CRYPTO_set_ex_data, CRYPTO_get_ex_data - internal application specific data functions
Synopsis int CRYPTO_set_ex_data(CRYPTO_EX_DATA *r,
int idx, void *arg); void *CRYPTO_get_ex_data(CRYPTO_EX_DATA
*r, int idx);
DESCRIPTIONSeveral OpenSSL structures can have application specific data
attached to them. These functions are used internally by OpenSSL
to manipulate application specific data attached to a specific structure.
These functions should only be used by applications to manipulate CRYPTO_EX_DATA structures
passed to the new_func(), free_func() and dup_func() callbacks:
as passed to RSA_get_ex_new_index() for example.
CRYPTO_set_ex_data() is used to set application
specific data, the data is supplied in the arg parameter
and its precise meaning is up to the application.
CRYPTO_get_ex_data() is used to retrieve
application specific data. The data is returned to the application, this
will be the same value as supplied to a previous CRYPTO_set_ex_data() call.
RETURN VALUESCRYPTO_set_ex_data() returns 1 on success
or 0 on failure.
CRYPTO_get_ex_data() returns the application
data or 0 on failure. 0 may also be valid application data but currently
it can only fail if given an invalid idx parameter.
On failure an error code can be obtained from ERR_get_error(3) .
SEE ALSORSA_get_ex_new_index(3) , DSA_get_ex_new_index(3) , DH_get_ex_new_index(3) HISTORYCRYPTO_set_ex_data() and CRYPTO_get_ex_data() have been available
since SSLeay 0.9.0.
HP Open Source Security for OpenVMS Volume 2:... 
CRYPTO Application Programming Interface (API)... 
