diff --git a/kernel/src/sys/stdio.cpp b/kernel/src/sys/stdio.cpp
index 91b1a63d..fa20d141 100644
--- a/kernel/src/sys/stdio.cpp
+++ b/kernel/src/sys/stdio.cpp
@@ -19,12 +19,12 @@ void sys_write(Context* context, const char* addr, size_t size)
 void sys_open(Context* context, const char* filename, int flags)
 {
     Task* current_task = Scheduler::current_task();
-    int fd = -1;
+    int fd;
     for (fd = 0; fd < TASK_MAX_FDS; fd++)
     {
         if (!current_task->files[fd].is_open()) break;
     }
-    if (fd == -1)
+    if (fd == TASK_MAX_FDS)
     {
         STDIO_FAIL(open, EMFILE);
         context->rax = -EMFILE;