openfam::fam::fam_get_option

Get the value for a pre-defined option in the FAM library.

Synopsis

const void *fam_get_option(char *optionName);

Description

This method can be used to retrieve values of state variables maintained within OpenFAM or set using the options argument to fam_initialize(). The supported names (and returned types) are implementation specific.

Input Arguments

Name	Description
optionName	Name of the option to be retrieved.

The following option names are available:

Name	Description	Return type	Default Value
"VERSION"	Version of the current implementation of the OpenFAM API.	char*	"3.0"
"DEFAULT_REGION_NAME"	The default Region name used with in the program.	char*	"default"
"CIS_SERVER"	Client Interface Server set by the application.	char*	"127.0.0.1"
"GRPC_PORT"	Grpc port used by Client Interface Server.	char*	"8787"
"LIBFABRIC_PROVIDER"	Libfabric provider type set by the application.	char*	"sockets"
"FAM_THREAD_MODEL"	Thread model used by the application.	char*	"FAM_THREAD_SERIALIZE"
"CIS_INTERFACE_TYPE"	Interface Type for CIS Server.	char*	"FAM_THREAD_SERIALIZE"
"OPENFAM_MODEL"	OpenFAM allocator model used by the application.	char*	"memory_server"
"FAM_CONTEXT_MODEL"	Fam context model used by the application.	char*	"FAM_CONTEXT_DEFAULT"
"PE_COUNT"	Number of PEs running the application program.	int*	1
"PE_ID"	PE id of the current program.	int*	0
"RUNTIME"	Runtime environment used by the application.	char*	"PMIX"
"NUM_CONSUMER"	Number of consumer threads running in shared memory allocator.	char*	"1"
"FAM_DEFAULT_MEMORY_TYPE"	Memory type used for region creation and allocation. (Volatile/Persistent)	char*	"VOLATILE"
"IF_DEVICE"	Device Name to be used for data path operations with remote memory servers.	char*	"cxi0" for cxi devices and "ib0" for Infiniband devices.

Note: The following options are not supported in current implementation and should not be used, even though they have default values. "DEFAULT_REGION_NAME" and "FAM_CONTEXT_MODEL"

Return Values

A pointer to the value of the option. Throws Fam_Exception on error.

Fam Error Numbers

Error	Description
FAM_ERR_INVALID	If `optionName` not found.

Notes

None.

Example

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fam/fam.h>
#include <fam/fam_exception.h>
using namespace std;
using namespace openfam;

int main(void) {
	fam *myFam = new fam(); 
	
	// ... initialization code here
	
	try {
		// assume that library version is one of the supported options
		const char * libraryVersion = (const char *)myFam->fam_get_option(strdup("VERSION"));
		printf("%s\n", libraryVersion);
	} catch (Fam_Exception& e) {
		printf("FAM API failed: %s\n", e.fam_error_msg());
		myFam->fam_abort(-1); // abort the program
		return -1;
	}
	
	// ... finalization code here

}