Apparently the second argument to ap_rgetline serves as an upper bound for the returned line, if the first argument points to NULL. This tripped me up (I expected behaviour like ap_get_brigade(mode=AP_MODE_GETLINE,readbytes=0)), so I thought it deserved mention in the header.
Jim
--- include/http_protocol.h.orig 2003-03-14 00:28:04.000000000 -0800 +++ include/http_protocol.h 2003-03-14 00:29:05.000000000 -0800 @@ -577,7 +577,8 @@ * @param s Pointer to the pointer to the buffer into which the line * should be read; if *s==NULL, a buffer of the necessary size * to hold the data will be allocated from the request pool - * @param n The size of the buffer + * @param n The size of the buffer; if *s==NULL, the maximum size of the + * buffer to be allocated * @param read The length of the line. * @param r The request * @param fold Whether to merge continuation lines
