build

 #
 # build - compile the Isabelle system and object-logics
 
 if [ -L "$0" ]; then
   TARGET="$(LC_ALL=C ls -l "$0" | sed 's/.* -> //')"
-  exec "$(cd "$(dirname "$0")"; cd "$(dirname "$TARGET")"; pwd)/$(basename "$TARGET")" "$@"
+  exec "$(cd "$(dirname "$0")"; cd "$(pwd -P)"; cd "$(dirname "$TARGET")"; pwd)/$(basename "$TARGET")" "$@"
 fi
 
 
 ## global settings
 
 ALL_LOGICS="Pure FOL HOL ZF CCL CTT Cube FOLP HOLCF LCF Sequents"
 
 
 ## settings
 
+export THIS_IS_ISABELLE_BUILD=true
+
 PRG="$(basename "$0")"
 
-export THIS_IS_ISABELLE_BUILD=true
-
-ISABELLE_HOME="$(dirname "$0")"
-. "$ISABELLE_HOME/lib/scripts/getsettings" || \
-  { echo "$PRG probably not called from its original place!"; exit 2; }
+ISABELLE_HOME="$(cd "$(dirname "$0")"; pwd -P)"
+source "$ISABELLE_HOME/lib/scripts/getsettings" || exit 2
 
 
 ## diagnostics
 
 function usage()