怎麼查看動態分配內存空間的大小(GNU Linux下C語言版) ，經過幾番糾結，終於找到了GNU like UNIX平台下得到malloc後的大小的方法，
microsoft有_msize可完成類似功能，現將測試代碼甩上來，以咨參考
/********************************************************************
* Function: Test malloc and realloc,get malloc size
* Author : Samson
* Date : 11/23/2011
* Test platform:
* GNU Linux version 2.6.29.4
* gcc version 4.4.0 20090506 (Red Hat 4.4.0-4) (GCC)
* Online citations: http://fuse4bsd.creo.hu/localcgi/man-cgi.cgi?malloc+3
* *****************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
int
main()
{
char *strP, *tem2P;
int ntem;
strP = malloc(20);
ntem = malloc_usable_size(strP);
printf("first malloc_usable_size is %d\n", ntem);
tem2P = strP;
if(NULL != realloc(strP, 100))
{
ntem = malloc_usable_size(strP);
printf("realloc malloc_usable_size is %d\n", ntem);
}
free(tem2P);
exit(0);
}
run result:
[root@UFO]# ./a.out
first malloc_usable_size is 20
realloc malloc_usable_size is 100
