From: solar <unknown>
Date: Thu, 6 Jul 2006 05:17:17 +0000 (+0000)
Subject: Improved testdrivers.
X-Git-Tag: v0.5~148
X-Git-Url: https://pd.if.org/git/?p=pdclib;a=commitdiff_plain;h=d9e48b611b63bcfc55727463cb9d9d0e87a7a405

Improved testdrivers.
---

diff --git a/functions/_PDCLIB/filemode.c b/functions/_PDCLIB/filemode.c
new file mode 100644
index 0000000..460cc6e
--- /dev/null
+++ b/functions/_PDCLIB/filemode.c
@@ -0,0 +1,88 @@
+/* $Id$ */
+
+/* _PDCLIB_filemode( const char * )
+
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#ifndef REGTEST
+
+#include <stddef.h>
+
+/* Helper function that parses the C-style mode string passed to fopen() into
+   the PDCLib flags FREAD, FWRITE, FAPPEND, FRW (read-write) and FBIN (binary
+   mode).
+*/
+unsigned int _PDCLIB_filemode( char const * const mode )
+{
+    int rc = 0;
+    switch ( mode[0] )
+    {
+        case 'r':
+            rc |= _PDCLIB_FREAD;
+            break;
+        case 'w':
+            rc |= _PDCLIB_FWRITE;
+            break;
+        case 'a':
+            rc |= _PDCLIB_FAPPEND;
+            break;
+        default:
+            /* Other than read, write, or append - invalid */
+            return 0;
+    }
+    for ( size_t i = 1; i < 4; ++i )
+    {
+        switch ( mode[i] )
+        {
+            case '+':
+                if ( rc & _PDCLIB_FRW ) return 0; /* Duplicates are invalid */
+                rc |= _PDCLIB_FRW;
+                break;
+            case 'b':
+                if ( rc & _PDCLIB_FBIN ) return 0; /* Duplicates are invalid */
+                rc |= _PDCLIB_FBIN;
+                break;
+            case '\0':
+                /* End of mode */
+                return rc;
+            default:
+                /* Other than read/write or binary - invalid. */
+                return 0;
+        }
+    }
+    /* Longer than three chars - invalid. */
+    return 0;
+}
+
+#endif
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main( void )
+{
+#ifndef REGTEST
+    TESTCASE( _PDCLIB_filemode( "r" ) == _PDCLIB_FREAD );
+    TESTCASE( _PDCLIB_filemode( "w" ) == _PDCLIB_FWRITE );
+    TESTCASE( _PDCLIB_filemode( "a" ) == _PDCLIB_FAPPEND );
+    TESTCASE( _PDCLIB_filemode( "r+" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW ) );
+    TESTCASE( _PDCLIB_filemode( "w+" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW ) );
+    TESTCASE( _PDCLIB_filemode( "a+" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW ) );
+    TESTCASE( _PDCLIB_filemode( "rb" ) == ( _PDCLIB_FREAD | _PDCLIB_FBIN ) );
+    TESTCASE( _PDCLIB_filemode( "wb" ) == ( _PDCLIB_FWRITE | _PDCLIB_FBIN ) );
+    TESTCASE( _PDCLIB_filemode( "ab" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FBIN ) );
+    TESTCASE( _PDCLIB_filemode( "r+b" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( _PDCLIB_filemode( "w+b" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( _PDCLIB_filemode( "a+b" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( _PDCLIB_filemode( "rb+" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( _PDCLIB_filemode( "wb+" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+    TESTCASE( _PDCLIB_filemode( "ab+" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW | _PDCLIB_FBIN ) );
+#else
+    puts( " NOTEST fopen() test driver is PDCLib-specific." );
+#endif
+    return TEST_RESULTS;
+}
+
+#endif
diff --git a/functions/stdio/fclose.c b/functions/stdio/fclose.c
index 9ddff44..0b42330 100644
--- a/functions/stdio/fclose.c
+++ b/functions/stdio/fclose.c
@@ -29,12 +29,13 @@ int fclose( struct _PDCLIB_file_t * stream )
             _PDCLIB_close( stream->handle );
             if ( previous != NULL )
             {
-                previous->next = current->next;
+                previous->next = stream->next;
             }
             else
             {
-                _PDCLIB_filelist = current->next;
+                _PDCLIB_filelist = stream->next;
             }
+            free( stream );
             return 0;
         }
         previous = current;
diff --git a/functions/stdio/fopen.c b/functions/stdio/fopen.c
index 96fdcc1..14ce3a8 100644
--- a/functions/stdio/fopen.c
+++ b/functions/stdio/fopen.c
@@ -15,52 +15,6 @@
 /* FIXME: This approach is a possible attack vector. */
 struct _PDCLIB_file_t * _PDCLIB_filelist = NULL;
 
-/* Helper function that parses the C-style mode string passed to fopen() into
-   the PDCLib flags FREAD, FWRITE, FAPPEND, FRW (read-write) and FBIN (binary
-   mode).
-*/
-static unsigned int filemode( char const * const mode )
-{
-    int rc = 0;
-    switch ( mode[0] )
-    {
-        case 'r':
-            rc |= _PDCLIB_FREAD;
-            break;
-        case 'w':
-            rc |= _PDCLIB_FWRITE;
-            break;
-        case 'a':
-            rc |= _PDCLIB_FAPPEND;
-            break;
-        default:
-            /* Other than read, write, or append - invalid */
-            return 0;
-    }
-    for ( size_t i = 1; i < 4; ++i )
-    {
-        switch ( mode[i] )
-        {
-            case '+':
-                if ( rc & _PDCLIB_FRW ) return 0; /* Duplicates are invalid */
-                rc |= _PDCLIB_FRW;
-                break;
-            case 'b':
-                if ( rc & _PDCLIB_FBIN ) return 0; /* Duplicates are invalid */
-                rc |= _PDCLIB_FBIN;
-                break;
-            case '\0':
-                /* End of mode */
-                return rc;
-            default:
-                /* Other than read/write or binary - invalid. */
-                return 0;
-        }
-    }
-    /* Longer than three chars - invalid. */
-    return 0;
-}
-
 struct _PDCLIB_file_t * fopen( const char * _PDCLIB_restrict filename, const char * _PDCLIB_restrict mode )
 {
     struct _PDCLIB_file_t * rc;
@@ -74,7 +28,7 @@ struct _PDCLIB_file_t * fopen( const char * _PDCLIB_restrict filename, const cha
         /* no memory for another FILE */
         return NULL;
     }
-    if ( ( rc->status = filemode( mode ) ) == 0 ) goto fail; /* invalid mode */
+    if ( ( rc->status = _PDCLIB_filemode( mode ) ) == 0 ) goto fail; /* invalid mode */
     rc->handle = _PDCLIB_open( filename, rc->status );
     if ( rc->handle == _PDCLIB_NOHANDLE ) goto fail; /* OS open() failed */
     /* Adding to list of open files */
@@ -99,22 +53,6 @@ fail:
 
 int main( void )
 {
-#ifndef REGTEST
-    TESTCASE( filemode( "r" ) == _PDCLIB_FREAD );
-    TESTCASE( filemode( "w" ) == _PDCLIB_FWRITE );
-    TESTCASE( filemode( "a" ) == _PDCLIB_FAPPEND );
-    TESTCASE( filemode( "r+" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW ) );
-    TESTCASE( filemode( "w+" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW ) );
-    TESTCASE( filemode( "a+" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW ) );
-    TESTCASE( filemode( "rb" ) == ( _PDCLIB_FREAD | _PDCLIB_FBIN ) );
-    TESTCASE( filemode( "wb" ) == ( _PDCLIB_FWRITE | _PDCLIB_FBIN ) );
-    TESTCASE( filemode( "ab" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FBIN ) );
-    TESTCASE( filemode( "r+b" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW | _PDCLIB_FBIN ) );
-    TESTCASE( filemode( "w+b" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW | _PDCLIB_FBIN ) );
-    TESTCASE( filemode( "a+b" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW | _PDCLIB_FBIN ) );
-    TESTCASE( filemode( "rb+" ) == ( _PDCLIB_FREAD | _PDCLIB_FRW | _PDCLIB_FBIN ) );
-    TESTCASE( filemode( "wb+" ) == ( _PDCLIB_FWRITE | _PDCLIB_FRW | _PDCLIB_FBIN ) );
-    TESTCASE( filemode( "ab+" ) == ( _PDCLIB_FAPPEND | _PDCLIB_FRW | _PDCLIB_FBIN ) );
     TESTCASE( fopen( NULL, NULL ) == NULL );
     TESTCASE( fopen( NULL, "w" ) == NULL );
     TESTCASE( fopen( "", NULL ) == NULL );
@@ -124,9 +62,6 @@ int main( void )
     TESTCASE( fopen( "testfile", "wr" ) == NULL ); /* Illegal mode */
     TESTCASE( fopen( "testfile", "w" ) != NULL );
     system( "rm testfile" );
-#else
-    puts( " NOTEST fopen() test driver is PDCLib-specific." );
-#endif
     return TEST_RESULTS;
 }
 
diff --git a/functions/stdio/fprintf.c b/functions/stdio/fprintf.c
index 8378a95..1afe87a 100644
--- a/functions/stdio/fprintf.c
+++ b/functions/stdio/fprintf.c
@@ -24,11 +24,226 @@ int fprintf( struct _PDCLIB_file_t * _PDCLIB_restrict stream, const char * _PDCL
 #endif
 
 #ifdef TEST
+#include <limits.h>
+#include <string.h>
 #include <_PDCLIB_test.h>
 
+#define testprintf( stream, n, format, ... ) fprintf( stream, format, __VA_ARGS__ )
+
 int main( void )
 {
-    TESTCASE( NO_TESTDRIVER );
+    FILE * buffer;
+    TESTCASE( ( buffer = fopen( "testfile", "w" ) ) != NULL );
+    TESTCASE( testprintf( buffer, 100, "%hhd", CHAR_MIN ) == 4 );
+    //TESTCASE( strcmp( buffer, "-128" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhd", CHAR_MAX ) == 3 );
+    //TESTCASE( strcmp( buffer, "127" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhd", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", SHRT_MIN ) == 6 );
+    //TESTCASE( strcmp( buffer, "-32768" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", SHRT_MAX ) == 5 );
+    //TESTCASE( strcmp( buffer, "32767" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", LONG_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", LONG_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", 0l ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", LLONG_MIN ) == 20 );
+    //TESTCASE( strcmp( buffer, "-9223372036854775808" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", LLONG_MAX ) == 19 );
+    //TESTCASE( strcmp( buffer, "9223372036854775807" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", 0ll ) );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhu", UCHAR_MAX ) == 3 );
+    //TESTCASE( strcmp( buffer, "255" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhu", (unsigned char)-1 ) == 3 );
+    //TESTCASE( strcmp( buffer, "255" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hu", USHRT_MAX ) == 5 );
+    //TESTCASE( strcmp( buffer, "65535" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hu", (unsigned short)-1 ) == 5 );
+    //TESTCASE( strcmp( buffer, "65535" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lu", ULONG_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lu", -1ul ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%llu", ULLONG_MAX ) == 20 );
+    //TESTCASE( strcmp( buffer, "18446744073709551615" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%llu", -1ull ) == 20 );
+    //TESTCASE( strcmp( buffer, "18446744073709551615" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%X", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "FFFFFFFF" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#X", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "0XFFFFFFFF" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%x", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "ffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#x", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%o", UINT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "37777777777" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#o", -1u ) == 12 );
+    //TESTCASE( strcmp( buffer, "037777777777" ) == 0 );
+    /* TODO: This test case is broken, doesn't test what it was intended to. */
+    TESTCASE( testprintf( buffer, 100, "%.0#o", 0 ) == 5 );
+    //TESTCASE( strcmp( buffer, "%.0#o" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", 0 ) == 2 );
+    //TESTCASE( strcmp( buffer, "+0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, " 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", 0 ) == 2 );
+    //TESTCASE( strcmp( buffer, " 0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%9d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%9d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%10d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%10d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%11d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%11d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, " 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%12d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, " -2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%12d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "  2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-9d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-9d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-10d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-10d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-11d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-11d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "2147483647 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-12d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-2147483648 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-12d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "2147483647  " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%09d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%09d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%010d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%010d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%011d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%011d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "02147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%012d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-02147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%012d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "002147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-09d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-09d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-010d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-010d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-011d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-011d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "2147483647 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-012d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-2147483648 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-012d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "2147483647  " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%030.20d", INT_MAX ) == 30 );
+    //TESTCASE( strcmp( buffer, "          00000000002147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%.6x", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "ffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#6.3x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#3.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%.6d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%6.3d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%3.6d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#0.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#06.3x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#03.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#0.6d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#06.3d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#03.6d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+6.3d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+3.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+0.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+06.3d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+03.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "- %d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "- 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "- %d %% %d", INT_MAX, INT_MIN ) == 26 );
+    //TESTCASE( strcmp( buffer, "- 2147483647 % -2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%c", 'x' ) == 1 );
+    //TESTCASE( strcmp( buffer, "x" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%s", "abcdef" ) == 6 );
+    //TESTCASE( strcmp( buffer, "abcdef" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%p", (void *)0xdeadbeef ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xdeadbeef" ) == 0 );
+    {
+        int val1, val2;
+        TESTCASE( testprintf( buffer, 100, "123456%n789%n", &val1, &val2 ) == 9 );
+        //TESTCASE( strcmp( buffer, "123456789" ) == 0 );
+        TESTCASE( val1 == 6 );
+        TESTCASE( val2 == 9 );
+    }
+    TESTCASE( fclose( buffer ) == 0 );
+    char readbuffer[1000];
+    TESTCASE( ( buffer = fopen( "testfile", "r" ) ) != NULL );
+    TESTCASE( fread( readbuffer, 1, 1000, buffer ) == 985 );
+    TESTCASE( fclose( buffer ) == 0 );
+    TESTCASE( memcmp( readbuffer, "-1281270-32768327670-214748364821474836470-214748364821474836470-922337203685477580892233720368547758070255255655356553542949672954294967295429496729542949672951844674407370955161518446744073709551615FFFFFFFF0XFFFFFFFFffffffff0xffffffff37777777777037777777777%.0#o-2147483648+2147483647+042949672954294967295-2147483648 2147483647 042949672954294967295-21474836482147483647-21474836482147483647-2147483648 2147483647 -2147483648  2147483647-21474836482147483647-21474836482147483647-21474836482147483647 -2147483648 2147483647  -21474836482147483647-21474836482147483647-214748364802147483647-02147483648002147483647-21474836482147483647-21474836482147483647-21474836482147483647 -2147483648 2147483647            00000000002147483647ffffffff0xffffffff0xffffffff-2147483648-2147483648-21474836480xffffffff0xffffffff0xffffffff214748364721474836472147483647+2147483647+2147483647+2147483647+2147483647+2147483647+2147483647- 2147483647- 2147483647 % -2147483648xabcdef0xdeadbeef123456789", 985 ) == 0 );
     return TEST_RESULTS;
 }
 
diff --git a/functions/stdio/freopen.c b/functions/stdio/freopen.c
new file mode 100644
index 0000000..be4b95e
--- /dev/null
+++ b/functions/stdio/freopen.c
@@ -0,0 +1,55 @@
+/* $Id$ */
+
+/* freopen( const char *, const char * )
+
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <stdio.h>
+
+#ifndef REGTEST
+
+#include <_PDCLIB_glue.h>
+#include <stdlib.h>
+
+/* Close any file currently associated with the given stream. Open the file
+   identified by the given filename with the given mode (equivalent to fopen()),
+   and associate it with the given stream. If filename is a NULL pointer,
+   attempt to change the mode of the given stream.
+   This implementation allows the following mode changes: TODO
+   (Primary use of this function is to redirect stdin, stdout, and stderr.)
+*/
+
+struct _PDCLIB_file_t * freopen( const char * _PDCLIB_restrict filename, const char * _PDCLIB_restrict mode, struct _PDCLIB_file_t * stream )
+{
+    /* FIXME: This is ad-hoc (to make the vprintf() testdriver work), and must be checked. */
+    /* FIXME: If filename is NULL, change mode. */
+    if ( filename == NULL ) return NULL;
+    if ( stream->status & _PDCLIB_WROTELAST ) fflush( stream );
+    if ( stream->status & _PDCLIB_LIBBUFFER ) free( stream->buffer );
+    _PDCLIB_close( stream->handle );
+    clearerr( stream );
+    if ( ( mode == NULL ) || ( filename[0] == '\0' ) ) return NULL;
+    if ( ( stream->status = _PDCLIB_filemode( mode ) ) == 0 ) return NULL;
+    stream->handle = _PDCLIB_open( filename, stream->status );
+    if ( ( stream->buffer = malloc( BUFSIZ ) ) == NULL ) return NULL;
+    stream->bufsize = BUFSIZ;
+    stream->bufidx = 0;
+    stream->status |= ( _PDCLIB_LIBBUFFER | _PDCLIB_VIRGINSTR );
+    /* TODO: Setting mbstate */
+    return stream;
+}
+
+#endif
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main( void )
+{
+    TESTCASE( NO_TESTDRIVER );
+    return TEST_RESULTS;
+}
+
+#endif
diff --git a/functions/stdio/vfprintf.c b/functions/stdio/vfprintf.c
index 9a9a950..8c8c022 100644
--- a/functions/stdio/vfprintf.c
+++ b/functions/stdio/vfprintf.c
@@ -39,9 +39,11 @@ int vfprintf( struct _PDCLIB_file_t * _PDCLIB_restrict stream, const char * _PDC
 
 #ifdef TEST
 #include <stdlib.h>
+#include <limits.h>
+#include <string.h>
 #include <_PDCLIB_test.h>
 
-static int testprintf( FILE * stream, const char * format, ... )
+static int testprintf( FILE * stream, size_t n, const char * format, ... )
 {
     int i;
     va_list arg;
@@ -53,11 +55,218 @@ static int testprintf( FILE * stream, const char * format, ... )
 
 int main( void )
 {
-    FILE * fh;
-    TESTCASE( ( fh = fopen( "testfile", "w" ) ) != NULL );
-    TESTCASE( testprintf( fh, "Hallo\n" ) == 6 );
-    TESTCASE( fclose( fh ) == 0 );
-    /* FIXME: Testfile doesn't exist... */
+    FILE * buffer;
+    TESTCASE( ( buffer = fopen( "testfile", "w" ) ) != NULL );
+    TESTCASE( testprintf( buffer, 100, "%hhd", CHAR_MIN ) == 4 );
+    //TESTCASE( strcmp( buffer, "-128" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhd", CHAR_MAX ) == 3 );
+    //TESTCASE( strcmp( buffer, "127" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhd", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", SHRT_MIN ) == 6 );
+    //TESTCASE( strcmp( buffer, "-32768" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", SHRT_MAX ) == 5 );
+    //TESTCASE( strcmp( buffer, "32767" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", LONG_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", LONG_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", 0l ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", LLONG_MIN ) == 20 );
+    //TESTCASE( strcmp( buffer, "-9223372036854775808" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", LLONG_MAX ) == 19 );
+    //TESTCASE( strcmp( buffer, "9223372036854775807" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", 0ll ) );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhu", UCHAR_MAX ) == 3 );
+    //TESTCASE( strcmp( buffer, "255" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhu", (unsigned char)-1 ) == 3 );
+    //TESTCASE( strcmp( buffer, "255" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hu", USHRT_MAX ) == 5 );
+    //TESTCASE( strcmp( buffer, "65535" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hu", (unsigned short)-1 ) == 5 );
+    //TESTCASE( strcmp( buffer, "65535" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lu", ULONG_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lu", -1ul ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%llu", ULLONG_MAX ) == 20 );
+    //TESTCASE( strcmp( buffer, "18446744073709551615" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%llu", -1ull ) == 20 );
+    //TESTCASE( strcmp( buffer, "18446744073709551615" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%X", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "FFFFFFFF" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#X", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "0XFFFFFFFF" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%x", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "ffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#x", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%o", UINT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "37777777777" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#o", -1u ) == 12 );
+    //TESTCASE( strcmp( buffer, "037777777777" ) == 0 );
+    /* TODO: This test case is broken, doesn't test what it was intended to. */
+    TESTCASE( testprintf( buffer, 100, "%.0#o", 0 ) == 5 );
+    //TESTCASE( strcmp( buffer, "%.0#o" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", 0 ) == 2 );
+    //TESTCASE( strcmp( buffer, "+0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, " 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", 0 ) == 2 );
+    //TESTCASE( strcmp( buffer, " 0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%9d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%9d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%10d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%10d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%11d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%11d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, " 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%12d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, " -2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%12d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "  2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-9d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-9d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-10d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-10d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-11d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-11d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "2147483647 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-12d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-2147483648 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-12d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "2147483647  " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%09d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%09d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%010d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%010d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%011d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%011d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "02147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%012d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-02147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%012d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "002147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-09d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-09d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-010d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-010d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-011d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-011d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "2147483647 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-012d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-2147483648 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-012d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "2147483647  " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%030.20d", INT_MAX ) == 30 );
+    //TESTCASE( strcmp( buffer, "          00000000002147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%.6x", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "ffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#6.3x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#3.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%.6d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%6.3d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%3.6d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#0.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#06.3x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#03.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#0.6d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#06.3d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#03.6d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+6.3d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+3.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+0.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+06.3d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+03.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "- %d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "- 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "- %d %% %d", INT_MAX, INT_MIN ) == 26 );
+    //TESTCASE( strcmp( buffer, "- 2147483647 % -2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%c", 'x' ) == 1 );
+    //TESTCASE( strcmp( buffer, "x" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%s", "abcdef" ) == 6 );
+    //TESTCASE( strcmp( buffer, "abcdef" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%p", (void *)0xdeadbeef ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xdeadbeef" ) == 0 );
+    {
+        int val1, val2;
+        TESTCASE( testprintf( buffer, 100, "123456%n789%n", &val1, &val2 ) == 9 );
+        //TESTCASE( strcmp( buffer, "123456789" ) == 0 );
+        TESTCASE( val1 == 6 );
+        TESTCASE( val2 == 9 );
+    }
+    TESTCASE( fclose( buffer ) == 0 );
+    char readbuffer[1000];
+    TESTCASE( ( buffer = fopen( "testfile", "r" ) ) != NULL );
+    TESTCASE( fread( readbuffer, 1, 1000, buffer ) == 985 );
+    TESTCASE( fclose( buffer ) == 0 );
+    TESTCASE( memcmp( readbuffer, "-1281270-32768327670-214748364821474836470-214748364821474836470-922337203685477580892233720368547758070255255655356553542949672954294967295429496729542949672951844674407370955161518446744073709551615FFFFFFFF0XFFFFFFFFffffffff0xffffffff37777777777037777777777%.0#o-2147483648+2147483647+042949672954294967295-2147483648 2147483647 042949672954294967295-21474836482147483647-21474836482147483647-2147483648 2147483647 -2147483648  2147483647-21474836482147483647-21474836482147483647-21474836482147483647 -2147483648 2147483647  -21474836482147483647-21474836482147483647-214748364802147483647-02147483648002147483647-21474836482147483647-21474836482147483647-21474836482147483647 -2147483648 2147483647            00000000002147483647ffffffff0xffffffff0xffffffff-2147483648-2147483648-21474836480xffffffff0xffffffff0xffffffff214748364721474836472147483647+2147483647+2147483647+2147483647+2147483647+2147483647+2147483647- 2147483647- 2147483647 % -2147483648xabcdef0xdeadbeef123456789", 985 ) == 0 );
     return TEST_RESULTS;
 }
 
diff --git a/functions/stdio/vprintf.c b/functions/stdio/vprintf.c
index a8ca45f..d7ad502 100644
--- a/functions/stdio/vprintf.c
+++ b/functions/stdio/vprintf.c
@@ -19,11 +19,234 @@ int vprintf( const char * _PDCLIB_restrict format, _PDCLIB_va_list arg )
 #endif
 
 #ifdef TEST
+#include <limits.h>
+#include <string.h>
 #include <_PDCLIB_test.h>
 
+static int testprintf( FILE * stream, size_t n, const char * format, ... )
+{
+    int i;
+    va_list arg;
+    va_start( arg, format );
+    i = vprintf( format, arg );
+    va_end( arg );
+    return i;
+}
+
 int main( void )
 {
-    TESTCASE( NO_TESTDRIVER );
+    FILE * buffer;
+    TESTCASE( ( buffer = freopen( "testfile", "w", stdout ) ) != NULL );
+    TESTCASE( testprintf( buffer, 100, "%hhd", CHAR_MIN ) == 4 );
+    //TESTCASE( strcmp( buffer, "-128" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhd", CHAR_MAX ) == 3 );
+    //TESTCASE( strcmp( buffer, "127" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhd", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", SHRT_MIN ) == 6 );
+    //TESTCASE( strcmp( buffer, "-32768" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", SHRT_MAX ) == 5 );
+    //TESTCASE( strcmp( buffer, "32767" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hd", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%d", 0 ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", LONG_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", LONG_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%ld", 0l ) == 1 );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", LLONG_MIN ) == 20 );
+    //TESTCASE( strcmp( buffer, "-9223372036854775808" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", LLONG_MAX ) == 19 );
+    //TESTCASE( strcmp( buffer, "9223372036854775807" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lld", 0ll ) );
+    //TESTCASE( strcmp( buffer, "0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhu", UCHAR_MAX ) == 3 );
+    //TESTCASE( strcmp( buffer, "255" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hhu", (unsigned char)-1 ) == 3 );
+    //TESTCASE( strcmp( buffer, "255" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hu", USHRT_MAX ) == 5 );
+    //TESTCASE( strcmp( buffer, "65535" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%hu", (unsigned short)-1 ) == 5 );
+    //TESTCASE( strcmp( buffer, "65535" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lu", ULONG_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%lu", -1ul ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%llu", ULLONG_MAX ) == 20 );
+    //TESTCASE( strcmp( buffer, "18446744073709551615" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%llu", -1ull ) == 20 );
+    //TESTCASE( strcmp( buffer, "18446744073709551615" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%X", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "FFFFFFFF" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#X", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "0XFFFFFFFF" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%x", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "ffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#x", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%o", UINT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "37777777777" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#o", -1u ) == 12 );
+    //TESTCASE( strcmp( buffer, "037777777777" ) == 0 );
+    /* TODO: This test case is broken, doesn't test what it was intended to. */
+    TESTCASE( testprintf( buffer, 100, "%.0#o", 0 ) == 5 );
+    //TESTCASE( strcmp( buffer, "%.0#o" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+d", 0 ) == 2 );
+    //TESTCASE( strcmp( buffer, "+0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, " 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% d", 0 ) == 2 );
+    //TESTCASE( strcmp( buffer, " 0" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% u", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "% u", -1u ) == 10 );
+    //TESTCASE( strcmp( buffer, "4294967295" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%9d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%9d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%10d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%10d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%11d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%11d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, " 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%12d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, " -2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%12d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "  2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-9d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-9d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-10d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-10d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-11d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-11d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "2147483647 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-12d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-2147483648 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-12d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "2147483647  " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%09d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%09d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%010d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%010d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%011d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%011d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "02147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%012d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-02147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%012d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "002147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-09d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-09d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-010d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-010d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-011d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-011d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "2147483647 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-012d", INT_MIN ) == 12 );
+    //TESTCASE( strcmp( buffer, "-2147483648 " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%-012d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "2147483647  " ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%030.20d", INT_MAX ) == 30 );
+    //TESTCASE( strcmp( buffer, "          00000000002147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%.6x", UINT_MAX ) == 8 );
+    //TESTCASE( strcmp( buffer, "ffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#6.3x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#3.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%.6d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%6.3d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%3.6d", INT_MIN ) == 11 );
+    //TESTCASE( strcmp( buffer, "-2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#0.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#06.3x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#03.6x", UINT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xffffffff" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#0.6d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#06.3d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#03.6d", INT_MAX ) == 10 );
+    //TESTCASE( strcmp( buffer, "2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+6.3d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%#+3.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+0.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+06.3d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%+03.6d", INT_MAX ) == 11 );
+    //TESTCASE( strcmp( buffer, "+2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "- %d", INT_MAX ) == 12 );
+    //TESTCASE( strcmp( buffer, "- 2147483647" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "- %d %% %d", INT_MAX, INT_MIN ) == 26 );
+    //TESTCASE( strcmp( buffer, "- 2147483647 % -2147483648" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%c", 'x' ) == 1 );
+    //TESTCASE( strcmp( buffer, "x" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%s", "abcdef" ) == 6 );
+    //TESTCASE( strcmp( buffer, "abcdef" ) == 0 );
+    TESTCASE( testprintf( buffer, 100, "%p", (void *)0xdeadbeef ) == 10 );
+    //TESTCASE( strcmp( buffer, "0xdeadbeef" ) == 0 );
+    {
+        int val1, val2;
+        TESTCASE( testprintf( buffer, 100, "123456%n789%n", &val1, &val2 ) == 9 );
+        //TESTCASE( strcmp( buffer, "123456789" ) == 0 );
+        TESTCASE( val1 == 6 );
+        TESTCASE( val2 == 9 );
+    }
+    TESTCASE( fclose( buffer ) == 0 );
+    char readbuffer[1000];
+    TESTCASE( ( buffer = fopen( "testfile", "r" ) ) != NULL );
+    TESTCASE( fread( readbuffer, 1, 1000, buffer ) == 985 );
+    TESTCASE( fclose( buffer ) == 0 );
+    TESTCASE( memcmp( readbuffer, "-1281270-32768327670-214748364821474836470-214748364821474836470-922337203685477580892233720368547758070255255655356553542949672954294967295429496729542949672951844674407370955161518446744073709551615FFFFFFFF0XFFFFFFFFffffffff0xffffffff37777777777037777777777%.0#o-2147483648+2147483647+042949672954294967295-2147483648 2147483647 042949672954294967295-21474836482147483647-21474836482147483647-2147483648 2147483647 -2147483648  2147483647-21474836482147483647-21474836482147483647-21474836482147483647 -2147483648 2147483647  -21474836482147483647-21474836482147483647-214748364802147483647-02147483648002147483647-21474836482147483647-21474836482147483647-21474836482147483647 -2147483648 2147483647            00000000002147483647ffffffff0xffffffff0xffffffff-2147483648-2147483648-21474836480xffffffff0xffffffff0xffffffff214748364721474836472147483647+2147483647+2147483647+2147483647+2147483647+2147483647+2147483647- 2147483647- 2147483647 % -2147483648xabcdef0xdeadbeef123456789", 985 ) == 0 );
     return TEST_RESULTS;
 }
 
diff --git a/internals/_PDCLIB_int.h b/internals/_PDCLIB_int.h
index 1c89ae0..0ce2c99 100644
--- a/internals/_PDCLIB_int.h
+++ b/internals/_PDCLIB_int.h
@@ -344,3 +344,6 @@ extern char _PDCLIB_Xdigits[];
    Returns a pointer to the first character not parsed as conversion specifier.
 */
 const char * _PDCLIB_print( const char * spec, struct _PDCLIB_status_t * status );
+
+/* Parsing any fopen() style filemode string into a number of flags. */
+unsigned int _PDCLIB_filemode( const char * mode );