Document the new BIO functions introduced as part of the size_t work

=head1 NOTES

BIO_flush(), because it can write data may return 0 or -1 indicating

that the call should be retried later in a similar manner to BIO_write().

that the call should be retried later in a similar manner to BIO_write_ex().

The BIO_should_retry() call should be used and appropriate action taken

is the call fails.

These functions, other than BIO_f_buffer(), are implemented as macros.

Buffering BIOs implement BIO_gets() by using BIO_read() operations on the

Buffering BIOs implement BIO_gets() by using BIO_read_ex() 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).

for the digest routines EVP_DigestInit(), EVP_DigestUpdate()

and EVP_DigestFinal().

Any data written or read through a digest BIO using BIO_read() and

BIO_write() is digested.

Any data written or read through a digest BIO using BIO_read_ex() and

BIO_write_ex() is digested.

BIO_gets(), if its B<size> parameter is large enough finishes the

digest calculation and returns the digest value. BIO_puts() is

SSL BIOs are exceptional in that if the underlying transport

is non blocking they can still request a retry in exceptional

circumstances. Specifically this will happen if a session

renegotiation takes place during a BIO_read() operation, one

renegotiation takes place during a BIO_read_ex() operation, one

case where this happens is when step up occurs.

The SSL flag SSL_AUTO_RETRY can be

=head1 NAME

BIO_get_new_index,

BIO_meth_new, BIO_meth_free, BIO_meth_get_write, BIO_meth_set_write,

BIO_meth_get_read, BIO_meth_set_read, BIO_meth_get_puts, BIO_meth_set_puts,

BIO_meth_get_gets, BIO_meth_set_gets, BIO_meth_get_ctrl, BIO_meth_set_ctrl,

BIO_meth_get_create, BIO_meth_set_create, BIO_meth_get_destroy,

BIO_meth_set_destroy, BIO_meth_get_callback_ctrl,

BIO_meth_new, BIO_meth_free, BIO_meth_get_read_ex, BIO_meth_set_read_ex,

BIO_meth_get_write_ex, BIO_meth_set_write_ex, BIO_meth_get_write,

BIO_meth_set_write, BIO_meth_get_read, BIO_meth_set_read, BIO_meth_get_puts,

BIO_meth_set_puts, BIO_meth_get_gets, BIO_meth_set_gets, BIO_meth_get_ctrl,

BIO_meth_set_ctrl, BIO_meth_get_create, BIO_meth_set_create,

BIO_meth_get_destroy, BIO_meth_set_destroy, BIO_meth_get_callback_ctrl,

BIO_meth_set_callback_ctrl  - Routines to build up BIO methods

=head1 SYNOPSIS

 int BIO_get_new_index(void);

 BIO_METHOD *BIO_meth_new(int type, const char *name);

 void BIO_meth_free(BIO_METHOD *biom);

 int (*BIO_meth_get_write_ex(BIO_METHOD *biom)) (BIO *, const char *, size_t,

                                                 size_t *);

 int (*BIO_meth_get_write(BIO_METHOD *biom)) (BIO *, const char *, int);

 int BIO_meth_set_write_ex(BIO_METHOD *biom,

                           int (*bwrite) (BIO *, const char *, size_t,

                                          size_t *));

 int BIO_meth_set_write(BIO_METHOD *biom,

                        int (*write) (BIO *, const char *, int));

 int (*BIO_meth_get_read_ex(BIO_METHOD *biom)) (BIO *, char *, size_t,

                                                size_t *);

 int (*BIO_meth_get_read(BIO_METHOD *biom)) (BIO *, char *, int);

 int BIO_meth_set_read_ex(BIO_METHOD *biom,

                          int (*bread) (BIO *, char *, size_t, size_t *));

 int BIO_meth_set_read(BIO_METHOD *biom,

                       int (*read) (BIO *, char *, int));

 int (*BIO_meth_get_puts(BIO_METHOD *biom)) (BIO *, const char *);

BIO_meth_free() destroys a B<BIO_METHOD> structure and frees up any memory

associated with it.

BIO_meth_get_write() and BIO_meth_set_write() get and set the function used for

writing arbitrary length data to the BIO respectively. This function will be

called in response to the application calling BIO_write(). The parameters for

the function have the same meaning as for BIO_write().

BIO_meth_get_read() and BIO_meth_set_read() get and set the function used for

reading arbitrary length data from the BIO respectively. This function will be

called in response to the application calling BIO_read(). The parameters for the

function have the same meaning as for BIO_read().

BIO_meth_get_write_ex() and BIO_meth_set_write_ex() get and set the function

used for writing arbitrary length data to the BIO respectively. This function

will be called in response to the application calling BIO_write_ex() or

BIO_write(). The parameters for the function have the same meaning as for

BIO_write_ex(). Older code may call BIO_meth_get_write() and

BIO_meth_set_write() instead. Applications should not call both

BIO_meth_set_write_ex() and BIO_meth_set_write() or call BIO_meth_get_write()

when the function was set with BIO_meth_set_write_ex().

BIO_meth_get_read_ex() and BIO_meth_set_read_ex() get and set the function used

for reading arbitrary length data from the BIO respectively. This function will

be called in response to the application calling BIO_read_ex() or BIO_read().

The parameters for the function have the same meaning as for BIO_read_ex().

Older code may call BIO_meth_get_read() and BIO_meth_set_read() instead.

Applications should not call both BIO_meth_set_read_ex() and BIO_meth_set_read()

or call BIO_meth_get_read() when the function was set with

BIO_meth_set_read_ex().

BIO_meth_get_puts() and BIO_meth_set_puts() get and set the function used for

writing a NULL terminated string to the BIO respectively. This function will be

=head1 SEE ALSO

L<bio>, L<BIO_find_type>, L<BIO_ctrl>, L<BIO_read>, L<BIO_new>

L<bio>, L<BIO_find_type>, L<BIO_ctrl>, L<BIO_read_ex>, L<BIO_new>

=head1 HISTORY