Here is the procedure I went through to compile xmess on RedHat Linux 7.2 (Enigma).

Usage Instructions (Linux):

1. Download the sources:
   • cd ~
   • TZ=US/Pacific ; # make sure we get the right date
   • today=`date '+%Y%m%d'` ; # should be in the format YYYYMMDD
   • mkdir -p daily/$today
   • cd daily
   • alias leech='wget -c -t 0'
   • leech http://www.mame.net/zips/mame056s.zip ; # MAME 0.56 sources.
   • leech http://x.mame.net/download/xmame-0.56.2.tar.bz2 ; # xmame sources.
   • leech http://homepage.eircom.net/~mess/mess056s.zip ; # MESS sources.
   • leech http://tkmame.retrogames.com/messdaily/mess-patch-$today.bz2 ; # latest patch.
2. Unzip and Patch the sources:
   • unzip mame056s.zip
   • unzip -d $today -L MAME056.ZIP && rm MAME056.ZIP
   • unzip -d $today -L -o mess056s.zip
   • bunzip2 mess-patch-$today.bz2
   • pushd $today
   • patch -p4 < ../mess-patch-$today ; # accept default prompts.
   • popd
3. Port it to unix (you may need to use the porting scripts found in src/unix/contrib/porting/):
   • tar xvjf xmame-0.56.2.tar.bz2
   • pushd xmame-0.56.2/src/unix/contrib/porting
   • gcc -o fix-comments fix-comments.c
   • PATH=$PATH:`pwd`
   • popd
   • fix-comments `find $today -name "*.[ch]"`
   • cp -a xmame-0.56.2/src/unix $today/src
   • cp xmame-0.56.2/makefile.unix $today
4. Modify makefile.unix and compile (at a minimum, modify makefile.unix so that TARGET=mess).
   • cd $today
   • make -f makefile.unix -k TARGET=mess ; # Skip to step 5 if you are running RedHat 7.x
5. RedHat Linux 7.x users will need to compile with:
   • make -f makefile.unix -k TARGET=mess CC=kgcc