Fix executing sub processes. cxxtools::posix::Exec::exec() must not allocate memory. This is not allowed in multithreading programs since it can't be ensured, that another thread do not lock the heap after a fork.
Fix executing sub processes.
cxxtools::posix::Exec::exec() must not allocate memory. This is not allowed
in multithreading programs since it can't be ensured, that another thread
do not lock the heap after a fork.

maekitalo/cxxtools,maekitalo/cxxtools,maekitalo/cxxtools,maekitalo/cxxtools