CRYPT_PREFERRED_METHOD(3) Library Functions Manual CRYPT_PREFERRED_METHOD(3)

crypt_preferred_method
get the prefix of the preferred hash method

Crypt Library (libcrypt, -lcrypt)

#include <crypt.h>

const char*
crypt_preferred_method(void);

crypt_preferred_method is a convenience function to get the prefix of the preferred hash method. If a preferred method is available, it is the same as the one also used by the crypt_gensalt functions, if their given prefix parameter is NULL.

The string returned equals the prefix of the preferred hash method. If no preferred hash method is available it is NULL. It is safe to pass the string returned by crypt_preferred_method directly to crypt_gensalt without prior string-sanitizing nor NULL-pointer checks.

<crypt.h> will define the macro CRYPT_PREFERRED_METHOD_AVAILABLE if crypt_preferred_method is available in the current version of libxcrypt.

The function crypt_preferred_method is not part of any standard. It was added to libxcrypt in version 4.4.0.

For an explanation of the terms used in this section, see attributes(7).
Interface Attribute Value
Thread safety MT-Safe

crypt_gensalt(3)
November 16, 2018 libxcrypt