[Valgrind-users] Memory leak not detected

[James R. <jam...@gm...>]

I have a program that definitely has a memory leak. I can see the memory
usage of the program going up rapidly with htop until it gets killed for
consuming too much memory. Yet this is the output from sudo valgrind -v
--tool=memcheck --leak-check=full --show-reachable=yes --track-origins=yes
--log-file=memcheck.log ./my_mmap ip enp3s0 192.168.1.254 :

==234971==
==234971== HEAP SUMMARY:
==234971==     in use at exit: 235,528 bytes in 499 blocks
==234971==   total heap usage: 499,999 allocs, 499,500 frees, 18,248,456
bytes allocated
==234971==
==234971== Searching for pointers to 499 not-freed blocks
==234971== Checked 4,186,197,696 bytes
==234971==
==234971== 235,528 bytes in 499 blocks are still reachable in loss record 1
of 1
==234971==    at 0x4843839: malloc (in
/usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==234971==    by 0x48F06DD: __fopen_internal (iofopen.c:65)
==234971==    by 0x48F06DD: fopen@@GLIBC_2.2.5 (iofopen.c:86)
==234971==    by 0x10A2B6: main (my_mmap.c:466)
==234971==
==234971== LEAK SUMMARY:
==234971==    definitely lost: 0 bytes in 0 blocks
==234971==    indirectly lost: 0 bytes in 0 blocks
==234971==      possibly lost: 0 bytes in 0 blocks
==234971==    still reachable: 235,528 bytes in 499 blocks
==234971==         suppressed: 0 bytes in 0 blocks
==234971==
==234971== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

I attach the code for the program in question. It requires an input file
with one IP address per line.

Any ideas why this memory leak is not being detected by valgrind? Or what
the source of the memory leak could be?

James Read