=pod =head1 NAME BIO_find_type, BIO_next, BIO_method_type - BIO chain traversal =head1 SYNOPSIS #include BIO *BIO_find_type(BIO *b, int bio_type); BIO *BIO_next(BIO *b); int BIO_method_type(const BIO *b); =head1 DESCRIPTION The BIO_find_type() searches for a BIO of a given type in a chain, starting at BIO B. If B is a specific type (such as B) then a search is made for a BIO of that type. If B is a general type (such as B) then the next matching BIO of the given general type is searched for. BIO_find_type() returns the next matching BIO or NULL if none is found. The following general types are defined: B, B, and B. For a list of the specific types, see the B header file. BIO_next() returns the next BIO in a chain. It can be used to traverse all BIOs in a chain or used in conjunction with BIO_find_type() to find all BIOs of a certain type. BIO_method_type() returns the type of a BIO. =head1 RETURN VALUES BIO_find_type() returns a matching BIO or NULL for no match. BIO_next() returns the next BIO in a chain. BIO_method_type() returns the type of the BIO B. =head1 EXAMPLE Traverse a chain looking for digest BIOs: BIO *btmp; btmp = in_bio; /* in_bio is chain to search through */ do { btmp = BIO_find_type(btmp, BIO_TYPE_MD); if (btmp == NULL) break; /* Not found */ /* btmp is a digest BIO, do something with it ...*/ ... btmp = BIO_next(btmp); } while (btmp); =head1 COPYRIGHT Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. Licensed under the OpenSSL license (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 L. =cut