diff -r 31fa205db85a -r 1b7716b156a4 configure
--- a/configure	Sat Jul 04 12:28:16 2026 +0200
+++ b/configure	Sun Jul 05 12:26:02 2026 +0200
@@ -89,6 +89,41 @@
         echo
         echo "Configuration:"
     fi
+if true \
+      ; then
+    :
+    if [ -z "$prefix__described__" ] ; then
+        prefix__described__=1
+        cat << '__EOF__'
+  --prefix                path prefix for architecture-independent files [/usr]
+__EOF__
+    fi
+    if [ -z "$exec_prefix__described__" ] ; then
+        exec_prefix__described__=1
+        cat << '__EOF__'
+  --exec-prefix           path prefix for architecture-dependent files [PREFIX]
+__EOF__
+    fi
+    if [ -z "$bindir__described__" ] ; then
+        bindir__described__=1
+        cat << '__EOF__'
+  --bindir                user executables [EPREFIX/bin]
+__EOF__
+    fi
+    if [ -z "$datarootdir__described__" ] ; then
+        datarootdir__described__=1
+        cat << '__EOF__'
+  --datarootdir           read-only architecture-independent data root 
+                          [PREFIX/share]
+__EOF__
+    fi
+    if [ -z "$mandir__described__" ] ; then
+        mandir__described__=1
+        cat << '__EOF__'
+  --mandir                man documentation [DATAROOTDIR/man]
+__EOF__
+    fi
+fi
     cat << '__EOF__'
 
 Build Types:
@@ -114,6 +149,35 @@
 
 # config variables
 has_overridable_config_vars__=0
+if true \
+      ; then
+    :
+    if [ -z "$prefix__initialized__" ] ; then
+        has_overridable_config_vars__=1
+        prefix__initialized__=1
+        prefix='/usr'
+    fi
+    if [ -z "$exec_prefix__initialized__" ] ; then
+        has_overridable_config_vars__=1
+        exec_prefix__initialized__=1
+        exec_prefix=''
+    fi
+    if [ -z "$bindir__initialized__" ] ; then
+        has_overridable_config_vars__=1
+        bindir__initialized__=1
+        bindir=''
+    fi
+    if [ -z "$datarootdir__initialized__" ] ; then
+        has_overridable_config_vars__=1
+        datarootdir__initialized__=1
+        datarootdir=''
+    fi
+    if [ -z "$mandir__initialized__" ] ; then
+        has_overridable_config_vars__=1
+        mandir__initialized__=1
+        mandir=''
+    fi
+fi
 
 # features
 
@@ -124,6 +188,11 @@
 for ARG in "$@"
 do
     case "$ARG" in
+        "--prefix="*) prefix=${ARG#--prefix=} ;;
+        "--exec-prefix="*) exec_prefix=${ARG#--exec-prefix=} ;;
+        "--bindir="*) bindir=${ARG#--bindir=} ;;
+        "--datarootdir="*) datarootdir=${ARG#--datarootdir=} ;;
+        "--mandir="*) mandir=${ARG#--mandir=} ;;
         "--help"*) printhelp ;;
         "--debug") BUILD_TYPE="debug" ;;
         "--release") BUILD_TYPE="release" ;;
@@ -228,6 +297,11 @@
 
 # generate vars.mk
 echo '# configuration' > "$TEMP_DIR/vars.mk"
+echo "prefix=$prefix" >> "$TEMP_DIR/vars.mk"
+echo "exec_prefix=$exec_prefix" >> "$TEMP_DIR/vars.mk"
+echo "bindir=$bindir" >> "$TEMP_DIR/vars.mk"
+echo "datarootdir=$datarootdir" >> "$TEMP_DIR/vars.mk"
+echo "mandir=$mandir" >> "$TEMP_DIR/vars.mk"
 echo >> "$TEMP_DIR/vars.mk"
 
 #
@@ -361,6 +435,26 @@
 if [ $has_overridable_config_vars__ -eq 1 ]; then
     echo
     echo "Config:"
+    if [ -n "$prefix__initialized__" ]; then
+        printf '  %-16s' 'prefix:'
+        echo "$prefix"
+    fi
+    if [ -n "$exec_prefix__initialized__" ]; then
+        printf '  %-16s' 'exec-prefix:'
+        echo "$exec_prefix"
+    fi
+    if [ -n "$bindir__initialized__" ]; then
+        printf '  %-16s' 'bindir:'
+        echo "$bindir"
+    fi
+    if [ -n "$datarootdir__initialized__" ]; then
+        printf '  %-16s' 'datarootdir:'
+        echo "$datarootdir"
+    fi
+    if [ -n "$mandir__initialized__" ]; then
+        printf '  %-16s' 'mandir:'
+        echo "$mandir"
+    fi
 fi
 echo