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bio(3) [osx man page]

bio(3)								      OpenSSL								    bio(3)

NAME
bio - I/O abstraction SYNOPSIS
#include <openssl/bio.h> TBA DESCRIPTION
A BIO is an I/O abstraction, it hides many of the underlying I/O details from an application. If an application uses a BIO for its I/O it can transparently handle SSL connections, unencrypted network connections and file I/O. There are two type of BIO, a source/sink BIO and a filter BIO. As its name implies a source/sink BIO is a source and/or sink of data, examples include a socket BIO and a file BIO. A filter BIO takes data from one BIO and passes it through to another, or the application. The data may be left unmodified (for example a message digest BIO) or translated (for example an encryption BIO). The effect of a filter BIO may change according to the I/O operation it is performing: for example an encryption BIO will encrypt data if it is being written to and decrypt data if it is being read from. BIOs can be joined together to form a chain (a single BIO is a chain with one component). A chain normally consist of one source/sink BIO and one or more filter BIOs. Data read from or written to the first BIO then traverses the chain to the end (normally a source/sink BIO). SEE ALSO
BIO_ctrl(3), BIO_f_base64(3), BIO_f_buffer(3), BIO_f_cipher(3), BIO_f_md(3), BIO_f_null(3), BIO_f_ssl(3), BIO_find_type(3), BIO_new(3), BIO_new_bio_pair(3), BIO_push(3), BIO_read(3), BIO_s_accept(3), BIO_s_bio(3), BIO_s_connect(3), BIO_s_fd(3), BIO_s_file(3), BIO_s_mem(3), BIO_s_null(3), BIO_s_socket(3), BIO_set_callback(3), BIO_should_retry(3) 50 2013-03-05 bio(3)

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BIO_new(3)							      OpenSSL								BIO_new(3)

NAME
BIO_new, BIO_set, BIO_free, BIO_vfree, BIO_free_all - BIO allocation and freeing functions SYNOPSIS
#include <openssl/bio.h> BIO * BIO_new(BIO_METHOD *type); int BIO_set(BIO *a,BIO_METHOD *type); int BIO_free(BIO *a); void BIO_vfree(BIO *a); void BIO_free_all(BIO *a); DESCRIPTION
The BIO_new() function returns a new BIO using method type. BIO_set() sets the method of an already existing BIO. BIO_free() frees up a single BIO, BIO_vfree() also frees up a single BIO but it does not return a value. Calling BIO_free() may also have some effect on the underlying I/O structure, for example it may close the file being referred to under certain circumstances. For more details see the individual BIO_METHOD descriptions. BIO_free_all() frees up an entire BIO chain, it does not halt if an error occurs freeing up an individual BIO in the chain. RETURN VALUES
BIO_new() returns a newly created BIO or NULL if the call fails. BIO_set(), BIO_free() return 1 for success and 0 for failure. BIO_free_all() and BIO_vfree() do not return values. NOTES
Some BIOs (such as memory BIOs) can be used immediately after calling BIO_new(). Others (such as file BIOs) need some additional initialization, and frequently a utility function exists to create and initialize such BIOs. If BIO_free() is called on a BIO chain it will only free one BIO resulting in a memory leak. Calling BIO_free_all() a single BIO has the same effect as calling BIO_free() on it other than the discarded return value. Normally the type argument is supplied by a function which returns a pointer to a BIO_METHOD. There is a naming convention for such functions: a source/sink BIO is normally called BIO_s_*() and a filter BIO BIO_f_*(); EXAMPLE
Create a memory BIO: BIO *mem = BIO_new(BIO_s_mem()); SEE ALSO
TBA 1.0.1e 2013-02-11 BIO_new(3)

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