Hi all,

One of our programmers asked me a C programming question today that I
thought I'd ask this list about.  Since there is already a thread of C
programming questions for Linux systems..

We have a C program that has a memory leak.  We are 100% sure it has a
memory leak.  We do not know how to go about discovering the cause or
source of the memory leak.  The program runs under Linux/glibc21 of course.
Here is an output from lsof:

[32] root@host.name:/root > lsof | grep post
postman   23567 nobody  cwd    DIR        8,6        0     538752 /home/x/build/junk/src (deleted)
postman   23567 nobody  rtd    DIR        8,6     4096          2 /
postman   23567 nobody  txt    REG        8,6   144528     164860 /usr/local/bin/postman
postman   23567 nobody  mem    REG        8,6   344890     373903 /lib/ld-2.1.2.so
postman   23567 nobody  mem    REG        8,6  4118299     373910 /lib/libc-2.1.2.so
postman   23567 nobody  mem    REG        8,6   247348     373941 /lib/libnss_files-2.1.2.so
postman   23567 nobody    0r   CHR        1,3              260134 /dev/null
postman   23567 nobody    1u   CHR      136,2                   4 /dev/pts/2
postman   23567 nobody    2u   CHR      136,2                   4 /dev/pts/2

As you can see it is using 4MB of VM in libc 2.1.2 related functions.  However,
the total VM size of postman (according to ps & top) is 64MB.  Apparently postman
failing to release or otherwise cleaning up its malloc()ed memory.

Our programmer says that he has been able to find memory leaks in the
past using GUI tools such as MS Visual Studio for Windows programs.  He has
not been able to find an efficient tool for doing the same sort of searches for
memory leaks in programs on Linux systems.

We have almost ruled out gdb because it is so dense.  Undoubtedly it has the
functionality we want but it is very unfriendly.

Let me know if any of you have any ideas, thanks!

--
Jim Ockers (ockers@ockers.net)
Contact info: please see http://www.ockers.net/

Fight Spam! Join CAUCE (Coalition Against Unsolicited Commercial Email)
at http://www.cauce.org/ .