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66 lines
1.8 KiB
Plaintext
66 lines
1.8 KiB
Plaintext
=pod
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=head1 NAME
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BIO_new, BIO_set, BIO_free, BIO_vfree, BIO_free_all - BIO allocation and freeing functions
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=head1 SYNOPSIS
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#include <openssl/bio.h>
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BIO * BIO_new(BIO_METHOD *type);
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int BIO_set(BIO *a,BIO_METHOD *type);
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int BIO_free(BIO *a);
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void BIO_vfree(BIO *a);
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void BIO_free_all(BIO *a);
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=head1 DESCRIPTION
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The BIO_new() function returns a new BIO using method B<type>.
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BIO_set() sets the method of an already existing BIO.
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BIO_free() frees up a single BIO, BIO_vfree() also frees up a single BIO
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but it does not return a value. Calling BIO_free() may also have some effect
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on the underlying I/O structure, for example it may close the file being
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referred to under certain circumstances. For more details see the individual
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BIO_METHOD descriptions.
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BIO_free_all() frees up an entire BIO chain, it does not halt if an error
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occurs freeing up an individual BIO in the chain.
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=head1 RETURN VALUES
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BIO_new() returns a newly created BIO or NULL if the call fails.
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BIO_set(), BIO_free() return 1 for success and 0 for failure.
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BIO_free_all() and BIO_vfree() do not return values.
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=head1 NOTES
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Some BIOs (such as memory BIOs) can be used immediately after calling
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BIO_new(). Others (such as file BIOs) need some additional initialization,
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and frequently a utility function exists to create and initialize such BIOs.
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If BIO_free() is called on a BIO chain it will only free one BIO resulting
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in a memory leak.
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Calling BIO_free_all() a single BIO has the same effect as calling BIO_free()
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on it other than the discarded return value.
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Normally the B<type> argument is supplied by a function which returns a
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pointer to a BIO_METHOD. There is a naming convention for such functions:
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a source/sink BIO is normally called BIO_s_*() and a filter BIO
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BIO_f_*();
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=head1 EXAMPLE
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Create a memory BIO:
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BIO *mem = BIO_new(BIO_s_mem());
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=head1 SEE ALSO
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TBA
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