Updated: 2022/Sep/29

Please read Privacy Policy. It's for your privacy.


BIO_new(3)                          OpenSSL                         BIO_new(3)



NAME
       BIO_new_ex, BIO_new, BIO_up_ref, BIO_free, BIO_vfree, BIO_free_all -
       BIO allocation and freeing functions

LIBRARY
       libcrypto, -lcrypto

SYNOPSIS
        #include <openssl/bio.h>

        BIO *BIO_new_ex(OSSL_LIB_CTX *libctx, const BIO_METHOD *type);
        BIO *BIO_new(const BIO_METHOD *type);
        int BIO_up_ref(BIO *a);
        int BIO_free(BIO *a);
        void BIO_vfree(BIO *a);
        void BIO_free_all(BIO *a);

DESCRIPTION
       The BIO_new_ex() function returns a new BIO using method type
       associated with the library context libctx (see OSSL_LIB_CTX(3)). The
       library context may be NULL to indicate the default library context.

       The BIO_new() is the same as BIO_new_ex() except the default library
       context is always used.

       BIO_up_ref() increments the reference count associated with the BIO
       object.

       BIO_free() frees up a single BIO, BIO_vfree() also frees up a single
       BIO but it does not return a value.  If a is NULL nothing is done.
       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.  If a is NULL
       nothing is done.

RETURN VALUES
       BIO_new_ex() and BIO_new() return a newly created BIO or NULL if the
       call fails.

       BIO_up_ref() and BIO_free() return 1 for success and 0 for failure.

       BIO_free_all() and BIO_vfree() do not return values.

NOTES
       If BIO_free() is called on a BIO chain it will only free one BIO
       resulting in a memory leak.

       Calling BIO_free_all() on a single BIO has the same effect as calling
       BIO_free() on it other than the discarded return value.

HISTORY
       BIO_set() was removed in OpenSSL 1.1.0 as BIO type is now opaque.

       BIO_new_ex() was added in OpenSSL 3.0.

EXAMPLES
       Create a memory BIO:

        BIO *mem = BIO_new(BIO_s_mem());

COPYRIGHT
       Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.



3.0.12                            2023-05-07                        BIO_new(3)