@
SILdoc("
Query the library's level of API support
	This function returns an API level value indicating the current supported
	functionality.  It is important to note that this level of support is
	determined at runtime and therefore can change based on the running kernel
	and system configuration (e.g. any previously loaded seccomp filters).  This
	function can be called multiple times, but it only queries the system the
	first time it is called, the API level is cached and used in subsequent calls.
	The current API levels are described below:
		0 : reserved
		1 : base level
		2 : support for the SCMP_FLTATR_CTL_TSYNC filter attribute
		    uses the seccomp(2) syscall instead of the prctl(2) syscall
		3 : support for the SCMP_FLTATR_CTL_LOG filter attribute
			support for the SCMP_ACT_LOG action
			support for the SCMP_ACT_KILL_PROCESS action
")