Function SCIPcreateConsBasicKnapsack 

pub unsafe extern "C" fn SCIPcreateConsBasicKnapsack(
    scip: *mut SCIP,
    cons: *mut *mut SCIP_CONS,
    name: *const c_char,
    nvars: c_int,
    vars: *mut *mut SCIP_VAR,
    weights: *mut c_longlong,
    capacity: c_longlong,
) -> SCIP_RETCODE

creates and captures a knapsack constraint in its most basic version, i. e., all constraint flags are set to their basic value as explained for the method SCIPcreateConsKnapsack(); all flags can be set via SCIPsetConsFLAGNAME-methods in scip.h

@see SCIPcreateConsKnapsack() for information about the basic constraint flag configuration

@note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()