--- a/th_util.c	Wed May 21 22:31:10 2014 +0300
+++ b/th_util.c	Thu May 22 03:29:08 2014 +0300
@@ -7,6 +7,8 @@
  */
 #include "th_util.h"
 #include <stdio.h>
+#include <errno.h>
+
 
 /* Default settings
  */
@@ -122,6 +124,49 @@
 }
 
 
+/* Error handling
+ */
+int th_get_errno()
+{
+    return TH_SYSTEM_ERRORS + errno;
+}
+
+
+const char *th_error_str(int error)
+{
+    if (error >= TH_SYSTEM_ERRORS)
+        return strerror(error - TH_SYSTEM_ERRORS);
+    
+    switch (error)
+    {
+        case THERR_OK:               return "No error";
+        case THERR_FOPEN:            return "File open error";
+        case THERR_FREAD:            return "Read error";
+        case THERR_FWRITE:           return "Write error";
+        case THERR_FSEEK:            return "Seek error";
+        case THERR_NOT_FOUND:        return "Resource not found";
+
+        case THERR_INVALID_DATA:     return "Invalid data";
+        case THERR_MALLOC:           return "Memory allocation failure";
+        case THERR_ALREADY_INIT:     return "Already initialized";
+        case THERR_INIT_FAIL:        return "Initialization failed";
+        case THERR_INVALID_ARGS:     return "Invalid arguments";
+
+        case THERR_NULLPTR:          return "NULL pointer";
+        case THERR_NOT_SUPPORTED:    return "Operation not supported";
+        case THERR_OUT_OF_DATA:      return "Out of data";
+        case THERR_EXTRA_DATA:       return "Extra data";
+        case THERR_BOUNDS:           return "Bounds check failed";
+
+        case THERR_TIMED_OUT:        return "Operation timed out";
+        
+        case THERR_AUTH_FAILED:      return "Authentication failed";
+
+        default:                     return "Unknown error";
+    }
+}
+
+
 /* Memory handling routines
  */
 void *th_malloc(size_t l)

--- a/th_util.h	Wed May 21 22:31:10 2014 +0300
+++ b/th_util.h	Thu May 22 03:29:08 2014 +0300
@@ -58,6 +58,42 @@
 #  endif
 #endif
 
+
+/* Error codes
+ */
+enum {
+    // General error codes
+    THERR_OK = 0,
+    THERR_PROGRESS,     // Status OK, but operation in progress
+
+    THERR_INTERNAL,
+	
+    THERR_FOPEN,
+    THERR_FREAD,
+    THERR_FWRITE,
+    THERR_FSEEK,
+    THERR_NOT_FOUND,    // Resource/data not found
+
+    THERR_INVALID_DATA, // Some data was invalid
+    THERR_MALLOC,       // Memory allocation failure
+    THERR_ALREADY_INIT, // Resource has already been initialized
+    THERR_INIT_FAIL,    // General initialization failure
+    THERR_INVALID_ARGS,
+
+    THERR_NULLPTR,      // NULL pointer specified in critical argument
+    THERR_NOT_SUPPORTED,// Operation not supported
+    THERR_OUT_OF_DATA,
+    THERR_EXTRA_DATA,
+    THERR_BOUNDS,
+    THERR_TIMED_OUT,
+
+    // Network errors
+    THERR_AUTH_FAILED,
+};
+
+#define TH_SYSTEM_ERRORS 100000
+
+
 /* Global variables
  */
 extern int  th_verbosityLevel;
@@ -73,6 +109,9 @@
                char *author, char *license);
 void    th_print_banner(FILE *outFile, const char *binName, const char *usage);
 
+int     th_get_errno();
+const char *th_error_str(int error);
+
 void    THERR(const char *, ...);
 void    THMSG(int, const char *, ...);
 void    THPRINT(int, const char *, ...);