In Linux, mtrace is used to check general program memory overflow.

In Linux, mtrace is used to check general program memory overflow-general Linux technology-Linux programming and kernel information. The following is a detailed description. You may encounter problems such as memory overflow when writing complex programs with many pointers. Debugging is also quite tiring. In fact, there is a tool in linux that can be used for debugging. This is mtrace. Mtrace can detect memory allocation and leakage failures. Next, let's take a look at its usage.


There are four basic steps to debug a program using mtrace. Some auxiliary function functions in the gnu c function library are required.

1. Include the header file in the program to be tracked In addition, the main () function contains a function call at the very beginning: mtrace (). Mtrace () is called at the beginning of the main function. Therefore, mtrace can trace and analyze all memory allocation and release operations after the process.
2. Define an environment variable to indicate a file. This file is used to output log information. Example:
$ Export MALLOC_TRACE = mymemory. log
3. The program runs normally. The memory allocation and release operations in the program can be recorded.
4. Use mtrace to analyze log files. For example:
$ Mtrace testmem $ MALLOC_TRACE

Here is an example:

[Hwang @ langchao test] $ cat tew.trace. c
# Include
# Include
# Include

Int main ()
{
Char * hello;
Mtrace ();
Hello = (char *) malloc (20 );
Sprintf (hello, "\ nhello world! ");
Return 1;
}
[Hwang @ langchao test] $ export MALLOC_TRACE = mytrace. log
[Hwang @ langchao test] $ gcc tew.trace. c-o tew.trace
[Hwang @ langchao test] $./tew.trace
[Hwang @ langchao test] $ mtrace tew.trace mytrace. log

Memory not freed:
-----------------
Address Size Caller
0x08049860 0x14 at/usr/src/build/53700-i386/BUILD/glibc-2.2.4/csu/init. c: 0