+ // Close all (presumably accidentally) inherited file descriptors to
+ // avoid descriptor leaks. This means that we don't allow inheriting
+ // them purposefully but this seems like a lesser evil in wx code.
+ // Ideally we'd provide some flag to indicate that none (or some?) of
+ // the descriptors do not need to be closed but for now this is better
+ // than never closing them at all as wx code never used FD_CLOEXEC.
+
+ // Note that while the reading side of the end process detection pipe
+ // can be safely closed, we should keep the write one opened, it will
+ // be only closed when the process terminates resulting in a read
+ // notification to the parent
+ const int fdEndProc = execData.pipeEndProcDetect.Detach(wxPipe::Write);
+ execData.pipeEndProcDetect.Close();
+
+ // TODO: Iterating up to FD_SETSIZE is both inefficient (because it may
+ // be quite big) and incorrect (because in principle we could
+ // have more opened descriptions than this number). Unfortunately
+ // there is no good portable solution for closing all descriptors
+ // above a certain threshold but non-portable solutions exist for
+ // most platforms, see [http://stackoverflow.com/questions/899038/
+ // getting-the-highest-allocated-file-descriptor]
+ for ( int fd = 0; fd < (int)FD_SETSIZE; ++fd )
+ {
+ if ( fd != STDIN_FILENO &&
+ fd != STDOUT_FILENO &&
+ fd != STDERR_FILENO &&
+ fd != fdEndProc )
+ {
+ close(fd);
+ }
+ }
+
+
+ // Process additional options if we have any
+ if ( env )
+ {
+ // Change working directory if it is specified
+ if ( !env->cwd.empty() )
+ wxSetWorkingDirectory(env->cwd);
+
+ // Change environment if needed.
+ //
+ // NB: We can't use execve() currently because we allow using
+ // non full paths to wxExecute(), i.e. we want to search for
+ // the program in PATH. However it just might be simpler/better
+ // to do the search manually and use execve() envp parameter to
+ // set up the environment of the child process explicitly
+ // instead of doing what we do below.
+ if ( !env->env.empty() )
+ {
+ wxEnvVariableHashMap oldenv;
+ wxGetEnvMap(&oldenv);
+
+ // Remove unwanted variables
+ wxEnvVariableHashMap::const_iterator it;
+ for ( it = oldenv.begin(); it != oldenv.end(); ++it )
+ {
+ if ( env->env.find(it->first) == env->env.end() )
+ wxUnsetEnv(it->first);
+ }
+
+ // And add the new ones (possibly replacing the old values)
+ for ( it = env->env.begin(); it != env->env.end(); ++it )
+ wxSetEnv(it->first, it->second);
+ }
+ }
+