BIO_new.pod 2.2 KB

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  1. =pod
  2. =head1 NAME
  3. BIO_new_ex, BIO_new, BIO_up_ref, BIO_free, BIO_vfree, BIO_free_all
  4. - BIO allocation and freeing functions
  5. =head1 SYNOPSIS
  6. #include <openssl/bio.h>
  7. BIO *BIO_new_ex(OSSL_LIB_CTX *libctx, const BIO_METHOD *type);
  8. BIO *BIO_new(const BIO_METHOD *type);
  9. int BIO_up_ref(BIO *a);
  10. int BIO_free(BIO *a);
  11. void BIO_vfree(BIO *a);
  12. void BIO_free_all(BIO *a);
  13. =head1 DESCRIPTION
  14. The BIO_new_ex() function returns a new BIO using method B<type> associated with
  15. the library context I<libctx> (see OSSL_LIB_CTX(3)). The library context may be
  16. NULL to indicate the default library context.
  17. The BIO_new() is the same as BIO_new_ex() except the default library context is
  18. always used.
  19. BIO_up_ref() increments the reference count associated with the BIO object.
  20. BIO_free() frees up a single BIO, BIO_vfree() also frees up a single BIO
  21. but it does not return a value.
  22. If B<a> is NULL nothing is done.
  23. Calling BIO_free() may also have some effect
  24. on the underlying I/O structure, for example it may close the file being
  25. referred to under certain circumstances. For more details see the individual
  26. BIO_METHOD descriptions.
  27. BIO_free_all() frees up an entire BIO chain, it does not halt if an error
  28. occurs freeing up an individual BIO in the chain.
  29. If B<a> is NULL nothing is done.
  30. =head1 RETURN VALUES
  31. BIO_new_ex() and BIO_new() return a newly created BIO or NULL if the call fails.
  32. BIO_up_ref() and BIO_free() return 1 for success and 0 for failure.
  33. BIO_free_all() and BIO_vfree() do not return values.
  34. =head1 NOTES
  35. If BIO_free() is called on a BIO chain it will only free one BIO resulting
  36. in a memory leak.
  37. Calling BIO_free_all() on a single BIO has the same effect as calling BIO_free()
  38. on it other than the discarded return value.
  39. =head1 HISTORY
  40. BIO_set() was removed in OpenSSL 1.1.0 as BIO type is now opaque.
  41. BIO_new_ex() was added in OpenSSL 3.0.
  42. =head1 EXAMPLES
  43. Create a memory BIO:
  44. BIO *mem = BIO_new(BIO_s_mem());
  45. =head1 COPYRIGHT
  46. Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.
  47. Licensed under the Apache License 2.0 (the "License"). You may not use
  48. this file except in compliance with the License. You can obtain a copy
  49. in the file LICENSE in the source distribution or at
  50. L<https://www.openssl.org/source/license.html>.
  51. =cut