diff --git a/app/src/file_handler.c b/app/src/file_handler.c
index 3ad92c05..930fd218 100644
--- a/app/src/file_handler.c
+++ b/app/src/file_handler.c
@@ -178,7 +178,7 @@ file_handler_stop(struct file_handler *file_handler) {
         if (!process_terminate(file_handler->current_process)) {
             LOGW("Could not terminate install process");
         }
-        process_wait(file_handler->current_process, NULL);
+        process_wait(file_handler->current_process); // ignore exit code
         file_handler->current_process = PROCESS_NONE;
     }
     mutex_unlock(file_handler->mutex);
diff --git a/app/src/server.c b/app/src/server.c
index 841af82f..c5982b18 100644
--- a/app/src/server.c
+++ b/app/src/server.c
@@ -391,7 +391,7 @@ server_init(struct server *server) {
 static int
 run_wait_server(void *data) {
     struct server *server = data;
-    process_wait_noclose(server->process, NULL); // ignore exit code
+    process_wait_noclose(server->process); // ignore exit code
 
     mutex_lock(server->mutex);
     server->process_terminated = true;
@@ -447,7 +447,7 @@ server_start(struct server *server, const char *serial,
         SDL_CreateThread(run_wait_server, "wait-server", server);
     if (!server->wait_server_thread) {
         process_terminate(server->process);
-        process_wait(server->process, NULL); // ignore exit code
+        process_wait(server->process); // ignore exit code
         goto error2;
     }
 
diff --git a/app/src/sys/unix/process.c b/app/src/sys/unix/process.c
index 3bb55010..2d1d0ff7 100644
--- a/app/src/sys/unix/process.c
+++ b/app/src/sys/unix/process.c
@@ -121,8 +121,8 @@ process_terminate(pid_t pid) {
     return kill(pid, SIGTERM) != -1;
 }
 
-static bool
-process_wait_internal(pid_t pid, int *exit_code, bool close) {
+static exit_code_t
+process_wait_internal(pid_t pid, bool close) {
     int code;
     int options = WEXITED;
     if (!close) {
@@ -133,29 +133,26 @@ process_wait_internal(pid_t pid, int *exit_code, bool close) {
     int r = waitid(P_PID, pid, &info, options);
     if (r == -1 || info.si_code != CLD_EXITED) {
         // could not wait, or exited unexpectedly, probably by a signal
-        code = -1;
+        code = NO_EXIT_CODE;
     } else {
         code = info.si_status;
     }
-    if (exit_code) {
-        *exit_code = code;
-    }
-    return !code;
+    return code;
 }
 
-bool
-process_wait(pid_t pid, int *exit_code) {
-    return process_wait_internal(pid, exit_code, true);
+exit_code_t
+process_wait(pid_t pid) {
+    return process_wait_internal(pid, true);
 }
 
-bool
-process_wait_noclose(pid_t pid, int *exit_code) {
-    return process_wait_internal(pid, exit_code, false);
+exit_code_t
+process_wait_noclose(pid_t pid) {
+    return process_wait_internal(pid, false);
 }
 
 void
 process_close(pid_t pid) {
-    process_wait_internal(pid, NULL, true);
+    process_wait_internal(pid, true); // ignore exit code
 }
 
 char *
diff --git a/app/src/sys/win/process.c b/app/src/sys/win/process.c
index f087625c..bb5d9bc6 100644
--- a/app/src/sys/win/process.c
+++ b/app/src/sys/win/process.c
@@ -59,31 +59,28 @@ process_terminate(HANDLE handle) {
     return TerminateProcess(handle, 1);
 }
 
-static bool
-process_wait_internal(HANDLE handle, DWORD *exit_code, bool close) {
+static exit_code_t
+process_wait_internal(HANDLE handle, bool close) {
     DWORD code;
     if (WaitForSingleObject(handle, INFINITE) != WAIT_OBJECT_0
             || !GetExitCodeProcess(handle, &code)) {
         // could not wait or retrieve the exit code
-        code = -1; // max value, it's unsigned
-    }
-    if (exit_code) {
-        *exit_code = code;
+        code = NO_EXIT_CODE; // max value, it's unsigned
     }
     if (close) {
         CloseHandle(handle);
     }
-    return !code;
+    return code;
 }
 
-bool
-process_wait(HANDLE handle, DWORD *exit_code) {
-    return process_wait_internal(handle, exit_code, true);
+exit_code_t
+process_wait(HANDLE handle) {
+    return process_wait_internal(handle, true);
 }
 
-bool
-process_wait_noclose(HANDLE handle, DWORD *exit_code) {
-    return process_wait_internal(handle, exit_code, false);
+exit_code_t
+process_wait_noclose(HANDLE handle) {
+    return process_wait_internal(handle, false);
 }
 
 void
diff --git a/app/src/util/process.c b/app/src/util/process.c
index e485ce17..e9d71d86 100644
--- a/app/src/util/process.c
+++ b/app/src/util/process.c
@@ -8,8 +8,8 @@ process_check_success(process_t proc, const char *name) {
         LOGE("Could not execute \"%s\"", name);
         return false;
     }
-    exit_code_t exit_code;
-    if (!process_wait(proc, &exit_code)) {
+    exit_code_t exit_code = process_wait(proc);
+    if (exit_code) {
         if (exit_code != NO_EXIT_CODE) {
             LOGE("\"%s\" returned with value %" PRIexitcode, name, exit_code);
         } else {
diff --git a/app/src/util/process.h b/app/src/util/process.h
index 46e481bb..e199e317 100644
--- a/app/src/util/process.h
+++ b/app/src/util/process.h
@@ -47,12 +47,12 @@ bool
 process_terminate(process_t pid);
 
 // wait and close the process (like waitpid())
-bool
-process_wait(process_t pid, exit_code_t *exit_code);
+exit_code_t
+process_wait(process_t pid);
 
 // wait (but does not close) the process (waitid() with WNOWAIT)
-bool
-process_wait_noclose(process_t pid, exit_code_t *exit_code);
+exit_code_t
+process_wait_noclose(process_t pid);
 
 // close the process
 //