+ return err;
+}
+
+static struct cmd2process *start_multi_file_filter(struct hashmap *hashmap, const char *cmd)
+{
+ int err;
+ struct cmd2process *entry;
+ struct child_process *process;
+ const char *argv[] = { cmd, NULL };
+
+ entry = xmalloc(sizeof(*entry));
+ entry->cmd = cmd;
+ entry->supported_capabilities = 0;
+ process = &entry->process;
+
+ child_process_init(process);
+ process->argv = argv;
+ process->use_shell = 1;
+ process->in = -1;
+ process->out = -1;
+ process->clean_on_exit = 1;
+ process->clean_on_exit_handler = stop_multi_file_filter;
+
+ if (start_command(process)) {
+ error("cannot fork to run external filter '%s'", cmd);
+ return NULL;
+ }
+
+ hashmap_entry_init(entry, strhash(cmd));
+
+ err = start_multi_file_filter_fn(entry);