-/* $Cambridge: exim/src/src/osfunctions.h,v 1.1 2004/10/07 10:39:01 ph10 Exp $ */
-
/*************************************************
* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2004 */
+/* Copyright (c) University of Cambridge 1995 - 2016 */
/* See the file NOTICE for conditions of use and distribution. */
/* Prototypes for os-specific functions. For utilities, we don't need the one
extern ip_address_item *os_common_find_running_interfaces(void);
#endif
-extern int os_getloadavg(void);
-extern void os_restarting_signal(int, void (*)(int));
-extern void os_non_restarting_signal(int, void (*)(int));
-extern char *os_strexit(int); /* char to match os_strsignal */
-extern char *os_strsignal(int); /* char to match strsignal in some OS */
+/* If these exist as a macro, then they're overridden away from us and we
+rely upon the system headers to provide prototype declarations for us.
+Notably, strsignal() is not in the Single Unix Specification (v3) and
+predicting constness is awkward. */
+
+#ifndef os_getloadavg
+extern int os_getloadavg(void);
+#endif
+#ifndef os_restarting_signal
+extern void os_restarting_signal(int, void (*)(int));
+#endif
+#ifndef os_non_restarting_signal
+extern void os_non_restarting_signal(int, void (*)(int));
+#endif
+#ifndef os_strexit
+extern const char *os_strexit(int); /* char to match os_strsignal */
+#endif
+#ifndef os_strsignal
+extern const char *os_strsignal(int); /* char to match strsignal in some OS */
+#endif
+#ifndef os_unsetenv
+extern int os_unsetenv(const uschar *);
+#endif
+#ifndef os_getcwd
+extern uschar *os_getcwd(uschar *, size_t);
+#endif
/* End of osfunctions.h */