diff --git a/pkg-def.scm b/pkg-def.scm
index 9e6356d..57226a5 100644
--- a/pkg-def.scm
+++ b/pkg-def.scm
@@ -10,35 +10,38 @@ exec scsh -le ~a/load.scm -o install-lib -e install-main -s "$0" "$@"
 END
 )
 
-(define-package "install-lib" (1 1 0)
-  ((options (bindir "Destination directory for executables" "<dir>" #t #f #f
-                    ,identity ,identity)))
+(define-package "install-lib" (1 1 1)
+  ((options (bindir "Destination directory for executables" "<dir>" #t #f
+                    ,(bin-dir) ,identity ,identity)))
 
+  ;; Install "package" part (doc & Scheme code)
+  (install-file "doc/install-lib.pdf" 'doc "pdf")
+  (install-files '("scheme/install-lib.scm"
+                   "scheme/install-lib-version.scm"
+                   "scheme/install-lib-module.scm")
+                 'scheme)
+  (write-to-load-script
+   `((config)
+     (load ,(absolute-file-name "install-lib-module.scm"
+                                (get-directory 'scheme #f)))
+     (user)))
+
+  ;; Install "program" part (scsh-install-pkg script).
   (let ((bindir (get-option-value 'bindir)))
-    (if (not bindir)
-        (display-error-and-exit
-         "no binary directory specified (use --bindir option)."))
-
-    ;; Install "package" part (doc & Scheme code)
-    (install-file "doc/install-lib.pdf" 'doc "pdf")
-    (install-files '("scheme/install-lib.scm"
-                     "scheme/install-lib-version.scm"
-                     "scheme/install-lib-module.scm")
-                   'scheme)
-    (write-to-load-script
-     `((config)
-       (load ,(absolute-file-name "install-lib-module.scm"
-                                  (get-directory 'scheme #f)))
-       (user)))
-
-    ;; Install "program" part (scsh-install-pkg script).
     (if (or (get-option-value 'dry-run) (get-option-value 'verbose))
         (format #t "creating scsh-install-pkg script in ~a\n" bindir))
 
     (if (not (get-option-value 'dry-run))
-        (begin
-          (create-directory&parents bindir #o755)
-          (call-with-output-file (absolute-file-name "scsh-install-pkg" bindir)
-            (lambda (port)
-              (format port scsh-install-pkg-template (get-directory 'base #f))
-              (set-file-mode port #o755)))))))
+        (let ((wrapper-name (absolute-file-name "scsh-install-pkg" bindir)))
+
+          (with-errno-handler
+           ((errno packet)
+            (else ((display-error-and-exit "cannot create wrapper script "
+                                           wrapper-name ":\n  "
+                                           (first packet)))))
+
+           (create-directory&parents bindir #o755)
+           (call-with-output-file wrapper-name
+             (lambda (port)
+               (format port scsh-install-pkg-template (get-directory 'base #f))
+               (set-file-mode port #o755))))))))