diff --git a/src/uu/basename/src/basename.rs b/src/uu/basename/src/basename.rs
index f7f4a3d08..9f3ce3cc4 100644
--- a/src/uu/basename/src/basename.rs
+++ b/src/uu/basename/src/basename.rs
@@ -7,11 +7,10 @@
 
 // spell-checker:ignore (ToDO) fullname
 
-#[macro_use]
-extern crate uucore;
-
 use clap::{crate_version, App, Arg};
 use std::path::{is_separator, PathBuf};
+use uucore::display::Quotable;
+use uucore::error::{UResult, UUsageError};
 use uucore::InvalidEncodingHandling;
 
 static SUMMARY: &str = "Print NAME with any leading directory components removed
@@ -32,7 +31,8 @@ pub mod options {
     pub static ZERO: &str = "zero";
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let args = args
         .collect_str(InvalidEncodingHandling::ConvertLossy)
         .accept_any();
@@ -44,12 +44,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
 
     // too few arguments
     if !matches.is_present(options::NAME) {
-        crash!(
-            1,
-            "{1}\nTry '{0} --help' for more information.",
-            uucore::execution_phrase(),
-            "missing operand"
-        );
+        return Err(UUsageError::new(1, "missing operand".to_string()));
     }
 
     let opt_suffix = matches.is_present(options::SUFFIX);
@@ -58,12 +53,18 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     let multiple_paths = opt_suffix || opt_multiple;
     // too many arguments
     if !multiple_paths && matches.occurrences_of(options::NAME) > 2 {
-        crash!(
+        return Err(UUsageError::new(
             1,
-            "extra operand '{1}'\nTry '{0} --help' for more information.",
-            uucore::execution_phrase(),
-            matches.values_of(options::NAME).unwrap().nth(2).unwrap()
-        );
+            format!(
+                "extra operand {}",
+                matches
+                    .values_of(options::NAME)
+                    .unwrap()
+                    .nth(2)
+                    .unwrap()
+                    .quote()
+            ),
+        ));
     }
 
     let suffix = if opt_suffix {
@@ -89,7 +90,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         print!("{}{}", basename(path, suffix), line_ending);
     }
 
-    0
+    Ok(())
 }
 
 pub fn uu_app() -> App<'static, 'static> {
diff --git a/src/uu/date/src/date.rs b/src/uu/date/src/date.rs
index adcf77024..bd814353f 100644
--- a/src/uu/date/src/date.rs
+++ b/src/uu/date/src/date.rs
@@ -18,6 +18,9 @@ use std::fs::File;
 use std::io::{BufRead, BufReader};
 use std::path::PathBuf;
 use uucore::display::Quotable;
+#[cfg(not(any(target_os = "macos", target_os = "redox")))]
+use uucore::error::FromIo;
+use uucore::error::{UResult, USimpleError};
 use uucore::show_error;
 #[cfg(windows)]
 use winapi::{
@@ -137,7 +140,8 @@ impl<'a> From<&'a str> for Rfc3339Format {
     }
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let syntax = format!(
         "{0} [OPTION]... [+FORMAT]...
  {0} [OPTION]... [MMDDhhmm[[CC]YY][.ss]]",
@@ -147,8 +151,10 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
 
     let format = if let Some(form) = matches.value_of(OPT_FORMAT) {
         if !form.starts_with('+') {
-            show_error!("invalid date {}", form.quote());
-            return 1;
+            return Err(USimpleError::new(
+                1,
+                format!("invalid date {}", form.quote()),
+            ));
         }
         let form = form[1..].to_string();
         Format::Custom(form)
@@ -176,8 +182,10 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     let set_to = match matches.value_of(OPT_SET).map(parse_date) {
         None => None,
         Some(Err((input, _err))) => {
-            show_error!("invalid date {}", input.quote());
-            return 1;
+            return Err(USimpleError::new(
+                1,
+                format!("invalid date {}", input.quote()),
+            ));
         }
         Some(Ok(date)) => Some(date),
     };
@@ -241,14 +249,12 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
                     let formatted = date.format(format_string).to_string().replace("%f", "%N");
                     println!("{}", formatted);
                 }
-                Err((input, _err)) => {
-                    show_error!("invalid date {}", input.quote());
-                }
+                Err((input, _err)) => show_error!("invalid date {}", input.quote()),
             }
         }
     }
 
-    0
+    Ok(())
 }
 
 pub fn uu_app() -> App<'static, 'static> {
@@ -348,20 +354,24 @@ fn parse_date<S: AsRef<str> + Clone>(
 }
 
 #[cfg(not(any(unix, windows)))]
-fn set_system_datetime(_date: DateTime<Utc>) -> i32 {
+fn set_system_datetime(_date: DateTime<Utc>) -> UResult<()> {
     unimplemented!("setting date not implemented (unsupported target)");
 }
 
 #[cfg(target_os = "macos")]
-fn set_system_datetime(_date: DateTime<Utc>) -> i32 {
-    show_error!("setting the date is not supported by macOS");
-    1
+fn set_system_datetime(_date: DateTime<Utc>) -> UResult<()> {
+    Err(USimpleError::new(
+        1,
+        "setting the date is not supported by macOS".to_string(),
+    ))
 }
 
 #[cfg(target_os = "redox")]
-fn set_system_datetime(_date: DateTime<Utc>) -> i32 {
-    show_error!("setting the date is not supported by Redox");
-    1
+fn set_system_datetime(_date: DateTime<Utc>) -> UResult<()> {
+    Err(USimpleError::new(
+        1,
+        "setting the date is not supported by Redox".to_string(),
+    ))
 }
 
 #[cfg(all(unix, not(target_os = "macos"), not(target_os = "redox")))]
@@ -370,7 +380,7 @@ fn set_system_datetime(_date: DateTime<Utc>) -> i32 {
 /// https://doc.rust-lang.org/libc/i686-unknown-linux-gnu/libc/fn.clock_settime.html
 /// https://linux.die.net/man/3/clock_settime
 /// https://www.gnu.org/software/libc/manual/html_node/Time-Types.html
-fn set_system_datetime(date: DateTime<Utc>) -> i32 {
+fn set_system_datetime(date: DateTime<Utc>) -> UResult<()> {
     let timespec = timespec {
         tv_sec: date.timestamp() as _,
         tv_nsec: date.timestamp_subsec_nanos() as _,
@@ -379,11 +389,9 @@ fn set_system_datetime(date: DateTime<Utc>) -> i32 {
     let result = unsafe { clock_settime(CLOCK_REALTIME, &timespec) };
 
     if result != 0 {
-        let error = std::io::Error::last_os_error();
-        show_error!("cannot set date: {}", error);
-        error.raw_os_error().unwrap()
+        Err(std::io::Error::last_os_error().map_err_context(|| "cannot set date".to_string()))
     } else {
-        0
+        Ok(())
     }
 }
 
@@ -392,7 +400,7 @@ fn set_system_datetime(date: DateTime<Utc>) -> i32 {
 /// See here for more:
 /// https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-setsystemtime
 /// https://docs.microsoft.com/en-us/windows/win32/api/minwinbase/ns-minwinbase-systemtime
-fn set_system_datetime(date: DateTime<Utc>) -> i32 {
+fn set_system_datetime(date: DateTime<Utc>) -> UResult<()> {
     let system_time = SYSTEMTIME {
         wYear: date.year() as WORD,
         wMonth: date.month() as WORD,
@@ -409,10 +417,8 @@ fn set_system_datetime(date: DateTime<Utc>) -> i32 {
     let result = unsafe { SetSystemTime(&system_time) };
 
     if result == 0 {
-        let error = std::io::Error::last_os_error();
-        show_error!("cannot set date: {}", error);
-        error.raw_os_error().unwrap()
+        Err(std::io::Error::last_os_error().map_err_context(|| "cannot set date".to_string()))
     } else {
-        0
+        Ok(())
     }
 }
diff --git a/src/uu/fold/src/fold.rs b/src/uu/fold/src/fold.rs
index c4cc16469..30a1012af 100644
--- a/src/uu/fold/src/fold.rs
+++ b/src/uu/fold/src/fold.rs
@@ -7,13 +7,12 @@
 
 // spell-checker:ignore (ToDOs) ncount routput
 
-#[macro_use]
-extern crate uucore;
-
 use clap::{crate_version, App, Arg};
 use std::fs::File;
 use std::io::{stdin, BufRead, BufReader, Read};
 use std::path::Path;
+use uucore::display::Quotable;
+use uucore::error::{FromIo, UResult, USimpleError};
 use uucore::InvalidEncodingHandling;
 
 const TAB_WIDTH: usize = 8;
@@ -30,7 +29,8 @@ mod options {
     pub const FILE: &str = "file";
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let args = args
         .collect_str(InvalidEncodingHandling::ConvertLossy)
         .accept_any();
@@ -46,10 +46,12 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     };
 
     let width = match poss_width {
-        Some(inp_width) => match inp_width.parse::<usize>() {
-            Ok(width) => width,
-            Err(e) => crash!(1, "illegal width value (\"{}\"): {}", inp_width, e),
-        },
+        Some(inp_width) => inp_width.parse::<usize>().map_err(|e| {
+            USimpleError::new(
+                1,
+                format!("illegal width value ({}): {}", inp_width.quote(), e),
+            )
+        })?,
         None => 80,
     };
 
@@ -58,9 +60,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         None => vec!["-".to_owned()],
     };
 
-    fold(files, bytes, spaces, width);
-
-    0
+    fold(files, bytes, spaces, width)
 }
 
 pub fn uu_app() -> App<'static, 'static> {
@@ -110,7 +110,7 @@ fn handle_obsolete(args: &[String]) -> (Vec<String>, Option<String>) {
     (args.to_vec(), None)
 }
 
-fn fold(filenames: Vec<String>, bytes: bool, spaces: bool, width: usize) {
+fn fold(filenames: Vec<String>, bytes: bool, spaces: bool, width: usize) -> UResult<()> {
     for filename in &filenames {
         let filename: &str = filename;
         let mut stdin_buf;
@@ -119,16 +119,17 @@ fn fold(filenames: Vec<String>, bytes: bool, spaces: bool, width: usize) {
             stdin_buf = stdin();
             &mut stdin_buf as &mut dyn Read
         } else {
-            file_buf = crash_if_err!(1, File::open(Path::new(filename)));
+            file_buf = File::open(Path::new(filename)).map_err_context(|| filename.to_string())?;
             &mut file_buf as &mut dyn Read
         });
 
         if bytes {
-            fold_file_bytewise(buffer, spaces, width);
+            fold_file_bytewise(buffer, spaces, width)?;
         } else {
-            fold_file(buffer, spaces, width);
+            fold_file(buffer, spaces, width)?;
         }
     }
+    Ok(())
 }
 
 /// Fold `file` to fit `width` (number of columns), counting all characters as
@@ -139,11 +140,15 @@ fn fold(filenames: Vec<String>, bytes: bool, spaces: bool, width: usize) {
 /// to all other characters in the stream.
 ///
 ///  If `spaces` is `true`, attempt to break lines at whitespace boundaries.
-fn fold_file_bytewise<T: Read>(mut file: BufReader<T>, spaces: bool, width: usize) {
+fn fold_file_bytewise<T: Read>(mut file: BufReader<T>, spaces: bool, width: usize) -> UResult<()> {
     let mut line = String::new();
 
     loop {
-        if let Ok(0) = file.read_line(&mut line) {
+        if file
+            .read_line(&mut line)
+            .map_err_context(|| "failed to read line".to_string())?
+            == 0
+        {
             break;
         }
 
@@ -190,6 +195,8 @@ fn fold_file_bytewise<T: Read>(mut file: BufReader<T>, spaces: bool, width: usiz
 
         line.truncate(0);
     }
+
+    Ok(())
 }
 
 /// Fold `file` to fit `width` (number of columns).
@@ -200,7 +207,7 @@ fn fold_file_bytewise<T: Read>(mut file: BufReader<T>, spaces: bool, width: usiz
 ///
 /// If `spaces` is `true`, attempt to break lines at whitespace boundaries.
 #[allow(unused_assignments)]
-fn fold_file<T: Read>(mut file: BufReader<T>, spaces: bool, width: usize) {
+fn fold_file<T: Read>(mut file: BufReader<T>, spaces: bool, width: usize) -> UResult<()> {
     let mut line = String::new();
     let mut output = String::new();
     let mut col_count = 0;
@@ -230,7 +237,11 @@ fn fold_file<T: Read>(mut file: BufReader<T>, spaces: bool, width: usize) {
     }
 
     loop {
-        if let Ok(0) = file.read_line(&mut line) {
+        if file
+            .read_line(&mut line)
+            .map_err_context(|| "failed to read line".to_string())?
+            == 0
+        {
             break;
         }
 
@@ -281,4 +292,6 @@ fn fold_file<T: Read>(mut file: BufReader<T>, spaces: bool, width: usize) {
 
         line.truncate(0);
     }
+
+    Ok(())
 }
diff --git a/src/uu/nl/src/nl.rs b/src/uu/nl/src/nl.rs
index 600ebace0..b004d2b74 100644
--- a/src/uu/nl/src/nl.rs
+++ b/src/uu/nl/src/nl.rs
@@ -8,14 +8,12 @@
 
 // spell-checker:ignore (ToDO) corasick memchr
 
-#[macro_use]
-extern crate uucore;
-
 use clap::{crate_version, App, Arg};
 use std::fs::File;
 use std::io::{stdin, BufRead, BufReader, Read};
 use std::iter::repeat;
 use std::path::Path;
+use uucore::error::{FromIo, UResult, USimpleError};
 use uucore::InvalidEncodingHandling;
 
 mod helper;
@@ -83,7 +81,8 @@ pub mod options {
     pub const NUMBER_WIDTH: &str = "number-width";
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let args = args
         .collect_str(InvalidEncodingHandling::ConvertLossy)
         .accept_any();
@@ -109,11 +108,10 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     // program if some options could not successfully be parsed.
     let parse_errors = helper::parse_options(&mut settings, &matches);
     if !parse_errors.is_empty() {
-        show_error!("Invalid arguments supplied.");
-        for message in &parse_errors {
-            println!("{}", message);
-        }
-        return 1;
+        return Err(USimpleError::new(
+            1,
+            format!("Invalid arguments supplied.\n{}", parse_errors.join("\n")),
+        ));
     }
 
     let mut read_stdin = false;
@@ -130,16 +128,16 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
             continue;
         }
         let path = Path::new(file);
-        let reader = File::open(path).unwrap();
+        let reader = File::open(path).map_err_context(|| file.to_string())?;
         let mut buffer = BufReader::new(reader);
-        nl(&mut buffer, &settings);
+        nl(&mut buffer, &settings)?;
     }
 
     if read_stdin {
         let mut buffer = BufReader::new(stdin());
-        nl(&mut buffer, &settings);
+        nl(&mut buffer, &settings)?;
     }
-    0
+    Ok(())
 }
 
 pub fn uu_app() -> App<'static, 'static> {
@@ -227,7 +225,7 @@ pub fn uu_app() -> App<'static, 'static> {
 }
 
 // nl implements the main functionality for an individual buffer.
-fn nl<T: Read>(reader: &mut BufReader<T>, settings: &Settings) {
+fn nl<T: Read>(reader: &mut BufReader<T>, settings: &Settings) -> UResult<()> {
     let regexp: regex::Regex = regex::Regex::new(r".?").unwrap();
     let mut line_no = settings.starting_line_number;
     // The current line number's width as a string. Using to_string is inefficient
@@ -248,7 +246,8 @@ fn nl<T: Read>(reader: &mut BufReader<T>, settings: &Settings) {
         _ => &regexp,
     };
     let mut line_filter: fn(&str, &regex::Regex) -> bool = pass_regex;
-    for mut l in reader.lines().map(|r| r.unwrap()) {
+    for l in reader.lines() {
+        let mut l = l.map_err_context(|| "could not read line".to_string())?;
         // Sanitize the string. We want to print the newline ourselves.
         if l.ends_with('\n') {
             l.pop();
@@ -372,6 +371,7 @@ fn nl<T: Read>(reader: &mut BufReader<T>, settings: &Settings) {
             line_no_width += 1;
         }
     }
+    Ok(())
 }
 
 fn pass_regex(line: &str, re: &regex::Regex) -> bool {
diff --git a/src/uu/nproc/src/nproc.rs b/src/uu/nproc/src/nproc.rs
index 16b8d8c3a..4ab1378b0 100644
--- a/src/uu/nproc/src/nproc.rs
+++ b/src/uu/nproc/src/nproc.rs
@@ -7,11 +7,10 @@
 
 // spell-checker:ignore (ToDO) NPROCESSORS nprocs numstr threadstr sysconf
 
-#[macro_use]
-extern crate uucore;
-
 use clap::{crate_version, App, Arg};
 use std::env;
+use uucore::display::Quotable;
+use uucore::error::{UResult, USimpleError};
 
 #[cfg(target_os = "linux")]
 pub const _SC_NPROCESSORS_CONF: libc::c_int = 83;
@@ -31,7 +30,8 @@ fn usage() -> String {
     format!("{0} [OPTIONS]...", uucore::execution_phrase())
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let usage = usage();
     let matches = uu_app().usage(&usage[..]).get_matches_from(args);
 
@@ -39,8 +39,10 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         Some(numstr) => match numstr.parse() {
             Ok(num) => num,
             Err(e) => {
-                show_error!("\"{}\" is not a valid number: {}", numstr, e);
-                return 1;
+                return Err(USimpleError::new(
+                    1,
+                    format!("{} is not a valid number: {}", numstr.quote(), e),
+                ));
             }
         },
         None => 0,
@@ -66,7 +68,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         cores -= ignore;
     }
     println!("{}", cores);
-    0
+    Ok(())
 }
 
 pub fn uu_app() -> App<'static, 'static> {
diff --git a/src/uu/shuf/src/shuf.rs b/src/uu/shuf/src/shuf.rs
index 9a899d746..ce0af5ec2 100644
--- a/src/uu/shuf/src/shuf.rs
+++ b/src/uu/shuf/src/shuf.rs
@@ -7,14 +7,12 @@
 
 // spell-checker:ignore (ToDO) cmdline evec seps rvec fdata
 
-#[macro_use]
-extern crate uucore;
-
 use clap::{crate_version, App, Arg};
 use rand::Rng;
 use std::fs::File;
 use std::io::{stdin, stdout, BufReader, BufWriter, Read, Write};
 use uucore::display::Quotable;
+use uucore::error::{FromIo, UResult, USimpleError};
 use uucore::InvalidEncodingHandling;
 
 enum Mode {
@@ -52,7 +50,8 @@ mod options {
     pub static FILE: &str = "file";
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let args = args
         .collect_str(InvalidEncodingHandling::ConvertLossy)
         .accept_any();
@@ -65,7 +64,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         match parse_range(range) {
             Ok(m) => Mode::InputRange(m),
             Err(msg) => {
-                crash!(1, "{}", msg);
+                return Err(USimpleError::new(1, msg));
             }
         }
     } else {
@@ -77,8 +76,10 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
             Some(count) => match count.parse::<usize>() {
                 Ok(val) => val,
                 Err(_) => {
-                    show_error!("invalid line count: {}", count.quote());
-                    return 1;
+                    return Err(USimpleError::new(
+                        1,
+                        format!("invalid line count: {}", count.quote()),
+                    ));
                 }
             },
             None => std::usize::MAX,
@@ -97,22 +98,22 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         Mode::Echo(args) => {
             let mut evec = args.iter().map(String::as_bytes).collect::<Vec<_>>();
             find_seps(&mut evec, options.sep);
-            shuf_bytes(&mut evec, options);
+            shuf_bytes(&mut evec, options)?;
         }
         Mode::InputRange((b, e)) => {
             let rvec = (b..e).map(|x| format!("{}", x)).collect::<Vec<String>>();
             let mut rvec = rvec.iter().map(String::as_bytes).collect::<Vec<&[u8]>>();
-            shuf_bytes(&mut rvec, options);
+            shuf_bytes(&mut rvec, options)?;
         }
         Mode::Default(filename) => {
-            let fdata = read_input_file(&filename);
+            let fdata = read_input_file(&filename)?;
             let mut fdata = vec![&fdata[..]];
             find_seps(&mut fdata, options.sep);
-            shuf_bytes(&mut fdata, options);
+            shuf_bytes(&mut fdata, options)?;
         }
     }
 
-    0
+    Ok(())
 }
 
 pub fn uu_app() -> App<'static, 'static> {
@@ -180,22 +181,20 @@ pub fn uu_app() -> App<'static, 'static> {
         .arg(Arg::with_name(options::FILE).takes_value(true))
 }
 
-fn read_input_file(filename: &str) -> Vec<u8> {
+fn read_input_file(filename: &str) -> UResult<Vec<u8>> {
     let mut file = BufReader::new(if filename == "-" {
         Box::new(stdin()) as Box<dyn Read>
     } else {
-        match File::open(filename) {
-            Ok(f) => Box::new(f) as Box<dyn Read>,
-            Err(e) => crash!(1, "failed to open {}: {}", filename.quote(), e),
-        }
+        let file = File::open(filename)
+            .map_err_context(|| format!("failed to open {}", filename.quote()))?;
+        Box::new(file) as Box<dyn Read>
     });
 
     let mut data = Vec::new();
-    if let Err(e) = file.read_to_end(&mut data) {
-        crash!(1, "failed reading {}: {}", filename.quote(), e)
-    };
+    file.read_to_end(&mut data)
+        .map_err_context(|| format!("failed reading {}", filename.quote()))?;
 
-    data
+    Ok(data)
 }
 
 fn find_seps(data: &mut Vec<&[u8]>, sep: u8) {
@@ -231,22 +230,22 @@ fn find_seps(data: &mut Vec<&[u8]>, sep: u8) {
     }
 }
 
-fn shuf_bytes(input: &mut Vec<&[u8]>, opts: Options) {
+fn shuf_bytes(input: &mut Vec<&[u8]>, opts: Options) -> UResult<()> {
     let mut output = BufWriter::new(match opts.output {
         None => Box::new(stdout()) as Box<dyn Write>,
-        Some(s) => match File::create(&s[..]) {
-            Ok(f) => Box::new(f) as Box<dyn Write>,
-            Err(e) => crash!(1, "failed to open {} for writing: {}", s.quote(), e),
-        },
+        Some(s) => {
+            let file = File::create(&s[..])
+                .map_err_context(|| format!("failed to open {} for writing", s.quote()))?;
+            Box::new(file) as Box<dyn Write>
+        }
     });
 
     let mut rng = match opts.random_source {
-        Some(r) => WrappedRng::RngFile(rand::rngs::adapter::ReadRng::new(
-            match File::open(&r[..]) {
-                Ok(f) => f,
-                Err(e) => crash!(1, "failed to open random source {}: {}", r.quote(), e),
-            },
-        )),
+        Some(r) => {
+            let file = File::open(&r[..])
+                .map_err_context(|| format!("failed to open random source {}", r.quote()))?;
+            WrappedRng::RngFile(rand::rngs::adapter::ReadRng::new(file))
+        }
         None => WrappedRng::RngDefault(rand::thread_rng()),
     };
 
@@ -268,10 +267,10 @@ fn shuf_bytes(input: &mut Vec<&[u8]>, opts: Options) {
         // write the randomly chosen value and the separator
         output
             .write_all(input[r])
-            .unwrap_or_else(|e| crash!(1, "write failed: {}", e));
+            .map_err_context(|| "write failed".to_string())?;
         output
             .write_all(&[opts.sep])
-            .unwrap_or_else(|e| crash!(1, "write failed: {}", e));
+            .map_err_context(|| "write failed".to_string())?;
 
         // if we do not allow repeats, remove the chosen value from the input vector
         if !opts.repeat {
@@ -284,6 +283,7 @@ fn shuf_bytes(input: &mut Vec<&[u8]>, opts: Options) {
 
         count -= 1;
     }
+    Ok(())
 }
 
 fn parse_range(input_range: &str) -> Result<(usize, usize), String> {
diff --git a/src/uu/uname/src/uname.rs b/src/uu/uname/src/uname.rs
index 2c396081e..a4801dfc1 100644
--- a/src/uu/uname/src/uname.rs
+++ b/src/uu/uname/src/uname.rs
@@ -10,11 +10,9 @@
 
 // spell-checker:ignore (ToDO) nodename kernelname kernelrelease kernelversion sysname hwplatform mnrsv
 
-#[macro_use]
-extern crate uucore;
-
 use clap::{crate_version, App, Arg};
 use platform_info::*;
+use uucore::error::{FromIo, UResult};
 
 const ABOUT: &str = "Print certain system information.  With no OPTION, same as -s.";
 
@@ -49,11 +47,13 @@ const HOST_OS: &str = "Fuchsia";
 #[cfg(target_os = "redox")]
 const HOST_OS: &str = "Redox";
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let usage = format!("{} [OPTION]...", uucore::execution_phrase());
     let matches = uu_app().usage(&usage[..]).get_matches_from(args);
 
-    let uname = crash_if_err!(1, PlatformInfo::new());
+    let uname =
+        PlatformInfo::new().map_err_context(|| "failed to create PlatformInfo".to_string())?;
     let mut output = String::new();
 
     let all = matches.is_present(options::ALL);
@@ -115,7 +115,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     }
     println!("{}", output.trim_end());
 
-    0
+    Ok(())
 }
 
 pub fn uu_app() -> App<'static, 'static> {