diff --git a/include/h.h b/include/h.h
index efb96d996..ebce77dec 100644
--- a/include/h.h
+++ b/include/h.h
@@ -194,7 +194,7 @@ extern MODVAR char *debugmode, *configfile, *sbrk0;
 extern char *getfield(char *);
 extern void set_sockhost(Client *, const char *);
 #ifdef _WIN32
-extern char *sock_strerror(int);
+extern const char *sock_strerror(int);
 #endif
 extern int dgets(int, char *, int);
 
@@ -657,8 +657,8 @@ extern int callbacks_check(void);
 extern void callbacks_switchover(void);
 extern int efunctions_check(void);
 extern void efunctions_switchover(void);
-extern char *encode_ip(char *);
-extern char *decode_ip(char *);
+extern char *encode_ip(const char *);
+extern char *decode_ip(const char *);
 extern void sendto_one_nickcmd(Client *server, MessageTag *mtags, Client *client, char *umodes);
 extern int on_dccallow_list(Client *to, Client *from);
 extern int add_dccallow(Client *client, Client *optr);
@@ -919,7 +919,7 @@ extern CMD_FUNC(cmd_rehash);
 extern CMD_FUNC(cmd_die);
 extern CMD_FUNC(cmd_restart);
 extern void cmd_alias(Client *client, MessageTag *recv_mtags, int parc, char *parv[], char *cmd); /* special! */
-extern char *pcre2_version(void);
+extern const char *pcre2_version(void);
 extern int get_terminal_width(void);
 extern int has_common_channels(Client *c1, Client *c2);
 extern int user_can_see_member(Client *user, Client *target, Channel *channel);
@@ -1048,11 +1048,11 @@ extern void add_fmt_nvplist(NameValuePrioList **lst, int priority, const char *n
 extern NameValuePrioList *find_nvplist(NameValuePrioList *list, const char *name);
 extern void free_nvplist(NameValuePrioList *lst);
 extern const char *get_connect_extinfo(Client *client);
-extern char *unreal_strftime(char *str);
+extern char *unreal_strftime(const char *str);
 extern void strtolower(char *str);
-extern void strtolower_safe(char *dst, char *src, int size);
+extern void strtolower_safe(char *dst, const char *src, int size);
 extern void strtoupper(char *str);
-extern void strtoupper_safe(char *dst, char *src, int size);
+extern void strtoupper_safe(char *dst, const char *src, int size);
 extern int running_interactively(void);
 extern int terminal_supports_color(void);
 extern void skip_whitespace(char **p);
diff --git a/include/proto.h b/include/proto.h
index c1b5f59c8..d5d2d5c19 100644
--- a/include/proto.h
+++ b/include/proto.h
@@ -43,7 +43,7 @@ extern EVENT(handshake_timeout);
 extern EVENT(check_deadsockets);
 extern EVENT(try_connections);
 /* support.c */
-extern char *my_itoa(int i);
+extern const char *my_itoa(int i);
 
 /* s_serv.c */
 extern void load_tunefile(void);
diff --git a/src/support.c b/src/support.c
index de74c99a8..c2243232b 100644
--- a/src/support.c
+++ b/src/support.c
@@ -34,7 +34,7 @@ extern void outofmemory();
 #define is_enabled match
 
 /** Convert integer to string */
-char *my_itoa(int i)
+const char *my_itoa(int i)
 {
 	static char buf[128];
 	ircsnprintf(buf, sizeof(buf), "%d", i);
@@ -1056,7 +1056,7 @@ time_t unreal_getfilemodtime(const char *filename)
 #endif
 
 /** Encode an IP string (eg: "1.2.3.4") to a BASE64 encoded value for S2S traffic */
-char *encode_ip(char *ip)
+char *encode_ip(const char *ip)
 {
 	static char retbuf[25]; /* returned string */
 	char addrbuf[16];
@@ -1089,7 +1089,7 @@ char *encode_ip(char *ip)
 }
 
 /** Decode a BASE64 encoded string to an IP address string. Used for S2S traffic. */
-char *decode_ip(char *buf)
+char *decode_ip(const char *buf)
 {
 	int n;
 	char targ[25];
@@ -1183,7 +1183,7 @@ struct u_WSA_errors WSAErrors[] = {
 };
 
 /** Get socket error string */
-char *sock_strerror(int error)
+const char *sock_strerror(int error)
 {
 	static char unkerr[64];
 	int start = 0;
@@ -1299,7 +1299,7 @@ literal:
 }
 
 /** Return the PCRE2 library version in use */
-char *pcre2_version(void)
+const char *pcre2_version(void)
 {
 	static char buf[256];
 
@@ -1350,7 +1350,7 @@ int get_terminal_width(void)
 #endif
 
 /** Like strftime() but easier. */
-char *unreal_strftime(char *str)
+char *unreal_strftime(const char *str)
 {
 	time_t t;
 	struct tm *tmp;
@@ -1359,7 +1359,11 @@ char *unreal_strftime(char *str)
 	t = time(NULL);
 	tmp = localtime(&t);
 	if (!tmp || !strftime(buf, sizeof(buf), str, tmp))
-		return str;
+	{
+		/* If anything fails bigtime, then return the format string */
+		strlcpy(buf, str, sizeof(buf));
+		return buf;
+	}
 	return buf;
 }
 
@@ -1368,7 +1372,7 @@ char *unreal_strftime(char *str)
 #endif
 
 /** Convert a string to lowercase - with separate input/output buffer */
-void strtolower_safe(char *dst, char *src, int size)
+void strtolower_safe(char *dst, const char *src, int size)
 {
 	if (!size)
 		return; /* size of 0 is unworkable */
@@ -1390,7 +1394,7 @@ void strtolower(char *str)
 }
 
 /** Convert a string to uppercase - with separate input/output buffer */
-void strtoupper_safe(char *dst, char *src, int size)
+void strtoupper_safe(char *dst, const char *src, int size)
 {
 	if (!size)
 		return; /* size of 0 is unworkable */