diff --git a/src/kernel/libroot/posix/stdlib/atoi.c b/src/kernel/libroot/posix/stdlib/atoi.c
index 038c4c08fc..66eac93af0 100644
--- a/src/kernel/libroot/posix/stdlib/atoi.c
+++ b/src/kernel/libroot/posix/stdlib/atoi.c
@@ -1,86 +1,54 @@
-/* 
-** Copyright 2001, Travis Geiselbrecht. All rights reserved.
-** Distributed under the terms of the NewOS License.
-*/
+/*
+ *  Copyright (c) 2002, OpenBeOS Project.
+ *  All rights reserved.
+ *  Distributed under the terms of the OpenBeOS license.
+ *
+ *
+ *  atoi.c:
+ *  implements the standard C library functions:
+ *    atoi, atoui, atol, atoul, atoll
+ *  (these are all just wrappers around calls to the strto[u]l[l] functions)
+ *
+ *
+ *  Author(s):
+ *  Daniel Reinhold (danielre@users.sf.net)
+ *
+ */
+ 
 #include <stdlib.h>
-#include <ctype.h>
 
-static int hexval(char c)
+
+int
+atoi(const char *num)
 {
-	if (c >= '0' && c <= '9')
-		return c - '0';
-	else if (c >= 'a' && c <= 'f')
-		return c - 'a' + 10;
-	else if (c >= 'A' && c <= 'F')
-		return c - 'A' + 10;
-		
-	return 0;
+	return (int) strtol(num, NULL, 10);
 }
 
-int atoi(const char *num)
-{
-	int value = 0;
-	if (num[0] == '0' && num[1] == 'x') {
-		// hex
-		num += 2;
-		while (*num && isxdigit(*num))
-			value = value * 16 + hexval(*num++);
-	} else {
-		// decimal
-		while (*num && isdigit(*num))
-			value = value * 10 + *num++  - '0';
-	}
 
-	return value;
+unsigned int
+atoui(const char *num)
+{
+	return (unsigned int) strtoul(num, NULL, 10);
 }
 
-unsigned int atoui(const char *num)
-{
-	int value = 0;
-	if (num[0] == '0' && num[1] == 'x') {
-		// hex
-		num += 2;
-		while (*num && isxdigit(*num))
-			value = value * 16 + hexval(*num++);
-	} else {
-		// decimal
-		while (*num && isdigit(*num))
-			value = value * 10 + *num++  - '0';
-	}
 
-	return value;
+long
+atol(const char *num)
+{
+	return strtol(num, NULL, 10);
 }
 
-long atol(const char *num)
-{
-	int value = 0;
-	if (num[0] == '0' && num[1] == 'x') {
-		// hex
-		num += 2;
-		while (*num && isxdigit(*num))
-			value = value * 16 + hexval(*num++);
-	} else {
-		// decimal
-		while (*num && isdigit(*num))
-			value = value * 10 + *num++  - '0';
-	}
 
-	return value;
+unsigned long
+atoul(const char *num)
+{
+	return strtoul(num, NULL, 10);
 }
 
-unsigned long atoul(const char *num)
-{
-	int value = 0;
-	if (num[0] == '0' && num[1] == 'x') {
-		// hex
-		num += 2;
-		while (*num && isxdigit(*num))
-			value = value * 16 + hexval(*num++);
-	} else {
-		// decimal
-		while (*num && isdigit(*num))
-			value = value * 10 + *num++  - '0';
-	}
 
-	return value;
+long long int
+atoll(const char *num)
+{
+	return strtoll(num, NULL, 10);
 }
+