WordPress at a glance
filter is not described

salt filter-hook . WP 2.5.0

Filters the WordPress salt.

Usage

add_filter( 'salt', 'filter_function_name_1198', 10, 2 );
function filter_function_name_1198( $cached_salt, $scheme ){
	// filter...

	return $cached_salt;
}
$cached_salt(string)
Cached salt for the given scheme.
$scheme(string)
Authentication scheme. Values include 'auth', 'secure_auth', 'logged_in', and 'nonce'.

Where the hook is called

wp_salt()
wp-includes/pluggable.php 2111
return apply_filters( 'salt', $cached_salts[ $scheme ], $scheme );
wp-includes/pluggable.php 2166
return apply_filters( 'salt', $cached_salts[ $scheme ], $scheme );

Where the hook is used (in WP core)

Does not used.