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The latest version of this topic can be found at _set_new_mode.

Sets a new handler mode for malloc.

int _set_new_mode(  
   int newhandlermode   


New handler mode for malloc; valid value is 0 or 1.

Returns the previous handler mode set for malloc. A return value of 1 indicates that, on failure to allocate memory, malloc previously called the new handler routine; a return value of 0 indicates that it did not. If the newhandlermode argument does not equal 0 or 1, returns –1.

The C++ _set_new_mode function sets the new handler mode for malloc. The new handler mode indicates whether, on failure, malloc is to call the new handler routine as set by _set_new_handler. By default, malloc does not call the new handler routine on failure to allocate memory. You can override this default behavior so that, when malloc fails to allocate memory, malloc calls the new handler routine in the same way that the new operator does when it fails for the same reason. For more information, see the new and delete operators in the C++ Language Reference. To override the default, call:


early in your program or link with Newmode.obj (see Link Options).

This function validates its parameter. If newhandlermode is anything other than 0 or 1, the function invokes the invalid parameter handler, as described in Parameter Validation. If execution is allowed to continue, _set_new_mode returns -1 and sets errno to EINVAL.

RoutineRequired header

For more compatibility information, see Compatibility in the Introduction.

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.

Memory Allocation