Hi Andy,
I recommend IBM Rational PurifyPlus for Linux, and IBM Rational PurifyPlus for Unix (Solaris).
q.v. <http://www.rational.com/products/pqc/index.jsp>
Or, alternatively, you can write your own general-purpose new, delete, new[] and delete[] (and/or malloc/alloc/realloc/free) routines which you've instrumented with start/end sentinels (for write-overruns) and allocation tracking (for memory leaks).
For a cheaper solution, try running your code through Borland's CodeGuard. (Is CodeGuard still around...?)
Eljay,
Thanks. I've used Purify previously and was happy with it. I checked out the site, but could not get a price, as they are moving it over to IBM's site.
This is for my own enjoyment, so I'm looking for something on the cheap, preferably open source.
Andy