1=pod
2
3=head1 NAME
4
5BIO_new, BIO_set, BIO_free, BIO_vfree, BIO_free_all - BIO allocation and freeing functions
6
7=head1 SYNOPSIS
8
9 #include <openssl/bio.h>
10
11 BIO *	BIO_new(BIO_METHOD *type);
12 int	BIO_set(BIO *a,BIO_METHOD *type);
13 int	BIO_free(BIO *a);
14 void	BIO_vfree(BIO *a);
15 void	BIO_free_all(BIO *a);
16
17=head1 DESCRIPTION
18
19The BIO_new() function returns a new BIO using method B<type>.
20
21BIO_set() sets the method of an already existing BIO.
22
23BIO_free() frees up a single BIO, BIO_vfree() also frees up a single BIO
24but it does not return a value. Calling BIO_free() may also have some effect
25on the underlying I/O structure, for example it may close the file being
26referred to under certain circumstances. For more details see the individual
27BIO_METHOD descriptions.
28
29BIO_free_all() frees up an entire BIO chain, it does not halt if an error
30occurs freeing up an individual BIO in the chain.
31
32=head1 RETURN VALUES
33
34BIO_new() returns a newly created BIO or NULL if the call fails.
35
36BIO_set(), BIO_free() return 1 for success and 0 for failure.
37
38BIO_free_all() and BIO_vfree() do not return values.
39
40=head1 NOTES
41
42Some BIOs (such as memory BIOs) can be used immediately after calling
43BIO_new(). Others (such as file BIOs) need some additional initialization,
44and frequently a utility function exists to create and initialize such BIOs.
45
46If BIO_free() is called on a BIO chain it will only free one BIO resulting
47in a memory leak.
48
49Calling BIO_free_all() a single BIO has the same effect as calling BIO_free()
50on it other than the discarded return value.
51
52Normally the B<type> argument is supplied by a function which returns a
53pointer to a BIO_METHOD. There is a naming convention for such functions:
54a source/sink BIO is normally called BIO_s_*() and a filter BIO
55BIO_f_*();
56
57=head1 EXAMPLE
58
59Create a memory BIO:
60
61 BIO *mem = BIO_new(BIO_s_mem());
62
63=head1 SEE ALSO
64
65TBA
66