diff --git a/src/proto/os_mswin.pro b/src/proto/os_mswin.pro
index 383dcba..cde9cea 100644
--- a/src/proto/os_mswin.pro
+++ b/src/proto/os_mswin.pro
@@ -23,6 +23,7 @@
 int mch_chdir(char *path);
 int mch_icon_load(HANDLE *iconp);
 int mch_libcall(char_u *libname, char_u *funcname, char_u *argstring, int argint, char_u **string_result, int *number_result);
+int mch_get_random(char_u *buf, int len);
 void DumpPutS(const char *psz);
 int mch_get_winpos(int *x, int *y);
 void mch_set_winpos(int x, int y);
diff --git a/src/proto/os_unix.pro b/src/proto/os_unix.pro
index 6e13de6..d9dc8d9 100644
--- a/src/proto/os_unix.pro
+++ b/src/proto/os_unix.pro
@@ -76,6 +76,7 @@
 int gpm_available(void);
 int gpm_enabled(void);
 int mch_libcall(char_u *libname, char_u *funcname, char_u *argstring, int argint, char_u **string_result, int *number_result);
+int mch_get_random(char_u *buf, int len);
 void setup_term_clip(void);
 void start_xterm_trace(int button);
 void stop_xterm_trace(void);