#include<stdio.h>#include<stdlib.h>#include<string.h>
char * f(){ char *ptr = malloc(30); ptr = "abcdefg"; printf("&ptr=%p,%s,size=%d/n",ptr,ptr,strlen(ptr)); free(ptr); return (char *)0;}
int main(){// char *p = f();//it seems that a memory freed is unuseable f(); return 0;}
[root@bogon cTest]# ./a.out &ptr=0x8048550,abcdefg,size=7*** glibc detected *** ./a.out: free(): invalid pointer: 0x08048550 ***======= Backtrace: =========/lib/libc.so.6[0xa265a5]/lib/libc.so.6(cfree+0x59)[0xa269e9]./a.out[0x8048447]./a.out[0x8048468]/lib/libc.so.6(__libc_start_main+0xdc)[0x9d2e9c]./a.out[0x8048331]======= Memory map: ========00545000-00550000 r-xp 00000000 03:01 4224575 /lib/libgcc_s-4.1.2-20080825.so.100550000-00551000 rwxp 0000a000 03:01 4224575 /lib/libgcc_s-4.1.2-20080825.so.100782000-00783000 r-xp 00782000 00:00 0 [vdso]0099a000-009b4000 r-xp 00000000 03:01 4224500 /lib/ld-2.5.so009b4000-009b5000 r-xp 00019000 03:01 4224500 /lib/ld-2.5.so009b5000-009b6000 rwxp 0001a000 03:01 4224500 /lib/ld-2.5.so009bd000-00afc000 r-xp 00000000 03:01 4224560 /lib/libc-2.5.so00afc000-00afd000 --xp 0013f000 03:01 4224560 /lib/libc-2.5.so00afd000-00aff000 r-xp 0013f000 03:01 4224560 /lib/libc-2.5.so00aff000-00b00000 rwxp 00141000 03:01 4224560 /lib/libc-2.5.so00b00000-00b03000 rwxp 00b00000 00:00 0 08048000-08049000 r-xp 00000000 03:01 98389 /root/Desktop/cTest/a.out08049000-0804a000 rw-p 00000000 03:01 98389 /root/Desktop/cTest/a.out09fce000-09fef000 rw-p 09fce000 00:00 0 [heap]b7fbf000-b7fc1000 rw-p b7fbf000 00:00 0 b7fd8000-b7fd9000 rw-p b7fd8000 00:00 0 bfd2c000-bfd41000 rw-p bffea000 00:00 0 [stack]已放弃结果不理解。
