用mtrace定位內(nèi)存泄漏

ubuntu@VM-0-15-ubuntu:~$ man mtraceMTRACE(1)                                       Linux user manual                                       MTRACE(1)
NAME       mtrace - interpret the malloc trace log
SYNOPSIS       mtrace [option]... [binary] mtracedata
DESCRIPTION       mtrace  is a Perl script used to interpret and provide human readable output of the trace log contained in       the file mtracedata, whose contents were produced by mtrace(3).  If binary  is  provided,  the  output  of       mtrace  also  contains  the  source file name with line number information for problem locations (assuming       that binary was compiled with debugging information).
???????For?more?information?about?the?mtrace(3)?function?and?mtrace?script?usage,?see?mtrace(3).

ubuntu@VM-0-15-ubuntu:~$ man mtrace(3)-bash: syntax error near unexpected token `('ubuntu@VM-0-15-ubuntu:~$

ubuntu@VM-0-15-ubuntu:~$ man 3 mtraceMTRACE(3)                                   Linux Programmer's Manual                                   MTRACE(3)
NAME       mtrace, muntrace - malloc tracing
SYNOPSIS       #include 
       void mtrace(void);
       void muntrace(void);
DESCRIPTION       The  mtrace()  function installs hook functions for the memory-allocation functions (malloc(3), realloc(3)       memalign(3), free(3)).  These hook functions record tracing information about memory allocation and  deal[m       location.   The tracing information can be used to discover memory leaks and attempts to free nonallocated       memory in a program.
       The muntrace() function disables the hook functions installed by mtrace(), so that tracing information  is       no  longer recorded for the memory-allocation functions.  If no hook functions were successfully installed       by mtrace(), muntrace() does nothing.
       When mtrace() is called, it checks the value of the environment variable MALLOC_TRACE, which  should  con[m       tain  the  pathname of a file in which the tracing information is to be recorded.  If the pathname is suc[m       cessfully opened, it is truncated to zero length.
       If MALLOC_TRACE is not set, or the pathname it specifies is invalid or not writable, then  no  hook  func[m       tions  are  installed, and mtrace() has no effect.  In set-user-ID and set-group-ID programs, MALLOC_TRACE       is ignored, and mtrace() has no effect.

#include 
int main(){????setenv("MALLOC_TRACE",?"test.log",?"1");    mtrace();
    int *p = (int *)malloc(2 * sizeof(int));
    return 0;}

ubuntu@VM-0-15-ubuntu:~$ gcc -g test.cubuntu@VM-0-15-ubuntu:~$ ubuntu@VM-0-15-ubuntu:~$ ubuntu@VM-0-15-ubuntu:~$ ./a.outubuntu@VM-0-15-ubuntu:~$ ls test.log test.logubuntu@VM-0-15-ubuntu:~$ cat test.log = Start@ ./a.out:[0x4005eb] + 0x1649570 0x8@ /lib/x86_64-linux-gnu/libc.so.6:(clearenv+0x5d)[0x7f1bc48f7e9d] - 0x1649010@ /lib/x86_64-linux-gnu/libc.so.6:(tdestroy+0x4cf)[0x7f1bc49c291f] - 0x16490e0@ /lib/x86_64-linux-gnu/libc.so.6:[0x7f1bc4a3223c] - 0x1649100

ubuntu@VM-0-15-ubuntu:~$ mtrace a.out test.log- 0x00000000018ab010 Free 3 was never alloc'd 0x7fb41725fe9d- 0x00000000018ab0e0 Free 4 was never alloc'd 0x7fb41732a91f- 0x00000000018ab100 Free 5 was never alloc'd 0x7fb41739a23c
Memory not freed:-----------------           Address     Size     Caller0x00000000018ab570??????0x8??at?/home/ubuntu/test.c:8ubuntu@VM-0-15-ubuntu:~$

#include 
int main(){????setenv("MALLOC_TRACE",?"test.log",?"1");    mtrace();
    int *p = (int *)malloc(2 * sizeof(int));    free(p);
    return 0;}

ubuntu@VM-0-15-ubuntu:~$ gcc -g test.cubuntu@VM-0-15-ubuntu:~$ ubuntu@VM-0-15-ubuntu:~$ ubuntu@VM-0-15-ubuntu:~$ ./a.outubuntu@VM-0-15-ubuntu:~$ mtrace a.out test.log- 0x00000000006ad010 Free 4 was never alloc'd 0x7faa9b044e9d- 0x00000000006ad0e0 Free 5 was never alloc'd 0x7faa9b10f91f- 0x00000000006ad100 Free 6 was never alloc'd 0x7faa9b17f23cNo memory leaks.ubuntu@VM-0-15-ubuntu:~$