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Alphabetical listing for B

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buffer(3)
NAME
  buffer, BUF_MEM_new, BUF_MEM_free, BUF_MEM_grow, BUF_strdup - Simple
  character arrays structure

SYNOPSIS
  #include <openssl/buffer.h>

  BUF_MEM *BUF_MEM_new(
	  void );

  void	  BUF_MEM_free(
	  BUF_MEM *a );

  int	   BUF_MEM_grow(
	  BUF_MEM *str, int len );

  char * BUF_strdup(
	  const char *str );

DESCRIPTION
  The buffer library handles simple character arrays. Buffers are used for
  various purposes in the library, most notably memory BIOs.

  The library uses the BUF_MEM structure defined in buffer.h:

	typedef struct buf_mem_st
	{
	       int length;     /* current number of bytes */
	       char *data;
	       int max;	       /* size of buffer */
	} BUF_MEM;

  The length is the current size of the buffer in bytes, max is the amount of
  memory allocated to the buffer. There are three functions which handle
  these and one miscellaneous function.

  The BUF_MEM_new() function allocates a new buffer of zero size.

  The BUF_MEM_free() function frees up an already existing buffer. The data
  is zeroed before freeing up in case the buffer contains sensitive data.

  The BUF_MEM_grow() function changes the size of an already existing buffer
  to len. Any data already in the buffer is preserved if it increases in
  size.

  The BUF_strdup() function copies a null terminated string into a block of
  allocated memory and returns a pointer to the allocated block. Unlike the
  standard C library strdup(), this function uses OPENSSL_malloc(). It should
  be used in preference to the standard library strdup() because it can be
  used for memory leak checking or replacing the malloc() function.

  The memory allocated from the BUF_strdup() function should be freed up
  using the OPENSSL_free() function.

RETURN VALUES
  The BUF_MEM_new() function returns the buffer or NULL on error.

  The BUF_MEM_free() function has no return value.

  The BUF_MEM_grow() function returns zero on error or the new size (i.e.
  len).

HISTORY
  The BUF_MEM_new(), BUF_MEM_free(), and BUF_MEM_grow() functions are
  available in all versions of SSLeay and OpenSSL. The BUF_strdup() function
  was added in SSLeay 0.8.

SEE ALSO
  Function: bio(3)

Index for Section 3

Alphabetical listing for B

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