Stdio.Buffer, need a way to revisit old positions in the output

In perusing the Stdio.Buffer for pgsql NG, I find that I need some way to: a. Fill the output buffer. b. Leave a spot for say a 4 byte integer. c. Fill the output buffer some more. d. Revisit spot (b). e. Write out the newly calculated length. f. Return back to the current tip of the buffer. And

Stdio.Buffer, need a way to revisit old positions in the output

Something along the lines of Buffer sub = b-new_hbuffer(); sub-add... sub-finish(); looks cleaner, I think. -- Per Hedbor