install this file or a merged ver
sion of it the file permissions are always 600 (rw-------) for security
reasons. After installing an updated version of this file you should proba
bly run pwd_mkdb(8) with the -p option to rebuild your password
databases and recreate /etc/passwd.
The script uses the owner and group id's that the files are
created with by /usr/src/etc/Makefile, and file permissions as specified
by the umask. Unified diffs are used by default to display any differences
unless you choose context diffs.
The mergemaster utility will source scripts that you specify
right before it starts the comparison, and after it is done running. The
easiest way to handle this is to place the path to the script(s) in the
appropriate variables in your .mergemasterrc file. The script sourced
before comparison is named in MM_PRE_COMPARE_SCRIPT, and the one sourced
after the script is done is MM_EXIT_SCRIPT. This is the recommended
way to specify local modifications, or files that you want to give special
handling to. This includes files that you want to be deleted without be
ing compared. Because the named scripts are sourced from within
mergemaster, all of the
script's variables are available for use in your custom
script. You can also use /etc/mergemaster.rc which will be read before
.mergemasterrc. Options specified on the command line are updated last, and
therefore can override both files.
The options are as follows:
-s Perform a strict comparison, diff'ing every pair
of files.: This comparison is performed line by line, with; out regard to
CVS $Id's.
-c Use context diffs instead of unified diffs.
-r Re-run mergemaster on a previously cleaned di
rectory, skip: ping the creation of the temporary root environ; ment. This
option is compatible with all other options.
-v Be more verbose about the process. You should
probably use: this option the first time you run mergemaster.; This option
also gives you a list of files that exist only; in the
installed version of /etc.
-a Run automatically. This option will leave all
the files that: differ from the installed versions in the tempo; rary directory
to be dealt with by hand. If the temproot di; rectory exists,
it creates a new one in a previously non-exis; tent directory.
This option unsets the verbose flag, but is com; patible with
all other options. Setting -a makes -w super; fluous.
-h Display usage and help information.
-i Automatically install any files that do not ex
ist in the des: tination directory.
-p Pre-buildworld mode. Compares only files known
to be essen: tial to the success of {build|install}world, in; cluding
/etc/make.conf.
-C After a standard mergemaster run, compares your: rc.conf[.local] options to the defaults.
-P Preserve files that you replace in: /var/tmp/mergemaster/preserved-files-<date>, or; another
directory you specify in your mergemaster rc; file.
-m /path/to/sources: Specify the path to the directory where you want; to do the
make(1). (In other words, where your sources; are, but -s was
already taken.)
-t /path/to/temp/root: Create the temporary root environment in; /path/to/temp/root
instead of the default /var/tmp/temproot.
-d Add the date and time to the name of the tempo
rary root: directory. If -t is specified, this option must; follow it if
you want the date added too.
-u N Specify a numeric umask. The default is 022.
-w N Supply an alternate screen width to the sdiff(1)
command in: numbers of columns. The default is 80.
-A architecture: Specify an alternative TARGET_ARCH architecture; name.
-D /path Specify the destination directory for the in
stalled files.

ENVIRONMENT

The mergemaster utility uses the PAGER environment variable
if set. Otherwise it uses more(1). If PAGER specifies a program out
side its limited
PATH without specifying the full path, mergemaster prompts
you with options on how to proceed. The MM_PRE_COMPARE_SCRIPT and
MM_EXIT_SCRIPT variables are used as described above. Other variables that
are used by the script internally can be specified in .mergemasterrc as
described in more detail below.

FILES

/etc/mergemaster.rc
$HOME/.mergemasterrc

The mergemaster utility will . (source) these files if they
exist. Command line options will override rc file options.
$HOME/.mergemasterrc overrides /etc/mergemaster.rc. Here is an example with all
values commented out:
# These are options for mergemaster, with their default val
ues listed # The following options have command line overrides # # Directory to install the temporary root environment into #TEMPROOT='/var/tmp/temproot' # # Strict comparison bypasses the CVS $Id tests and compares
every file #STRICT=no # # Type of diff, such as unified, context, etc. #DIFF_FLAG='-u' # # Additional options for diff. This will get unset when us
ing -s. #DIFF_OPTIONS='-I$FreeBSD:.*[$]' # Ignores CVS Id
tags # # Verbose mode includes more details and additional checks #VERBOSE= # # Automatically install files that do not exist on the sys
tem already #AUTO_INSTALL= # # Compare /etc/rc.conf[.local] to /etc/defaults/rc.conf #COMP_CONFS=yes # # Preserve files that you replace #PRESERVE_FILES=yes #PRESERVE_FILES_DIR=/var/tmp/mergemaster/preserved
files-`date +%y%m%d-%H%M%S` # # Sourcedir is the directory to do the 'make' in (where the
new files are) #SOURCEDIR='/usr/src/etc' # # The umask for mergemaster to compare the default file's
modes to #NEW_UMASK=022 # # Specify the destination directory for the installed files #DESTDIR= # # The following options have no command line overrides # For those who just cannot stand including the full path to

PAGER

#DONT_CHECK_PAGER=
#
# If you set 'yes' above, make sure to include the PATH to
your pager #PATH=/bin:/usr/bin:/usr/sbin # # Don't compare the old and new motd files #IGNORE_MOTD=yes # # Specify the path to scripts to run before the comparison
starts, # and/or after the script has finished its work #MM_PRE_COMPARE_SCRIPT= #MM_EXIT_SCRIPT=

EXIT STATUS

Exit status is 0 on successful completion, or if the user
bails out manually at some point during execution.
Exit status is 1 if it fails for one of the following rea
sons:
Invalid command line option
Failure to create the temporary root environment
Failure to populate the temporary root

EXAMPLES

Typically all you will need to do is type mergemaster at the
prompt and the script will do all the work for you.
To use context diff's and have mergemaster explain more
things as it goes along, use:: # mergemaster -cv
To specify that mergemaster put the temporary root environ
ment in /usr/tmp/root, use:: # mergemaster -t /usr/tmp/root
To specify a 110 column screen with a strict comparison,
use:: # mergemaster -sw 110

HISTORY

The mergemaster utility was first publicly available on one
of my web pages in a much simpler form under the name comproot on 13
March 1998. The idea for creating the temporary root environment comes
from Nik Clayton's make world tutorial which is referenced above.

AUTHORS

This manual page and the script itself were written by Dou
glas Barton <DougB@FreeBSD.org>.

BUGS

There are no known bugs. Please report any problems, com
ments or suggestions to the author. Several of the improvements to this
program have come from user suggestions. Thank you.
BSD February 4, 2006

docs.sk

comprehensive documentation repository

See also

mergemaster(8)

NAME

SYNOPSIS

DESCRIPTION

ENVIRONMENT

FILES

PAGER

EXIT STATUS

EXAMPLES

SEE ALSO

HISTORY

AUTHORS

BUGS