Index: src/OFFile.h
==================================================================
--- src/OFFile.h
+++ src/OFFile.h
@@ -16,13 +16,14 @@
 
 #include <sys/types.h>
 
 #import "OFSeekableStream.h"
 
-@class OFString;
 @class OFArray;
 @class OFDate;
+
+extern void of_log(OFConstantString*, ...);
 
 /**
  * \brief A class which provides functions to read, write and manipulate files.
  */
 @interface OFFile: OFSeekableStream

Index: src/OFFile.m
==================================================================
--- src/OFFile.m
+++ src/OFFile.m
@@ -16,10 +16,11 @@
 
 #include "config.h"
 
 #include <stdio.h>
 #include <string.h>
+#include <stdarg.h>
 #include <unistd.h>
 
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
@@ -35,10 +36,11 @@
 #import "OFArray.h"
 #ifdef OF_THREADS
 # import "OFThread.h"
 #endif
 #import "OFDate.h"
+#import "OFApplication.h"
 #import "OFAutoreleasePool.h"
 #import "OFExceptions.h"
 #import "macros.h"
 
 #ifdef _WIN32
@@ -100,10 +102,30 @@
 	if (!strcmp(mode, "ab+") || !strcmp(mode, "a+b"))
 		return O_RDWR | O_CREAT | O_APPEND | O_BINARY;
 
 	return -1;
 }
+
+void
+of_log(OFConstantString *fmt, ...)
+{
+	OFAutoreleasePool *pool = [[OFAutoreleasePool alloc] init];
+	OFString *date, *me, *msg;
+	va_list args;
+
+	date = [[OFDate date] localDateStringWithFormat: @"%Y-%m-%dT%H:%M:%S"];
+	me = [OFFile lastComponentOfPath: [OFApplication programName]];
+
+	va_start(args, fmt);
+	msg = [[[OFString alloc] initWithFormat: fmt
+				      arguments: args] autorelease];
+	va_end(args);
+
+	[of_stderr writeFormat: @"[%@ %@(%d)] %@\n", date, me, getpid(), msg];
+
+	[pool release];
+}
 
 @interface OFFileSingleton: OFFile
 @end
 
 @implementation OFFile