diff --git a/stdio/printf.c b/stdio/printf.c
index b9b31b2..8551b4d 100755
--- a/stdio/printf.c
+++ b/stdio/printf.c
@@ -3,6 +3,7 @@
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
+#include <errno.h>
 
 static bool print(const char * str, size_t len) {
   const unsigned char * bytes = (const unsigned char *) str;
@@ -16,6 +17,174 @@ static bool print(const char * str, size_t len) {
   return true;
 }
 
+static bool print_oct(unsigned int strint) {
+  int i = strint, j = 10;
+  char str[11] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+  
+  while(j >= 0 && i > 0) {
+    switch(i % 010) {
+    case 0: str[j] = '0'; break;
+    case 1: str[j] = '1'; break;
+    case 2: str[j] = '2'; break;
+    case 3: str[j] = '3'; break;
+    case 4: str[j] = '4'; break;
+    case 5: str[j] = '5'; break;
+    case 6: str[j] = '6'; break;
+    case 7: str[j] = '7'; break;
+    default: return false;
+    }
+    i /= 010;
+    j--;
+  }
+  for(i = 0; str[i] == '\0'; i++) {}
+
+  return print(str+i, 11-i);
+}
+
+static bool print_ptr(void * ptrstr) {
+  int i = (int) ptrstr, j = 9;
+  char str[10] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+  
+  while(j >= 2 && i > 0) {
+    switch(i % 0x10) {
+    case 0: str[j] = '0'; break;
+    case 1: str[j] = '1'; break;
+    case 2: str[j] = '2'; break;
+    case 3: str[j] = '3'; break;
+    case 4: str[j] = '4'; break;
+    case 5: str[j] = '5'; break;
+    case 6: str[j] = '6'; break;
+    case 7: str[j] = '7'; break;
+    case 8: str[j] = '8'; break;
+    case 9: str[j] = '9'; break;
+    case 0xA: str[j] = 'A'; break;
+    case 0xB: str[j] = 'B'; break;
+    case 0xC: str[j] = 'C'; break;
+    case 0xD: str[j] = 'D'; break;
+    case 0xE: str[j] = 'E'; break;
+    case 0xF: str[j] = 'F'; break;
+    default: return false;
+    }
+    i /= 0x10;
+    j--;
+  }
+  for(i = 0; str[i] == '\0'; i++) {}
+
+  i--;
+  str[i] = 'x';
+  i--;
+  str[i] = '0';
+
+  return print(str+i, 10-i);
+}
+
+static bool print_caphex(unsigned int strint) {
+  int i = strint, j = 7;
+  char str[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
+  
+  while(j >= 0 && i > 0) {
+    switch(i % 0x10) {
+    case 0: str[j] = '0'; break;
+    case 1: str[j] = '1'; break;
+    case 2: str[j] = '2'; break;
+    case 3: str[j] = '3'; break;
+    case 4: str[j] = '4'; break;
+    case 5: str[j] = '5'; break;
+    case 6: str[j] = '6'; break;
+    case 7: str[j] = '7'; break;
+    case 8: str[j] = '8'; break;
+    case 9: str[j] = '9'; break;
+    case 0xA: str[j] = 'A'; break;
+    case 0xB: str[j] = 'B'; break;
+    case 0xC: str[j] = 'C'; break;
+    case 0xD: str[j] = 'D'; break;
+    case 0xE: str[j] = 'E'; break;
+    case 0xF: str[j] = 'F'; break;
+    default: return false;
+    }
+    i /= 0x10;
+    j--;
+  }
+  for(i = 0; str[i] == '\0'; i++) {}
+
+  return print(str+i, 8-i);
+}
+
+static bool print_hex(unsigned int strint) {
+  int i = strint, j = 7;
+  char str[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
+  
+  while(j >= 0 && i > 0) {
+    switch(i % 0x10) {
+    case 0: str[j] = '0'; break;
+    case 1: str[j] = '1'; break;
+    case 2: str[j] = '2'; break;
+    case 3: str[j] = '3'; break;
+    case 4: str[j] = '4'; break;
+    case 5: str[j] = '5'; break;
+    case 6: str[j] = '6'; break;
+    case 7: str[j] = '7'; break;
+    case 8: str[j] = '8'; break;
+    case 9: str[j] = '9'; break;
+    case 0xA: str[j] = 'a'; break;
+    case 0xB: str[j] = 'b'; break;
+    case 0xC: str[j] = 'c'; break;
+    case 0xD: str[j] = 'd'; break;
+    case 0xE: str[j] = 'e'; break;
+    case 0xF: str[j] = 'f'; break;
+    default: return false;
+    }
+    i /= 0x10;
+    j--;
+  }
+  for(i = 0; str[i] == '\0'; i++) {}
+
+  return print(str+i, 8-i);
+}
+
+static bool print_int(int strint) {
+  int i = strint, j = 10;
+  char str[11] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+
+  if(i < 0) {
+    i = -i;
+  }
+  
+  while(j > 0 && i > 0) {
+    switch(i % 10) {
+    case 0: str[j] = '0'; break;
+    case 1: str[j] = '1'; break;
+    case 2: str[j] = '2'; break;
+    case 3: str[j] = '3'; break;
+    case 4: str[j] = '4'; break;
+    case 5: str[j] = '5'; break;
+    case 6: str[j] = '6'; break;
+    case 7: str[j] = '7'; break;
+    case 8: str[j] = '8'; break;
+    case 9: str[j] = '9'; break;
+    default: return false;
+    }
+    i /= 10;
+    j--;
+  }
+  for(i = 0; str[i] == '\0'; i++) {}
+
+  if(strint < 0) {
+    i--;
+    str[i] = '-';
+  }
+
+  return print(str+i, 11-i);
+}
+
+static bool print_uint(unsigned int strint) {
+  int i = strint;
+  if(i < 0) {
+    i = -i;
+  }
+  return print_int(i);
+}
+
 int printf(const char * restrict format, ...) {
   va_list parameters;
   va_start(parameters, format);
@@ -37,7 +206,7 @@ int printf(const char * restrict format, ...) {
       }
 
       if(maxrem < amount) {
-	/* TODO: Set errno to EOVERFLOW after implementing errno.h */
+	errno = EOVERFLOW;
 	return -1;
       }
 
@@ -58,7 +227,7 @@ int printf(const char * restrict format, ...) {
       char c = (char) va_arg(parameters, int);
 
       if(!maxrem) {
-	/* TODO: Set errno to EOVERFLOW after implementing errno.h */
+        errno = EOVERFLOW;
 	return -1;
       }
 
@@ -74,7 +243,7 @@ int printf(const char * restrict format, ...) {
       size_t len = strlen(str);
 
       if(maxrem < len) {
-	/* TODO: Set errno to EOVERFLOW after implementing errno.h */
+        errno = EOVERFLOW;
 	return -1;
       }
 
@@ -84,12 +253,130 @@ int printf(const char * restrict format, ...) {
 
       written += len;
     }
+    else if(*format == 'd' || *format == 'i') {
+      format++;
+      int i = (int) va_arg(parameters, int);
+
+      if(!maxrem) {
+	errno = EOVERFLOW;
+	return -1;
+      }
+
+      if(!print_int(i)) {
+	return -1;
+      }
+
+      written += 11;
+    }
+    else if(*format == 'u') {
+      format++;
+      int i = (int) va_arg(parameters, int);
+
+      if(!maxrem) {
+	errno = EOVERFLOW;
+	return -1;
+      }
+
+      if(!print_uint(i)) {
+	return -1;
+      }
+
+      written += 10;
+    }
+    else if(*format == 'o') {
+      format++;
+      int i = (int) va_arg(parameters, int);
+
+      if(!maxrem) {
+	errno = EOVERFLOW;
+	return -1;
+      }
+
+      if(!print_oct(i)) {
+	return -1;
+      }
+
+      written += 11;
+    }
+    else if(*format == 'x') {
+      format++;
+      int i = (int) va_arg(parameters, int);
+
+      if(!maxrem) {
+	errno = EOVERFLOW;
+	return -1;
+      }
+
+      if(!print_hex(i)) {
+	return -1;
+      }
+
+      written += 10;
+    }
+    else if(*format == 'X') {
+      format++;
+      int i = (int) va_arg(parameters, int);
+
+      if(!maxrem) {
+	errno = EOVERFLOW;
+	return -1;
+      }
+
+      if(!print_caphex(i)) {
+	return -1;
+      }
+
+      written += 8;
+    }
+    else if(*format == 'p') {
+      format++;
+      void * ptr = (void *) va_arg(parameters, void *);
+
+      if(!maxrem) {
+	errno = EOVERFLOW;
+	return -1;
+      }
+
+      if(!print_ptr(ptr)) {
+	return -1;
+      }
+
+      /* This is gonna need a change on 64-bit systems. */
+      written += 10;
+    }else if(*format == 'n') {
+      format++;
+
+      if(!maxrem) {
+	errno = EOVERFLOW;
+	return -1;
+      }
+
+      if(!print_int(written)) {
+	return -1;
+      }
+
+      written += 11;
+    }
+    else if(*format == '%') {
+      format++;
+      
+      if(!maxrem) {
+	errno = EOVERFLOW;
+	return -1;
+      }
+
+      if(!print("%", 1)) {
+	return -1;
+      }
+
+      written++;
+    }
     else {
       format = format_begun_at;
       size_t len = strlen(format);
 
       if(maxrem < len) {
-	/* TODO: Set errno to EOVERFLOW after implementing errno.h */
+        errno = EOVERFLOW;
 	return -1;
       }