Choose 'Use prepacked repository catalogues' default option, Accept the EULA, use C:\MinGW as the install folder (do not use a path with spaces in it!)
Click Next - Next until you get to the 'Select Components' menu - now you need to also tick the bottom two options - MSYS Basic System and MinGW Developer Toolkit as well as C Compiler
Wait for the files to be downloaded and installed.
In the Start Menu - run All Programs - MinGW - MinGW Shell
You should now be at a MINGW32 command shell. Type ls to see the files and folders that are present. The actual root folder is located at C:\MinGW\msys\1.0\home\USERNAME (where USERNAME is your Windows user name).
where grubnew will be the name of your new folder containing the latest source files. Note that if you connect via an internet proxy this won't work!
(optional - only do this if you have difficulties or the new grldr file does not load a menu.lst when it boots) To configure the files for the new build (create make files, etc.), type
cd ./grubnew ./configure --enable-preset-menu=preset_menu.lst
If all goes well there will not be any error messages.
Now to compile grub4dos, simply type cd ./grubnew (if not already in the correct directory) make
Again no error messages should be displayed and there should now be a file called grldr in the C:\MinGW\msys\1.0\home\USERNAME\grubnew\grub4dos-temp\grub4dos-0.4.5c folder
Note: If Windows MinGW tops with a 'cannot link at address 2000' error you need to use gcc version 4.5.2-1 as in step 9. If the grldr builds but does not load a menu.lst, you need to add the files detailed in Step 8.
Copy the grldr file to test on your new drive (e.g. you can test the USB drive using RMPrepUSB and the F11 QEMU emulation feature)
Now you can edit the source files as you wish (Notepad may be available) and just type 'make' to remake a new build.
With these three additional utilities installed in step 8, running "make" will build and pack a grub4dos-<version>-<yyyy>-<mm>-<dd>.7z (e.g. grub4dos-0.4.5c-2013-06-10.7z) exactly as found on the grub4dos-chenall download page http://code.google.com/p/grub4dos-chenall/downloads/list.
The 7z archive contains a diff file giving the differences between the locally built file and the svn sources.
If you want to see what you have changed compared to the original source files, open the 7z archive or type svn diff.
To create a new diff file type svn diff > mychanges.diff and then load the file mychanges.diff using NotePad2 or a similar programmers text editor.
Compiling grub4dos utilities - e.g. wenv, echo
1. Download BackTrack 5 ISO and install it to a virtual machine's virtual hard disk (e.g. Windows Virtual PC - set network adapter to Intel 82562V-2 10/100 not NAT). 2. Check the browser is working and then in a console window type svn checkout http://grubutils.googlecode.com/svn%20grubu 3. Use cd to change to the grubutils trunk/src folder and type ./build to build all utilities (all .c files will be compiled add placed in the bin subfolder ). 4. In the Windows Virtual PC Settings menu, enable the Integration features and then in BT5, run Setup from the CD that should now be detected by linux. This will install integration features via WINE. 5. In Dolphin, click on Network and Add Network Folder, enter the name of your host computer - e.g. MyDell\c$, enter the username and password and tick Remember password - if the password does not seem to work - just keep hitting OK until it is accepted - it seems to take several attempts! 6. You should now be able to browse to the host computer C: drive (Applications - Wine - Browse C: drive) and drop any compiled utilities (under the root folder) from the virtual machine onto the host machine.
Now just edit a source file - e.g. wenv.c and type ./build to recompile it. Then copy it to your host C: drive and then copy it to a USB drive to test it (e.g. under QEMU).
2. cd to new folder and run configure --disable-guest-agent (otherwise asks for python) (if error about glib-2.0 required to compile QEMU then edit configure file around line 1840 to comment out exit 1 line)
(if error about error: zlib check failed then install zlib and maybe xy too - see here for instructions) make strip qemu-img.exe (to get rid of debug code)
Note: qemu may not be usable as usually needs tweaks .