openssl/doc/crypto/buffer.pod

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=pod
=head1 NAME
BUF_MEM_new, BUF_MEM_new_ex, BUF_MEM_free, BUF_MEM_grow - simple
character array structure
standard C library equivalents
=head1 SYNOPSIS
#include <openssl/buffer.h>
BUF_MEM *BUF_MEM_new(void);
#define BUF_MEM_FLAG_SECURE
BUF_MEM *BUF_MEM_new_ex(unsigned long flags);
void BUF_MEM_free(BUF_MEM *a);
int BUF_MEM_grow(BUF_MEM *str, int len);
=head1 DESCRIPTION
The buffer library handles simple character arrays. Buffers are used for
various purposes in the library, most notably memory BIOs.
BUF_MEM_new() allocates a new buffer of zero size.
BUF_MEM_new_ex() allocates a buffer with the specified flags.
The flag B<BUF_MEM_FLAG_SECURE> specifies that the B<data> pointer
should be allocated on the secure heap; see L<CRYPTO_secure_malloc(3)>.
BUF_MEM_free() frees up an already existing buffer. The data is zeroed
before freeing up in case the buffer contains sensitive data.
BUF_MEM_grow() changes the size of an already existing buffer to
B<len>. Any data already in the buffer is preserved if it increases in
size.
=head1 RETURN VALUES
BUF_MEM_new() returns the buffer or NULL on error.
BUF_MEM_free() has no return value.
BUF_MEM_grow() returns zero on error or the new size (i.e. B<len>).
=head1 SEE ALSO
L<bio(3)>,
L<CRYPTO_secure_malloc(3)>.
=head1 HISTORY
BUF_MEM_new_ex() was added in OpenSSL 1.1.0.
=cut