OpenSSL BIO_f_buffer(3openssl)
NNNNAAAAMMMMEEEEBIO_f_buffer - buffering BIO
SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS#include
BIO_METHOD * BIO_f_buffer(void);
#define BIO_get_buffer_num_lines(b) BIO_ctrl(b,BIO_C_GET_BUFF_NUM_LINES,0,NULL)
#define BIO_set_read_buffer_size(b,size) BIO_int_ctrl(b,BIO_C_SET_BUFF_SIZE,size,0)
#define BIO_set_write_buffer_size(b,size) BIO_int_ctrl(b,BIO_C_SET_BUFF_SIZE,size,1)
#define BIO_set_buffer_size(b,size) BIO_ctrl(b,BIO_C_SET_BUFF_SIZE,size,NULL)
#define BIO_set_buffer_read_data(b,buf,num) BIO_ctrl(b,BIO_C_SET_BUFF_READ_DATA,num,buf)
DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNNBIO_f_buffer() returns the buffering BIO method.
Data written to a buffering BIO is buffered and periodically written to the next BIO in the chain. Data read from a buffering BIO comes from an internal buffer which is filledfrom the next BIO in the chain. Both BIO_gets() and
BIO_puts() are supported.
Calling BIO_reset() on a buffering BIO clears any buffered
data.BIO_get_buffer_num_lines() returns the number of lines
currently buffered.BIO_set_read_buffer_size(), BIO_set_write_buffer_size() and
BIO_set_buffer_size() set the read, write or both read and
write buffer sizes to ssssiiiizzzzeeee. The initial buffer size isDEFAULT_BUFFER_SIZE, currently 4096. Any attempt to reduce
the buffer size below DEFAULT_BUFFER_SIZE is ignored. Any
buffered data is cleared when the buffer is resized.BIO_set_buffer_read_data() clears the read buffer and fills
it with nnnnuuuummmm bytes of bbbbuuuuffff. If nnnnuuuummmm is larger than the current buffer size the buffer is expanded. NNNNOOOOTTTTEEEESSSSBuffering BIOs implement BIO_gets() by using BIO_read()
operations on the next BIO in the chain. By prepending a buffering BIO to a chain it is therefore possible to provideBIO_gets() functionality if the following BIOs do not
support it (for example SSL BIOs). Data is only written to the next BIO in the chain when thewrite buffer fills or when BIO_flush() is called. It is
therefore important to call BIO_flush() whenever any pending
data should be written such as when removing a buffering BIO3/May/2010 Last change: 0.9.8o 1
OpenSSL BIO_f_buffer(3openssl)
using BIO_pop(). BIO_flush() may need to be retried if the
ultimate source/sink BIO is non blocking. RRRREEEETTTTUUUURRRRNNNN VVVVAAAALLLLUUUUEEEESSSSBIO_f_buffer() returns the buffering BIO method.
BIO_get_buffer_num_lines() returns the number of lines
buffered (may be 0).BIO_set_read_buffer_size(), BIO_set_write_buffer_size() and
BIO_set_buffer_size() return 1 if the buffer was
successfully resized or 0 for failure.BIO_set_buffer_read_data() returns 1 if the data was set
correctly or 0 if there was an error. SSSSEEEEEEEE AAAALLLLSSSSOOOOBIO(3), BIO_reset(3), BIO_flush(3), BIO_pop(3), BIO_ctrl(3),
BIO_int_ctrl(3)
3/May/2010 Last change: 0.9.8o 2