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'This example uses the SETMEM function to free memory for a C function that
'uses the C routine malloc to get dynamic memory.
 
'Note: To run this program, you must separately compile the C function and
'put it in a Quick library or link it to the BASIC program. The C function
'must be compiled using the large memory model, so calls to malloc use the
'far space freed by the BASIC program.
 
DECLARE SUB CFunc CDECL (BYVAL X AS INTEGER)
 
'Decrease the size of the far heap so CFunc can use malloc
'to get dynamic memory.
BeforeCall = SETMEM(-2048)
 
'Call the C function.
CFunc(1024%)
 
'Return the memory to the far heap; use a larger value so
'all space goes back into the heap.
AfterCall = SETMEM(3500)
 
IF AfterCall <= BeforeCall THEN PRINT "Memory not reallocated."
 
END
 
 
'/* C Function */
'void far cfunc(bytes)
'int bytes;
'{
'   char *malloc();
'   char *workspace;
'
'   /* Allocate working memory using amount BASIC freed. */
'   workspace=malloc((unsigned) bytes);
'
'   /* Working space would be used here. */
'
'   /* Free memory before returning to BASIC. */
'   free(workspace);
'}