diff --git a/src/event/modules/ngx_select_module.c b/src/event/modules/ngx_select_module.c
index ed71368..5169055 100644
--- a/src/event/modules/ngx_select_module.c
+++ b/src/event/modules/ngx_select_module.c
@@ -288,7 +288,7 @@
 
         ngx_log_error(level, cycle->log, err, "select() failed");
 
-        if (err == EBADF) {
+        if (err == NGX_EBADF) {
             ngx_select_repair_fd_sets(cycle);
         }
 
diff --git a/src/os/unix/ngx_errno.h b/src/os/unix/ngx_errno.h
index 1497c5f..6d1a488 100644
--- a/src/os/unix/ngx_errno.h
+++ b/src/os/unix/ngx_errno.h
@@ -50,6 +50,7 @@
 #define NGX_EILSEQ        EILSEQ
 #define NGX_ENOMOREFILES  0
 #define NGX_ELOOP         ELOOP
+#define NGX_EBADF         EBADF
 
 #if (NGX_HAVE_OPENAT)
 #define NGX_EMLINK        EMLINK
diff --git a/src/os/win32/ngx_errno.h b/src/os/win32/ngx_errno.h
index decb6fe..113c7c4 100644
--- a/src/os/win32/ngx_errno.h
+++ b/src/os/win32/ngx_errno.h
@@ -52,6 +52,7 @@
 #define NGX_ENOMOREFILES           ERROR_NO_MORE_FILES
 #define NGX_EILSEQ                 ERROR_NO_UNICODE_TRANSLATION
 #define NGX_ELOOP                  0
+#define NGX_EBADF                  WSAEBADF
 
 #define NGX_EALREADY               WSAEALREADY
 #define NGX_EINVAL                 WSAEINVAL