Programming Example of Working With Local sideinfo file 
RFC_OPTIONS
rfc_opt; /* Parameter for RFC connection */RfcEnvironment
(...); /* Install error handling function */rfc_opt.mode =
RFC_MODE_R3ONLY ; */ RFC to R/3 System */rfc_opt.destination = "BIN"; /* Destination in local sideinfo */
rfc_opt.connopt = NULL; /* Connect parameters in */
/* sideinfo file */
rfc_opt.client = "000"; /* Client in SAP R/3 */
rfc_opt.user = "RFCTEST"; /* CPIC or dialog user */
rfc_opt.password = "SECRET"; /* Password */
rfc_opt.language = "E"; /* Logon language */
rfc_opt.trace = 0; /* No RFC trace */
rfc_handle =
RfcOpen (&rfc_opt); /* Open RFC connection */...
Local sideinfo file:
The local sideinfo file must be in the same directory as the RFC client program or must be defined with its path and file name by the environment variable SIDE_INFO.

Windows:
The sideinfo entry for the above test could be as follows:
DEST=BIN
GWHOST=hs0311
GWSERV=sapgw53
PROTOCOL=I
LU=hs0311
TP=sapdp53