diff --git a/src/chmod/chmod.rs b/src/chmod/chmod.rs
index 4517e0e71..74b3e740e 100644
--- a/src/chmod/chmod.rs
+++ b/src/chmod/chmod.rs
@@ -21,7 +21,7 @@ extern crate regex;
 
 use std::io::fs;
 use std::io::fs::PathExtensions;
-use std::u64;
+use std::num::from_str_radix;
 use regex::Regex;
 
 #[path = "../common/util.rs"]
@@ -273,7 +273,7 @@ fn chmod_file(file: &Path, name: &str, changes: bool, quiet: bool, verbose: bool
                         '+' | '-' | '=' => (ch, change.slice_from(1)),
                         _ => ('=', change)
                     };
-                    let mode = u64::parse_bytes(slice.as_bytes(), 8).unwrap();  // already verified
+                    let mode = from_str_radix::<u64>(slice, 8).unwrap();  // already verified
                     match action {
                         '+' => fperm |= mode,
                         '-' => fperm &= !mode,
diff --git a/src/du/du.rs b/src/du/du.rs
index 14f8915a7..d6c49fedc 100644
--- a/src/du/du.rs
+++ b/src/du/du.rs
@@ -20,6 +20,7 @@ use std::io::{stderr, fs, FileStat, TypeDirectory};
 use std::option::Option;
 use std::path::Path;
 use std::sync::{Arc, Future};
+use std::str::from_utf8;
 use time::Timespec;
 
 #[path = "../common/util.rs"]
@@ -244,7 +245,7 @@ ers of 1000).",
                     letters.push(c);
                 }
             }
-            let number = std::uint::parse_bytes(numbers.as_slice(), 10).unwrap();
+            let number = from_utf8(numbers.as_slice()).and_then(from_str::<uint>).unwrap();
             let multiple = match String::from_chars(letters.as_slice()).as_slice() {
                 "K" => 1024, "M" => 1024 * 1024, "G" => 1024 * 1024 * 1024,
                 "T" => 1024 * 1024 * 1024 * 1024, "P" => 1024 * 1024 * 1024 * 1024 * 1024,
diff --git a/src/echo/echo.rs b/src/echo/echo.rs
index 7d19c7aff..545970cbe 100644
--- a/src/echo/echo.rs
+++ b/src/echo/echo.rs
@@ -14,7 +14,8 @@ extern crate getopts;
 extern crate libc;
 
 use std::io::{print, println};
-use std::uint;
+use std::num::from_str_radix;
+use std::str::from_utf8;
 
 #[path = "../common/util.rs"]
 mod util;
@@ -31,7 +32,7 @@ struct EchoOptions {
 
 #[inline(always)]
 fn to_char(bytes: &Vec<u8>, base: uint) -> char {
-    uint::parse_bytes(bytes.as_slice(), base).unwrap() as u8 as char
+    from_str_radix::<uint>(from_utf8(bytes.as_slice()).unwrap(), base).unwrap() as u8 as char
 }
 
 #[inline(always)]
diff --git a/src/factor/factor.rs b/src/factor/factor.rs
index 02e8190ee..e5399fdb1 100644
--- a/src/factor/factor.rs
+++ b/src/factor/factor.rs
@@ -13,7 +13,6 @@
 extern crate getopts;
 extern crate libc;
 
-use std::u64;
 use std::vec::{Vec};
 use std::io::{stdin};
 
@@ -56,7 +55,7 @@ fn print_factors(num: u64) {
 }
 
 fn print_factors_str(num_str: &str) {
-    let num = match u64::parse_bytes(num_str.as_bytes(), 10) {
+    let num = match from_str(num_str) {
         Some(x) => x,
         None => { crash!(1, "{} not a number", num_str); }
     };
diff --git a/src/fold/fold.rs b/src/fold/fold.rs
index 9cf46a924..cb9a9fce9 100644
--- a/src/fold/fold.rs
+++ b/src/fold/fold.rs
@@ -17,7 +17,6 @@ extern crate libc;
 use std::io;
 use std::io::fs::File;
 use std::io::BufferedReader;
-use std::uint;
 
 #[path = "../common/util.rs"]
 mod util;
@@ -64,7 +63,7 @@ pub fn uumain(args: Vec<String>) -> int {
                 }
             };
         let width = match poss_width {
-            Some(inp_width) => match uint::parse_bytes(inp_width.as_bytes(), 10) {
+            Some(inp_width) => match from_str(inp_width.as_slice()) {
                 Some(width) => width,
                 None => crash!(1, "illegal width value (\"{}\")", inp_width)
             },
diff --git a/src/mkdir/mkdir.rs b/src/mkdir/mkdir.rs
index 559a36c99..b9cc0aac0 100644
--- a/src/mkdir/mkdir.rs
+++ b/src/mkdir/mkdir.rs
@@ -16,7 +16,7 @@ extern crate libc;
 
 use std::io::fs::{mod, PathExtensions};
 use std::io::FilePermission;
-use std::num::strconv;
+use std::num::from_str_radix;
 
 #[path = "../common/util.rs"]
 mod util;
@@ -64,9 +64,7 @@ pub fn uumain(args: Vec<String>) -> int {
     let mode_match = matches.opts_str(&["mode".to_string()]);
     let mode: FilePermission = if mode_match.is_some() {
         let m = mode_match.unwrap();
-        let res: Option<u32> = strconv::from_str_common(m.as_slice(), 8, false, false, false,
-                                                        strconv::ExpNone,
-                                                        false, false);
+        let res: Option<u32> = from_str_radix(m.as_slice(), 8);
         if res.is_some() {
             unsafe { std::mem::transmute(res.unwrap()) }
         } else {
diff --git a/src/truncate/truncate.rs b/src/truncate/truncate.rs
index 286743ad7..e1002fb49 100644
--- a/src/truncate/truncate.rs
+++ b/src/truncate/truncate.rs
@@ -16,7 +16,6 @@ extern crate libc;
 
 use std::io::{File, Open, ReadWrite, fs};
 use std::io::fs::PathExtensions;
-use std::u64;
 
 #[path = "../common/util.rs"]
 mod util;
@@ -184,8 +183,8 @@ fn parse_size(size: &str) -> (u64, TruncateMode) {
             }
         }
         slice
-    }.to_string().into_bytes();
-    let mut number = match u64::parse_bytes(bytes.as_slice(), 10) {
+    }.to_string();
+    let mut number = match from_str::<u64>(bytes.as_slice()) {
         Some(num) => num,
         None => {
             crash!(1, "'{}' is not a valid number.", size)