mbedtls_sha512_starts_ret() function
This function starts a SHA-384 or SHA-512 checksum calculation.
Arguments
ctx
The SHA-512 context to use. This must be initialized.
is384
Determines which function to use. This must be either \c for SHA-512, or \c 1 for SHA-384.
Return value
\c 0 on success. A negative error code on failure.