Assistance using php_start_ob_buffer

Hi, I'm trying to write an extension that(running under php in fcgi mode) does the equivalent of -php.ini auto_prepend_file = start.inc auto_append_file = end.inc -start.inc ob_start() -end.inc $len = ob_get_length() // modify buffer slightly based on length value // php prints final buffer on script termination So I thought I merely needed to do the C equivalent of these, in short: RINIT php_start_ob_buffer(NULL, 0, 0 TSRMLS_CC); RSHUTDOWN zval * outbuf = NULL; zval outbuflen; INIT_ZVAL(outbuflen); if ( php_ob_get_length(&outbuflen TSRMLS_CC) != FAILURE && Z_L_VAL(outbuflen) != 0 ) { ALLOC_INIT_ZVAL(outbuf); php_ob_get_buffer(outbuf TSRMLS_CC); // Modify buffer based on len parameter } // Done php prints buffer by itself on script return However no matter what variation on the above I've tried, including different php_ob_* api calls I can't ever get any buffer length(I do see script data output). It's like ob_start() was never called. In php.ini I have output_buffering = Off Can someone please point out what I'm missing here? thanks! Dal Eric Len