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Releases unused heap memory to the operating system.

int _heapmin( void );

Return Value

If successful, _heapmin returns 0; otherwise, the function returns –1 and sets errno to ENOSYS.

See _doserrno, errno, _sys_errlist, and _sys_nerr for more information on this, and other, return codes.


The _heapmin function minimizes the heap by releasing unused heap memory to the operating system.

Note   In Visual C++ version 4.0, the underlying heap structure was moved to the C run-time libraries to support the new debugging features. As a result, the only Win32 platform that is supported by _heapmin is Windows NT. The function returns –1 and sets errno to ENOSYS, when it is called by any other Win32 platform.


Routine Required header Optional headers Compatibility
_heapmin <malloc.h> <errno.h> Win NT, Win 2000, Win XP

For additional compatibility information, see Compatibility in the Introduction.


All versions of the C run-time libraries.

See Also

Memory Allocation Routines | free | _heapadd | _heapchk | _heapset | _heapwalk | malloc | Run-Time Routines and .NET Framework Equivalents

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