# FCM 1.4 Release Notes 12 February 2009

These are the release notes for FCM release 1.4. You can use this release of FCM freely under the terms of the FCM LICENSE, which you should receive with the distribution of this release.

Note that FCM 1.4 requires Subversion 1.4.x (but it has not been tested on Subversion 1.5.x or above).

FCM is maintained by the FCM team at the Met Office. Please feedback any bug reports or feature requests to us by e-mail.

## Minor enhancements & Bug Fixes

Build:

- Fixed: ensure consistent behaviour for specifying `-D`, `-I`, etc options for a preprocessor/compiler.

Code management commands:

- Fixed: `fcm mkpatch`: Fix how property changes are handled.
- Fixed: `fcm mkpatch`: Fix how copied files and directories are handled.
- Fixed: `fcm mkpatch`: Prevent failures caused by the use of Subversion keywords.
- Fixed: `fcm mkpatch`: Prevent failures when used with branches which do not follow the FCM naming convention.

Extract:

- Allow extract config to define an alternate remote shell for `rsync`.

General:

- Some of the example scripts in the `templates/` directory have been rewritten.
- Various other very minor enhancements and bug fixes.

## Known Issues

The following are known issues with this release of FCM which we plan to address in later releases:

- FCM build does not handle changes in an include file correctly in an inherited build if the include file resides in the same directory as the source file including it, and the source file remains unchanged. This is due to the fact that most pre-processor/compiler commands search the directory containing the source file for include files first before they search elsewhere.

## System Requirements

### Perl

The core part of FCM is a set of Perl scripts and modules. For the build system to work, you need the following modules installed:

- Carp
- Cwd
- File::Basename
- File::Compare
- File::Find
- File::Path
- File::Spec::Functions
- File::Spec
- FindBin
- Getopt::Long
- POSIX

The code management commands and extract system need the following additional modules installed:

- File::Temp
- Getopt::Long
- HTTP::Date
- XML::DOM

To use the simple GUI for some of the code management commands, you also need the following modules:

- Tk::ROText
- Tk

At the Met Office we are currently using the complete FCM system with Perl 5.8.x. In addition the build system is being used with Perl 5.6.x.

### Subversion

To use the code management commands (and relevant parts of the extract system) you need to have Subversion installed.

- FCM makes extensive use of peg revisions in both the code management and extract systems. This requires Subversion 1.4.0.
- At the Met Office we are currently using Subversion 1.4.3.

Note that the extract system can mirror extracted code to a remote platform for building. Therefore it is only necessary to have Subversion installed on the platform where you do your code development. If you use other platforms purely for building and running then you do not need to have Subversion installed on these platforms.

### Trac

The use of Trac is entirely optional (although highly recommended if you are using Subversion).

- The `--trac` and `--wiki` options to the `fcm diff --branch` command allow you to view branch differences using Trac. This requires Trac 0.10.
- Some of the example scripts in the `templates/` directory require Trac 0.11.
- At the Met Office we are currently using Trac 0.11.2.1.

### Other Requirements

The `fcm conflicts` command requires xxdiff. At the Met Office we are currently using version 3.1. The `fcm diff --graphical` command also uses xxdiff by default although other graphical diff tools can also be used.

The extract system can use diff3, which is part of GNU diffutils, to merge together changes where the same file is modified by two different branches (compared with the base branch). At the Met Office we are currently using version 2.8.1.

The build system requires GNU make. At the Met Office we are currently using version 3.79.x and 3.80.

Optionally, the build system can use f90aib to generate interface files. However, there is also a built in Perl based interface file generator which is quicker and better in most cases so you are unlikely to need f90aib unless you hit a problem with some particular code.

FCM is intended to run on a Unix/Linux system. It is currently used at the Met Office on Linux (Red Hat Enterprise 2.1 and 4.6) and HP-UX 11.00.

## Installation

FCM is distributed in the form of a compressed tar file. Un-pack the tar file into an appropriate location on your system. Then add the `bin/` directory into your PATH. Once you have done this you should now have full access to the FCM system, assuming that you have met the requirements described in the previous section.

If you wish to define keywords for your systems you will need to create a file `etc/fcm.cfg`. An example file, `fcm.cfg.eg`, is provided which is a copy of the file currently used at the Met Office. For further details please refer to the section FCM keywords in the System Admin chapter of the User Guide.

The `doc/` directory contains all the system documentation.

- `doc/release_notes/` contains these release notes. It also contains the release notes for all previous versions which may be useful if you have skipped any versions.
- `doc/user_guide/` contains the FCM User Guide.
- `doc/design/` contains the FCM Detailed Design document (currently in draft form).
- `doc/standards/` contains the FCM Perl and Fortran coding standards. The Perl standard describes the standards followed by the FCM code. The Fortran standard contains some specific advice on the best way of writing Fortran code for use with FCM as well as more general advice on good practise.
- `doc/collaboration/` contains the External Distribution & Collaboration for FCM Projects document which discusses how projects configured under FCM can be distributed externally.

The `tutorial/` directory contains the files necessary to set up a tutorial repository. This will allow you to follow the tutorial section in the User Guide.

- The file `tutorial/svn.dump` should be loaded into an empty repository using the `svnadmin load` command.
- The hook scripts in `tutorial/hooks/` should then be installed in this repository in order to prevent any commits to the trunk. Note that the configuration file `svnperms.conf` assumes that the tutorial repository is called `tutorial_svn`. Please edit this file if you use a different name.
- The repository should be configured to allow users write access. You may find it easiest to simply allow anonymous access.
- A Trac system should be configured associated with the Tutorial repository. You then need to allow users write access. You may find it easiest to set up a number of guest accounts for this purpose.

The `templates/` directory contains various example scripts which you may find useful. Note that these scripts are all specific to the Met Office and may contain hard coded paths and email addresses. They are provided in the hope that you may find them useful as templates for setting up similar scripts of your own. However, they should only be used after careful review to adapt them to your environment. The contents are as follows:

templates/hooks/pre-commit
  This script restricts write-access to the repository by checking the following:
  - It executes the Subversion utility `svnperms.py` if it, and the associated `svnperms.conf` file, exist. This utility checks whether the author of the current transaction has enough permission to write to particular paths in the repository.
  - It checks the disk space required by the current transaction. It fails the commit if it requires more than 5Mb of disk space.
templates/hooks/post-commit
  A simple post-commit hook script which runs the script `post-commit-background` in the background.
templates/hooks/post-commit-background
  This script runs in the background after each commit
  - It updates a `<repos>.latest` file with the latest revision number.
  - It creates a dump of the new revision.
  - It calls the script `background_updates.pl` if it exists.
  This script is installed as standard in all our repositories.
templates/hooks/background_updates.pl
  An example of how you may want to set up a `background_updates.pl` script to perform post-commit tasks for a specific repository. This script uses a lock file to prevent multiple commits in quick succession from causing problems.
templates/hooks/pre-revprop-change
  A simple pre-revprop-change hook script which runs the script `pre-revprop-change.pl`.
templates/hooks/pre-revprop-change.pl
  If a user attempts to modify the log message of a changeset and he/she is not the original author of the changeset, this script will e-mail the original author. You can also set up a watch facility to monitor changes of log messages that affect particular paths in the repository. For further details please refer to the section Watching changes in log messages in the System Admin chapter of the User Guide.
templates/hooks/post-revprop-change
  A simple post-revprop-change hook script which invokes the `trac-admin` command to `resync` the revision property cache stored in the corresponding Trac environment.
templates/utils/cron_template.sh
  An example of how you might set up a cron job to make use of the `<repos>.latest` file.
templates/utils/FCM/Admin/
  A Perl library in the `FCM::Admin::*` name space, which implements the functionalities of the FCM admin utility commands.
templates/utils/fcm-*
  A selection of useful FCM admin utility commands.