# Look for functions in $list. Return as soon as the first function is found,
# defining has_$fun
for fun in $list; do
  if ($CC $CFLAGS has_$fun.c -o $exe $extra_flags > /dev/null 2>&1); then
    if test  -s $exe -a -x $exe ; then
      eval "has_$fun=yes"; echo ..."Found $fun."
      case "$_has_list" in
        *has_$fun*);;
        *) _has_list="$_has_list has_$fun";;
      esac
      break
    fi
  fi;
  eval "has_$fun=no"; echo ..."I did not find $fun."
done
rm -f $exe
