static const char pre_receive_hook[] = "hooks/pre-receive";
 static const char post_receive_hook[] = "hooks/post-receive";
 
+static int copy_to_sideband(int in, int out, void *arg)
+{
+       char data[128];
+       while (1) {
+               ssize_t sz = xread(in, data, sizeof(data));
+               if (sz <= 0)
+                       break;
+               send_sideband(1, 2, data, sz, use_sideband);
+       }
+       close(in);
+       return 0;
+}
+
 static int run_receive_hook(const char *hook_name)
 {
        static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
        struct command *cmd;
        struct child_process proc;
+       struct async muxer;
        const char *argv[2];
        int have_input = 0, code;
 
        proc.in = -1;
        proc.stdout_to_stderr = 1;
 
+       if (use_sideband) {
+               memset(&muxer, 0, sizeof(muxer));
+               muxer.proc = copy_to_sideband;
+               muxer.in = -1;
+               code = start_async(&muxer);
+               if (code)
+                       return code;
+               proc.err = muxer.in;
+       }
+
        code = start_command(&proc);
-       if (code)
+       if (code) {
+               if (use_sideband)
+                       finish_async(&muxer);
                return code;
+       }
+
        for (cmd = commands; cmd; cmd = cmd->next) {
                if (!cmd->error_string) {
                        size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
                }
        }
        close(proc.in);
+       if (use_sideband)
+               finish_async(&muxer);
        return finish_command(&proc);
 }
 
 {
        static const char update_hook[] = "hooks/update";
        const char *argv[5];
+       struct child_process proc;
+       int code;
 
        if (access(update_hook, X_OK) < 0)
                return 0;
        argv[3] = sha1_to_hex(cmd->new_sha1);
        argv[4] = NULL;
 
-       return run_command_v_opt(argv, RUN_COMMAND_NO_STDIN |
-                                       RUN_COMMAND_STDOUT_TO_STDERR);
+       memset(&proc, 0, sizeof(proc));
+       proc.no_stdin = 1;
+       proc.stdout_to_stderr = 1;
+       proc.err = use_sideband ? -1 : 0;
+       proc.argv = argv;
+
+       code = start_command(&proc);
+       if (code)
+               return code;
+       if (use_sideband)
+               copy_to_sideband(proc.err, -1, NULL);
+       return finish_command(&proc);
 }
 
 static int is_ref_checked_out(const char *ref)
 static void run_update_post_hook(struct command *cmd)
 {
        struct command *cmd_p;
-       int argc, status;
+       int argc;
        const char **argv;
+       struct child_process proc;
 
        for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
                if (cmd_p->error_string)
                argc++;
        }
        argv[argc] = NULL;
-       status = run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
-                       | RUN_COMMAND_STDOUT_TO_STDERR);
+
+       memset(&proc, 0, sizeof(proc));
+       proc.no_stdin = 1;
+       proc.stdout_to_stderr = 1;
+       proc.err = use_sideband ? -1 : 0;
+       proc.argv = argv;
+
+       if (!start_command(&proc)) {
+               if (use_sideband)
+                       copy_to_sideband(proc.err, -1, NULL);
+               finish_command(&proc);
+       }
 }
 
 static void execute_commands(const char *unpacker_error)
 
 '
 
 cat <<EOF >expect
-STDOUT pre-receive
-STDERR pre-receive
-STDOUT update refs/heads/master
-STDERR update refs/heads/master
-STDOUT update refs/heads/tofail
-STDERR update refs/heads/tofail
-STDOUT post-receive
-STDERR post-receive
-STDOUT post-update
-STDERR post-update
+remote: STDOUT pre-receive
+remote: STDERR pre-receive
+remote: STDOUT update refs/heads/master
+remote: STDERR update refs/heads/master
+remote: STDOUT update refs/heads/tofail
+remote: STDERR update refs/heads/tofail
+remote: STDOUT post-receive
+remote: STDERR post-receive
+remote: STDOUT post-update
+remote: STDERR post-update
 EOF
 test_expect_success 'send-pack stderr contains hook messages' '
-       grep ^STD send.err >actual &&
+       grep ^remote: send.err | sed "s/ *\$//" >actual &&
        test_cmp - actual <expect
 '