How do I tell valgrind to memcheck forked processes?

c++ c linux fork valgrind
Nathan Fellman picture Nathan Fellman · Nov 19, 2008 · Viewed 20.3k times · Source

I have a process x that I want to check for leaks with valgrind. The problem is that x is run by y, and y in turn is run by z. I can't run x standalone because y and z setup the environment for x, such as environment variables, command line switches, files needed by x etc.

  1. Is there any way I can tell valgrind to run on z but to follow any forks it finds and report them too?
  2. Is there any way I can tell valgrind to follow any forks but only report on the process named x?
  3. Is there any way I can tell valgrind to attach to already-running process, the way I can do with gdb?

I don't know if this matters, but I'm running under SuSE64 linux and valgrind-2.4.0.

Thanks!

Answer

JesperE picture JesperE · Nov 19, 2008
  1. Valgrind follows forked processes when given the --trace-children=yes option.
  2. You should be able to achieve this by using suitable filters.
  3. No. Valgrind hooks into the module loading code using LD_PRELOAD, so attaching to a running process is not possible.

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