Adding a chmod binding.

lib/chibi/filesystem.sld

@@ -33,8 +33,7 @@
           file-lock        file-truncate
           file-is-readable? file-is-writable? file-is-executable?
           lock/shared lock/exclusive lock/non-blocking lock/unlock
-          is-a-tty?)
+          chmod is-a-tty?)
   (import (chibi) (chibi string))
   (include-shared "filesystem")
   (include "filesystem.scm"))
-

lib/chibi/filesystem.stub

@@ -212,6 +212,10 @@
 ;;> Locking operations.
 ;;/
 
+;;> Sets the file permissions as in chmod.
+
+(define-c int chmod (string int))
+
 ;;> Returns \scheme{#t} if the given port of file descriptor
 ;;> if backed by a TTY object, and \scheme{#f} otherwise.