+=head2 UMASK
+
+Certain calls are affected by the current file mode creation mask (the
+"umask"). In particular ones which create files or directories, such
+as C<guestfs_touch>, C<guestfs_mknod> or C<guestfs_mkdir>. This
+affects either the default mode that the file is created with or
+modifies the mode that you supply.
+
+The default umask is C<022>, so files are created with modes such as
+C<0644> and directories with C<0755>.
+
+There are two ways to avoid being affected by umask. Either set umask
+to 0 (call C<guestfs_umask (g, 0)> early after launching). Or call
+C<guestfs_chmod> after creating each file or directory.
+
+For more information about umask, see L<umask(2)>.
+