diff --git a/src/lib3270/appres.h b/src/lib3270/appres.h
index 72c48ac..96aeed7 100644
--- a/src/lib3270/appres.h
+++ b/src/lib3270/appres.h
@@ -228,7 +228,7 @@ typedef struct {
 
 } AppRes, *AppResptr;
 
-LIB3270_INTERNAL AppRes appres;
+extern AppRes appres;
 
 // FIXME (perry#2#): Check for right implementation
 #define _( x ) x
diff --git a/src/lib3270/ctlr.c b/src/lib3270/ctlr.c
index c968745..4ddb39b 100644
--- a/src/lib3270/ctlr.c
+++ b/src/lib3270/ctlr.c
@@ -2841,6 +2841,7 @@ toggle_nop(H3270 *session, struct toggle *t unused, LIB3270_TOGGLE_TYPE tt unuse
 {
 }
 
+/*
 int ctlr_get_rows(void)
 {
     return h3270.rows;
@@ -2850,4 +2851,4 @@ int ctlr_get_cols(void)
 {
     return h3270.cols;
 }
-
+*/
diff --git a/src/lib3270/ctlr.h b/src/lib3270/ctlr.h
index 577458c..3056bdf 100644
--- a/src/lib3270/ctlr.h
+++ b/src/lib3270/ctlr.h
@@ -17,8 +17,5 @@
  *		External declarations for ctlr.c data structures.
  */
 
-LIB3270_INTERNAL int			buffer_addr;	/**< buffer address */
-// LIB3270_INTERNAL int			cursor_addr;	/**< cursor address */
-LIB3270_INTERNAL struct ea	*ea_buf;			/**< 3270 device buffer */
-//LIB3270_INTERNAL Boolean		formatted;		/**< contains at least one field? */
-//LIB3270_INTERNAL Boolean		is_altbuffer;	/**< in alternate-buffer mode? */
+extern int			buffer_addr;	/**< buffer address */
+extern struct ea	*ea_buf;			/**< 3270 device buffer */
diff --git a/src/lib3270/ftc.h b/src/lib3270/ftc.h
index ceda7aa..f6a67c9 100644
--- a/src/lib3270/ftc.h
+++ b/src/lib3270/ftc.h
@@ -24,7 +24,7 @@ LIB3270_INTERNAL Boolean ascii_flag;
 LIB3270_INTERNAL Boolean cr_flag;
 LIB3270_INTERNAL unsigned long ft_length;
 LIB3270_INTERNAL FILE *ft_local_file;
-LIB3270_INTERNAL char *ft_local_filename;
+extern char *ft_local_filename;
 
 LIB3270_INTERNAL Boolean ft_last_cr;
 LIB3270_INTERNAL Boolean remap_flag;
diff --git a/src/lib3270/globals.h b/src/lib3270/globals.h
index 86a9fc4..19b4036 100644
--- a/src/lib3270/globals.h
+++ b/src/lib3270/globals.h
@@ -145,7 +145,7 @@ enum iaction {
 
 LIB3270_INTERNAL int		COLS;
 LIB3270_INTERNAL int		ROWS;
-LIB3270_INTERNAL H3270		h3270;
+extern H3270		h3270;
 
 #if defined(X3270_DISPLAY) /*[*/
 	LIB3270_INTERNAL Atom		a_3270, a_registry, a_encoding;
@@ -209,7 +209,7 @@ LIB3270_INTERNAL Boolean		no_login_host;
 LIB3270_INTERNAL Boolean		non_tn3270e_host;
 // LIB3270_INTERNAL int			ov_cols, ov_rows;
  LIB3270_INTERNAL Boolean		passthru_host;
-LIB3270_INTERNAL const char	*programname;
+extern const char	*programname;
 LIB3270_INTERNAL char			*qualified_host;
 LIB3270_INTERNAL char			*reconnect_host;
 LIB3270_INTERNAL int			screen_depth;
diff --git a/src/lib3270/printer.c b/src/lib3270/printer.c
index 428fede..f1e6f81 100644
--- a/src/lib3270/printer.c
+++ b/src/lib3270/printer.c
@@ -438,8 +438,7 @@ printer_start(const char *lu)
 	    NULL,
 	    &startupinfo,
 	    &process_information) == 0) {
-		popup_an_error("CreateProcess(%s) failed: %s", subcommand,
-			win32_strerror(GetLastError()));
+		popup_an_error(NULL,"CreateProcess(%s) failed: %s", subcommand,win32_strerror(GetLastError()));
 	}
 	printer_handle = process_information.hProcess;
 	CloseHandle(process_information.hThread);
@@ -599,8 +598,7 @@ printer_check(void)
 
 		st_changed(ST_PRINTER, False);
 
-		popup_an_error("Printer process exited with status %d",
-		    exit_code);
+		popup_an_error(NULL,"Printer process exited with status %d",exit_code);
 	}
 }
 #endif /*]*/
diff --git a/src/lib3270/screen.c b/src/lib3270/screen.c
index 6ca5d66..43f246f 100644
--- a/src/lib3270/screen.c
+++ b/src/lib3270/screen.c
@@ -688,6 +688,7 @@ void show_3270_popup_dialog(H3270 *session, LIB3270_NOTIFY type, const char *tit
 static int logpopup(H3270 *session, LIB3270_NOTIFY type, const char *title, const char *msg, const char *fmt, va_list arg)
 {
 	lib3270_write_va_log(session,"lib3270",fmt,arg);
+	return 0;
 }
 
 void Error(H3270 *session, const char *fmt, ...)
diff --git a/src/lib3270/selection.c b/src/lib3270/selection.c
index 2ce2f31..412792f 100644
--- a/src/lib3270/selection.c
+++ b/src/lib3270/selection.c
@@ -166,8 +166,6 @@ LIB3270_EXPORT void lib3270_clear_selection(H3270 *session)
 
 	for(a = 0; a < session->rows*session->cols; a++)
 	{
-		unsigned short attr = ea_buf[a].attr;
-
 		if(ea_buf[a].attr & LIB3270_ATTR_SELECTED)
 		{
 			ea_buf[a].attr &= ~LIB3270_ATTR_SELECTED;
diff --git a/src/lib3270/telnet.c b/src/lib3270/telnet.c
index 06ecacd..5debf0b 100644
--- a/src/lib3270/telnet.c
+++ b/src/lib3270/telnet.c
@@ -390,33 +390,23 @@ static union {
 } haddr;
 socklen_t ha_len = sizeof(haddr);
 
-#if defined(_WIN32)
-void popup_a_sockerr(char *fmt, ...)
-{
-	va_list args;
-	char buffer[4096];
-
-	va_start(args, fmt);
-	vsprintf(buffer, fmt, args);
-	va_end(args);
-
-	popup_system_error( N_( "Network error" ), buffer, win32_strerror(socket_errno()));
-
-}
-#else
 void popup_a_sockerr(H3270 *session, char *fmt, ...)
 {
+#if defined(_WIN32)
+	const char *msg = win32_strerror(socket_errno());
+#else
+	const char *msg = strerror(errno)
+#endif // WIN32
 	va_list args;
 	char buffer[4096];
 
 	va_start(args, fmt);
-	vsprintf(buffer, fmt, args);
+	vsnprintf(buffer, 4095, fmt, args);
 	va_end(args);
 
-	popup_system_error(session, N_( "Network error" ), buffer, strerror(errno));
+	popup_system_error(session, N_( "Network error" ), buffer, "%s", msg);
 
 }
-#endif
 
 /*
  * net_connect
@@ -2780,8 +2770,7 @@ tn3270e_nak(enum pds rv)
 	}
 	rsp_buf[rsp_len++] = IAC;
 	rsp_buf[rsp_len++] = EOR;
-	trace_dsn("SENT TN3270E(RESPONSE NEGATIVE-RESPONSE %u) %s\n",
-		h_in->seq_number[0] << 8 | h_in->seq_number[1], neg);
+	trace_dsn("SENT TN3270E(RESPONSE NEGATIVE-RESPONSE %u) %s\n",h_in->seq_number[0] << 8 | h_in->seq_number[1], neg);
 	net_rawout(rsp_buf, rsp_len);
 }
 
diff --git a/src/lib3270/telnetc.h b/src/lib3270/telnetc.h
index eb1a41e..dc3c25b 100644
--- a/src/lib3270/telnetc.h
+++ b/src/lib3270/telnetc.h
@@ -20,7 +20,8 @@
  */
 
 /* Output buffer. */
-LIB3270_INTERNAL unsigned char *obuf, *obptr;
+extern unsigned char *obuf;
+extern unsigned char *obptr;
 
 /* Spelled-out tty control character. */
 struct ctl_char {
--
libgit2 0.21.2