Handy gui_fatal() etc routines.

common/gui-fatal.c

@@ -0,0 +1,50 @@
+#define _GNU_SOURCE
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <malloc.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdarg.h>
+
+static void fix_display()
+{
+	setenv("DISPLAY", ":0", 1);
+}
+
+static void produce_message(char * type, const char *fmt, va_list args)
+{
+	char *kdialog_msg;
+	char buf[1024];
+	(void) vsnprintf(buf, sizeof(buf), fmt, args);
+	asprintf(&kdialog_msg, "%s: %s: %s (error type: %s)",
+		 program_invocation_short_name, type, buf, strerror(errno));
+	fprintf(stderr, "%s", kdialog_msg);
+	switch (fork()) {
+	case -1:
+		exit(1);	//what else
+	case 0:
+		fix_display();
+		execlp("kdialog", "kdialog", "--sorry", kdialog_msg, NULL);
+		exit(1);
+	default:;
+	}
+}
+
+void gui_fatal(const char *fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	produce_message("Fatal error", fmt, args);
+	va_end(args);
+	exit(1);
+}
+
+void gui_nonfatal(const char *fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	produce_message("Information", fmt, args);
+	va_end(args);
+}

common/gui-fatal.h

@@ -0,0 +1,2 @@
+void gui_fatal(const char *fmt, ...);
+void gui_nonfatal(const char *fmt, ...);