External Interfaces Reference |
Allocate dynamic memory using MATLAB memory manager
C Syntax
Arguments
n
Number of elements to allocate. This must be a nonnegative number.
size
Number of bytes per element. (The C sizeof
operator calculates the number of bytes per element.)
Returns
A pointer to the start of the allocated dynamic memory, if successful. If unsuccessful in a stand-alone (nonMEX-file) application, mxCalloc
returns NULL
. If unsuccessful in a MEX-file, the MEX-file terminates and control returns to the MATLAB prompt.
mxCalloc
is unsuccessful when there is insufficient free heap space.
Description
MATLAB applications should always call mxCalloc
rather than calloc
to allocate memory. Note that mxCalloc
works differently in MEX-files than in stand-alone MATLAB applications.
In MEX-files, mxCalloc
automatically
n
elements.
n
elements to 0.
The MATLAB memory management facility maintains a list of all memory allocated by mxCalloc
. The MATLAB memory management facility automatically frees (deallocates) all of a MEX-file's parcels when control returns to the MATLAB prompt.
In stand-alone MATLAB applications, mxCalloc
calls the ANSI C calloc
function.
By default, in a MEX-file, mxCalloc
generates nonpersistent mxCalloc
data. In other words, the memory management facility automatically deallocates the memory as soon as the MEX-file ends. If you want the memory to persist after the MEX-file completes, call mexMakeMemoryPersistent
after calling mxCalloc
. If you write a MEX-file with persistent memory, be sure to register a mexAtExit
function to free allocated memory in the event your MEX-file is cleared.
When you finish using the memory allocated by mxCalloc
, call mxFree
. mxFree
deallocates the memory.
Examples
See explore.c
in the mex
subdirectory of the examples
directory, and phonebook.c
and revord.c
in the refbook
subdirectory of the examples
directory.
For additional examples, see mxcalcsinglesubscript.c
and mxsetdimensions.c
in the mx
subdirectory of the examples
directory.
See Also
mxFree
, mxDestroyArray
, mexMakeArrayPersistent
,mexMakeMemoryPersistent
, mxMalloc
mxCalcSingleSubscript | mxChar |
© 1994-2005 The MathWorks, Inc.