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+=pod
+
+=head1 NAME
+
+BIO_f_buffer - buffering BIO
+
+=head1 SYNOPSIS
+
+ #include <openssl/bio.h>
+
+ 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)
+
+=head1 DESCRIPTION
+
+BIO_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 filled from 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 B<size>. The initial
+buffer size is DEFAULT_BUFFER_SIZE, currently 1024. 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 B<num>
+bytes of B<buf>. If B<num> is larger than the current buffer size the buffer
+is expanded.
+
+=head1 NOTES
+
+Buffering 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 provide BIO_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 the write 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
+BIO using BIO_pop(). BIO_flush() may need to be retried if the ultimate
+source/sink BIO is non blocking.
+
+=head1 RETURN VALUES
+
+BIO_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.
+
+=head1 SEE ALSO
+
+TBA