◄Summary► ◄Example► ◄Up► ◄Contents► ◄Index► ◄Back► ─────Run-Time Library─────────────────────────────────────────────────────── The _vheapinit routine initializes the virtual memory manager in preparation for future allocations. It must be called before any virtual memory blocks are requested. The <dosmin> argument represents the minimum amount of DOS memory that must be available for the virtual memory manager to install itself, in paragraphs. The _vheapinit function may round up the minimum value specified. If, after rounding, the minimum amount of DOS memory is not available, _vheapinit does not initialize the virtual memory manager and returns 0. The virtual memory manager requires several kilobytes to function effectively. The <dosmax> argument represents the maximum amount of DOS memory that the virtual memory manager can use, in paragraphs. If _VM_ALLDOS is specified for the <dosmax> argument, the virtual memory manager uses all available DOS memory. The <swaparea> argument specifies which types of auxiliary memory the virtual memory manager can use to hold blocks of memory that are swapped out. The argument can be one or more of the following manifest constants, combined with the bitwise-OR operator (|): Value Meaning _VM_EMS Use expanded memory _VM_XMS Use extended memory _VM_DISK Use disk space _VM_ALLSWAP ( _VM_EMS | _VM_XMS | _VM_DISK ) If not all of the specified forms of storage are available, the virtual memory manager uses what is available. After the program is done using virtual memory, it must call _vheapterm to terminate the virtual memory manager. A program can contain multiple pairs of _vheapinit/_vheapterm calls. WARNING: If the program terminates without a call to _vheapterm, various system memory resources may not be available to subsequent programs. To specify that no minimum amount of memory is required for installation of the virtual memory manager and to use all available DOS memory in the virtual heap and all auxiliary storage, use the following command: if( _vheapinit( 0, _VM_ALLDOS, _VM_ALLSWAP) == 0 ) /* Error */ Return Value The _vheapinit function returns a nonzero value if the virtual memory manager was successfully initialized. Otherwise, it returns zero. -♦-