Sleep

Sleep
You are encouraged to solve this task according to the task description, using any language you may know.

Write a program that does the following in this order:

• Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
• Print "Sleeping..."
• Sleep the main thread for the given amount of time.
• Print "Awake!"
• End.

Cf.

• Nautical bell

Ada

The Ada delay statement takes an argument of type Duration, which is a real number counting the number of seconds to delay. Thus, 2.0 will delay 2.0 seconds, while 0.001 will delay 0.001 seconds.

with Ada.Text_Io; use Ada.Text_Io;
with Ada.Float_Text_Io; use Ada.Float_Text_Io;
 
procedure Sleep is
   In_Val : Float;
begin
   Get(In_Val);
   Put_Line("Sleeping...");
   delay Duration(In_Val);
   Put_Line("Awake!");
end Sleep;

AutoHotkey

TrayTip, sleeping, sleeping
sleep, 2000 ; 2 seconds
TrayTip, awake, awake
Msgbox, awake

AutoIt

#AutoIt Version: 3.2.10.0
$sleep_me=InputBox("Sleep", "Number of seconds to sleep", "10", "", -1, -1, 0, 0)
Dim $sleep_millisec=$sleep_me*1000
MsgBox(0,"Sleep","Sleeping for "&$sleep_me&" sec")
sleep ($sleep_millisec)
MsgBox(0,"Awake","... Awaking")

AWK

 
# syntax: GAWK -f SLEEP.AWK [seconds]
BEGIN {
    print("Sleeping...")
    loop(ARGV[1])
    print("Awake!")
    exit(0)
}
function loop(seconds,  t) {
# awk lacks a sleep mechanism, so simulate one by looping
    t = systime()
    while (systime() < t + seconds) {}
}
 

commands and output:

GAWK "BEGIN{print(strftime())}"
GAWK -f SLEEP.AWK 3
GAWK "BEGIN{print(strftime())}"

Wed Jan 16 18:06:44 Eastern Standard Time 2013
Sleeping...
Awake!
Wed Jan 16 18:06:47 Eastern Standard Time 2013

BASIC

Works with: QuickBasic version 4.5

INPUT sec 'the SLEEP command takes seconds
PRINT "Sleeping..."
SLEEP sec
PRINT "Awake!"

"SLEEP" with no argument will sleep until a button is pressed on the keyboard (including modifier keys such as shift or control). Also, pressing a key while SLEEP is waiting for a specific amount of time (as above) will end the SLEEP.

ZX Spectrum Basic

Pressing a key will cut the pause short on the ZX Spectrum.

10 REM s is the number of seconds
20 LET s = 5
30 PRINT "Sleeping"
40 PAUSE s * 50
50 PRINT "Awake"

Batch File

The usual way to do this is to use the ping utility which waits a second between multiple tries. To wait n seconds one tells ping to make n + 1 tries and redirects the output:

Works with: Windows NT version 4

@echo off
set /p Seconds=Enter the number of seconds to sleep: 
set /a Seconds+=1
echo Sleeping ...
ping -n %Seconds% localhost >nul 2>&1
echo Awake!

A similar trick can be used to wait a certain number of milliseconds. The ping utility includes a /w option which specifies the timeout to wait for a reply. This coupled with an unreachable address (where the full timeout will be needed) leads to the following:

Works with: Windows 2000

@echo off
set /p MilliSeconds=Enter the number of milliseconds to sleep: 
echo Sleeping ...
ping -n 1 -w %MilliSeconds% 1.2.3.4 >nul 2>&1
echo Awake!

Starting with Windows Vista there is a command-line utility to wait a number of seconds:

Works with: Windows Vista

@echo off
set /p Seconds=Enter the number of seconds to sleep: 
echo Sleeping ...
timeout /t %Seconds% /nobreak >nul
echo Awake!

BBC BASIC

Works with: BBC BASIC for Windows

      INPUT "Enter the time to sleep in centiseconds: " sleep%
      PRINT "Sleeping..."
      WAIT sleep%
      PRINT "Awake!"

Whilst sleeping BBC BASIC for Windows periodically tests for the ESCape key being pressed.

C

Works with: POSIX

The function sleep needs seconds, which are read from the standard input.

#include <stdio.h>
#include <unistd.h>
 
int main()
{
  unsigned int seconds;
  scanf("%u", &seconds);
  printf("Sleeping...\n");
  sleep(seconds);
  printf("Awake!\n");
  return 0;
}

C++

Works with: C++11

#include <iostream>
#include <thread>
#include <chrono>
int main()
{
    unsigned long microseconds;
    std::cin >> microseconds;
    std::cout << "Sleeping..." << std::endl;
    std::this_thread::sleep_for(std::chrono::microseconds(microseconds));
    std::cout << "Awake!\n";
}
 

Works with: POSIX

#include <unistd.h>
#include <iostream>
 
using namespace std;
 
int main(int argc, char* argv[])
{
    useconds_t microseconds;
    cin >> microseconds;
    cout << "Sleeping..." << endl;
    usleep(microseconds);
    cout << "Awake!" << endl;
    return 0;
}

C#

using System;
using System.Threading;
 
class Program
{
    static void Main(string[] args)
    {
        int sleep = Convert.ToInt32(Console.ReadLine());
        Console.WriteLine("Sleeping...");
        Thread.Sleep(sleep); //milliseconds
        Console.WriteLine("Awake!");
    }
}

Clojure

(defn sleep [ms] ; time in milliseconds
  (println "Sleeping...")
  (Thread/sleep ms)
  (println "Awake!"))
; call it
(sleep 1000)

Common Lisp

(defun test-sleep ()
  (let ((seconds (read)))
    (format t "Sleeping...~%")
    (sleep seconds)
    (format t "Awake!~%")))
 
(test-sleep)

D

import std.stdio, core.thread;
 
void main() {
    write("Enter a time to sleep (in seconds): ");
 
    long secs;
    readf(" %d", &secs);
 
    writeln("Sleeping...");
    Thread.sleep(dur!"seconds"(secs));
    writeln("Awake!");
}

Output:

Enter a time to sleep (in seconds): 5
Sleeping...
Awake!

Delphi

program SleepOneSecond;
 
{$APPTYPE CONSOLE}
 
uses SysUtils;
 
var
  lTimeToSleep: Integer;
begin
  if ParamCount = 0 then
    lTimeToSleep := 1000
  else
    lTimeToSleep := StrToInt(ParamStr(1));
  WriteLn('Sleeping...');
  Sleep(lTimeToSleep); // milliseconds
  WriteLn('Awake!');
end.

E

You can't do that.

No, really. E's approach to timing, concurrency, and IO is non-blocking; if you want to wait for something, you say what you want to do when it happens — i.e. callbacks. There are no threads of control which can be stopped — except automatically when they just have nothing to do.

So, the closest thing possible to the task description is to wait for the specified time to pass, then do whatever the next thing is.

def sleep(milliseconds :int, nextThing) {
    stdout.println("Sleeping...")
    timer.whenPast(timer.now() + milliseconds, fn {
        stdout.println("Awake!")
        nextThing()
    })
}

EGL

program Sleep type BasicProgram{}
 
    // Syntax: 	sysLib.wait(time BIN(9,2) in)
 
    function main()
    	SysLib.writeStdout("Sleeping!");
        sysLib.wait(15); // waits for 15 seconds
        SysLib.writeStdout("Awake!");	
    end
 
end

Eiffel

The feature sleep is defined in the library class EXECUTION_ENVIRONMENT. So the demonstration class APPLICATION inherits from EXECUTION_ENVIRONMENT in order to make sleep available.

sleep takes an argument which declares the number of nanoseconds to suspend the thread's execution.

class
    APPLICATION
inherit
    EXECUTION_ENVIRONMENT
create
    make
feature -- Initialization
    make
            -- Sleep for a given number of nanoseconds.
        do
            print ("Enter a number of nanoseconds: ")
            io.read_integer_64
            print ("Sleeping...%N")
            sleep (io.last_integer_64)
            print ("Awake!%N")
        end
end

Output (sleeping 10 seconds):

Enter a number of nanoseconds: 10000000000
Sleeping...
Awake!

Erlang

Erlang doesn't really have such a thing as a main thread. However, sleeping any process can be done with the timer:sleep/1 function:

main() ->
    io:format("Sleeping...~n"),
    timer:sleep(1000), %% in milliseconds
    io:format("Awake!~n").

It is to be noted that Erlang's sleep function is implemented in Erlang with a timeout on a receive, so you may sometimes encounter the following way of sleeping a process:

main() ->
    io:format("Sleeping...~n"),
    receive
    after 1000 -> ok %% in milliseconds
    end,
    io:format("Awake!~n").

which is the way it is implemented in the timer module.

Factor

USING: calendar io math.parser threads ;
 
: read-sleep ( -- )
    readln string>number seconds
    "Sleeping..." print
    sleep
    "Awake!" print ;

Fantom

Fantom has a 'Duration' class, which uses time definitions with units: e.g., 5sec, 100ns, 5hr. These are used for input in the following program.

 
using concurrent
 
class Main
{
  public static Void main ()
  {
    echo ("Enter a time to sleep: ")
    input := Env.cur.in.readLine
    try
    {
      time := Duration.fromStr (input)
      echo ("sleeping ...")
      Actor.sleep (time)
      echo ("awake!")
    }
    catch
    {
      echo ("Invalid time entered")
    }
  }
}
 

Output:

Enter a time to sleep: 
5sec
sleeping ...
awake!

Forth

: sleep ( ms -- )
  ." Sleeping..."
  ms
  ." awake." cr ;

Fortran

program test_sleep
 
  implicit none
  integer :: iostat
  integer :: seconds
  character (32) :: argument
 
  if (iargc () == 1) then
    call getarg (1, argument)
    read (argument, *, iostat = iostat) seconds
    if (iostat == 0) then
      write (*, '(a)') 'Sleeping...'
      call sleep (seconds)
      write (*, '(a)') 'Awake!'
    end if
  end if
 
end program test_sleep

Frink

In Frink, all values have units of measure, and sleep functions take units of time, which can be seconds, nanoseconds, minutes, hours, etc. The user may enter values like "3 hours" or "1 ms". The units of measure are captured as first-class values in the language, and not hidden in comments nor implied in APIs.

 
do
  t = eval[input["Enter amount of time to sleep: ", "1 second"]]
while ! (t conforms time)
 
println["Sleeping..."]
sleep[t]
println["Awake!"]
 

Go

Technically, this varies from the task by sleeping the main goroutine rather than the main thread. The Go runtime multiplexes goroutines to operating system threads and the language does not provide direct access to threads.

package main
 
import "time"
import "fmt"
 
func main() {
    fmt.Print("Enter number of seconds to sleep: ")
    var sec float64
    fmt.Scanf("%f", &sec)
    fmt.Print("Sleeping…")
    time.Sleep(time.Duration(sec * float64(time.Second)))
    fmt.Println("\nAwake!")
}

Groovy

Solution:

def sleepTest = {
    println("Sleeping...")
    sleep(it)
    println("Awake!")
}

Test:

sleepTest(1000)
print '''
Hmmm. That was... less than satisfying.
How about this instead?
'''
Thread.start {
    (0..5).each {
        println it
        sleep(1000)
    }
}
sleepTest(5000)

Output:

Sleeping...
Awake!

Hmmm. That was... less than satisfying
How about this instead?
Sleeping...
0
1
2
3
4
Awake!
5

Haskell

import Control.Concurrent
 
main = do seconds <- readLn
          putStrLn "Sleeping..."
          threadDelay $ round $ seconds * 1000000
          putStrLn "Awake!"

HicEst

DLG(NameEdit = milliseconds, Button = "Go to sleep")
WRITE(StatusBar) "Sleeping ... "
SYSTEM(WAIT = milliseconds)
WRITE(Messagebox) "Awake!"

IDL

 
read,i,prompt='Input sleep time in seconds: '
print,'Sleeping...'
wait,i ; in seconds, but accepts floats(/fractional) as input
print,'Awake!'
 

Icon and Unicon

procedure main()
 
repeat {
   writes("Enter number of seconds to sleep :")
   s := reads()
   if s = ( 0 < integer(s)) then break
   }
 
write("\nSleeping for ",s," seconds.")
delay(1000 * s)
write("Awake!")
end

J

Solution:

sleep =: 6!:3
 
sleeping=: monad define
  smoutput 'Sleeping...'
  sleep y
  smoutput 'Awake!'
)

Example:

   sleeping 0.500          NB.  Sleep 500 milliseconds
Sleeping...
Awake!

Java

Works with: Java version 1.5+

 
import java.util.InputMismatchException;
import java.util.Scanner;
 
public class Sleep {
    public static void main(final String[] args) throws InterruptedException {
        try {
            int ms = new Scanner(System.in).nextInt(); //Java's sleep method accepts milliseconds
            System.out.println("Sleeping...");
            Thread.sleep(ms);
            System.out.println("Awake!");
        } catch (InputMismatchException inputMismatchException) {
            System.err.println("Exception: " + inputMismatchException);
        }
    }
}

JavaScript (in a web browser)

Generally, JavaScript in a web browser is event-loop based and (except for alert()) non-blocking. So, the closest thing possible to the task description is to do something once the specified time has passed.

<script>
 
  setTimeout(function () {
    document.write('Awake!')
  }, prompt("Number of milliseconds to sleep"));
 
  document.write('Sleeping... ');
 
</script>

Julia

 
print("Please enter sleep duration in seconds: ")
input = int(readline(STDIN))
println("Sleeping...")
sleep(input)
println("Awake!")
 

LabVIEW

Uses milliseconds. LabVIEW has no "main thread" so it must be forced with a sequence structure.
This image is a VI Snippet, an executable image of LabVIEW code. The LabVIEW version is shown on the top-right hand corner. You can download it, then drag-and-drop it onto the LabVIEW block diagram from a file browser, and it will appear as runnable, editable code.

Liberty BASIC

Input "Please input the number of milliseconds you would like to sleep. "; sleeptime
Print "Sleeping..."
CallDLL #kernel32, "Sleep", sleeptime As long, ret As void
Print "Awake!"
 

Logo

 
to sleep :n
print [Sleeping...]
wait :n                  ; units: 1/60th of a second
print [Awake.]
end
 

Mathematica

This function, as you can probably guess, takes its argument in seconds. While this function does tie up execution (but not with a busy wait), the Mathematica front end remains fully functional and can be used to stop the sleeping with Evaluation -> Abort Evaluation.

 
Sleep[seconds_] := (Print["Sleeping..."]; Pause[seconds]; Print["Awake!"];)
 

MATLAB / Octave

function sleep()
 
    time = input('How many seconds would you like me to sleep for? ');
    assert(time > .01);
    disp('Sleeping...');
    pause(time);
    disp('Awake!');
 
end

NetRexx

/* NetRexx */
options replace format comments java crossref symbols nobinary
 
runSample(arg)
return
 
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method sleep(secs) public static binary
  ms = (secs * 1000).format(null, 0) -- milliseconds, rounded to nearest integer
  say 'Sleeping...'
  do
    Thread.sleep(ms)
  catch ix = InterruptedException
    say 'Sleep interrupted!'
    ix.printStackTrace()
  end
  say 'Awake!'
  return
 
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method runSample(arg) public static
  secs = -1
  loop until \secs.datatype('N')
    if secs > 0 then do
      say 'Napping for' secs's'
      say
      sleep(secs)
    end
    say
    say 'How many seconds do you want me to sleep? (enter something non-numeric to terminate)\-'
    parse ask secs .
    say
    end
  say
  say 'Goodbye...'
  say
  return
 

NewLISP

(println "Sleeping..." )
(sleep 2000) ; Wait for 2 seconds
(println "Awake!")

Nimrod

import os, strutils
 
echo("Enter how long I should sleep (in milliseconds):")
var timed = parseInt(readLine(stdin).string)
echo("Sleeping...")
sleep(timed)
echo("Awake!")

Objective-C

Of course the same code of Sleep#C works for Objective-C. The following code uses a OpenStep derived framework (Cocoa, GNUstep...).

Works with: GNUstep

and

Works with: Cocoa

#import <Foundation/Foundation.h>
 
int main()
{
  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
  NSTimeInterval sleeptime;
 
  printf("wait time in seconds: ");
  scanf("%f", &sleeptime);
 
  NSLog(@"sleeping...");
  [NSThread sleepForTimeInterval: sleeptime];
  NSLog(@"awakening...");
 
  [pool release];
  return 0;
}

Objeck

 
bundle Default {
  class Test {
    function : Main(args : System.String[]) ~ Nil {
      if(args->Size() = 1) {
        "Sleeping..."->PrintLine();
        Thread->Sleep(args[0]->ToInt());
        "Awake!"->PrintLine();
      };
    }
  }
}
 

OCaml

#load "unix.cma";;
let seconds = read_int ();;
print_endline "Sleeping...";;
Unix.sleep seconds;; (* number is integer in seconds *)
print_endline "Awake!";;

or

#load "unix.cma";;
#directory "+threads";;
#load "threads.cma";;
let seconds = read_float ();;
print_endline "Sleeping...";;
Thread.delay seconds;; (* number is in seconds ... but accepts fractions *)
print_endline "Awake!";;

Oz

declare
  class TextFile from Open.file Open.text end
  StdIn = {New TextFile init(name:stdin)}
  WaitTime = {String.toInt {StdIn getS($)}}
in
  {System.showInfo "Sleeping..."}
  {Delay WaitTime} %% in milliseconds
  {System.showInfo "Awake!"}

PARI/GP

GP does not have threading built in and so cannot truly sleep; this is code for spin-idling.

gettime

The units are milliseconds.

sleep(ms)={
  print("Sleeping...");
  while((ms-=gettime()) > 0,);
  print("Awake!")
};
 
sleep(input())

alarm

Works with: PARI/GP version 2.4.3 and above on Linux

The units are seconds.

sleep(s)={
  print("Sleeping...");
  alarm(s);
  trap(alarmer,,while(1,));
  print("Awake!")
};
 
sleep(input())

Pascal

See Delphi

Perl

seconds:

$seconds = <>;
print "Sleeping...\n";
sleep $seconds; # number is in seconds
print "Awake!\n";

microseconds and nanoseconds using the Time::HiRes module:

use Time::HiRes qw( usleep nanosleep );
 
$microseconds = <>;
print "Sleeping...\n";
usleep $microseconds;
print "Awake!\n";
 
$nanoseconds = <>;
print "Sleeping...\n";
nanosleep $nanoseconds;
print "Awake!\n";

Perl 6

The sleep function argument is in units of seconds, but these may be fractional (to the limits of your system's clock).

my $sec = prompt("Sleep for how many microfortnights? ") * 1.2096;
say "Sleeping...";
sleep $sec;
say "Awake!";

Note that 1.2096 is a rational number in Perl 6, not floating point, so precision can be maintained even when dealing with very small powers of ten.

PHP

seconds:

$seconds = 42;
echo "Sleeping...\n";
sleep($seconds); # number is integer in seconds
echo "Awake!\n";

microseconds:

$microseconds = 42000000;
echo "Sleeping...\n";
usleep($microseconds); # number is integer in microseconds
echo "Awake!\n";

nanoseconds:

$nanoseconds = 42000000000;
echo "Sleeping...\n";
time_nanosleep($seconds, $nanoseconds); # first arg in seconds plus second arg in nanoseconds
echo "Awake!\n";

PicoLisp

(prinl "Sleeping..." )
(wait 2000)                # Wait for 2 seconds
(prinl "Awake!")

As wait will continue executing background events, another possibility (for a complete stop) is calling some external program like

(prinl "Sleeping..." )
(call 'sleep 2)            # Wait for 2 seconds
(prinl "Awake!")

PL/I

 
put ('sleeping');
delay (2000); /* wait for 2 seconds (=2000 milliseconds). */
put ('awake');
 

PowerShell

$d = [int] (Read-Host Duration in seconds)
Write-Host Sleeping ...
Start-Sleep $d
Write-Host Awake!

The -Milliseconds parameter to Start-Sleep can be used to allow for sub-second precision in sleeping.

Prolog

Works with SWI-Prolog.

rosetta_sleep(Time) :-
	writeln('Sleeping...'),
	sleep(Time),
	writeln('Awake!').
 

Protium

Literate mode

<@ SAYLIT>Number of seconds: </@><@ GETVAR>secs</@>
<@ SAYLIT>Sleeping</@>
<@ ACTPAUVAR>secs</@>
<@ SAYLIT>Awake</@>

French variable-length opcodes

<# MontrezLittéralement>Number of seconds: </#><# PrenezUneValeurVariable>secs</#>
<# MontrezLittéralement>Sleeping</#>
<# AgissezFaireUnePauseVariable>secs</#>
<# MontrezLittéralement>Awake</#>

(Simplified) Chinese fixed-length opcodes

<@ 显示_字串_>Number of seconds: </@><@ 获取_变量_>secs</@>
<@ 显示_字串_>Sleeping</@>
<@ 运行_暂停动变量_>secs</@>
<@ 显示_字串_>Awake</@>

PureBasic

Sleeping is performed with Delay() and a value in milliseconds. The time is accurate to approximately +/- 15 milliseconds.

If OpenConsole()  
 
  Print("Enter a time(milliseconds) to sleep: ")
  x.i = Val(Input())
  PrintN("Sleeping...")
  Delay(x) ;in milliseconds
  PrintN("Awake!")
  Print(#CRLF$ + #CRLF$ + "Press ENTER to exit")
  Input()
  CloseConsole()
EndIf

Python

import time
 
seconds = float(raw_input())
print "Sleeping..."
time.sleep(seconds) # number is in seconds ... but accepts fractions
print "Awake!"

R

The call to flush.console is only needed if buffering is turned on. See FAQ for R on windows. The time is given in seconds (fractions allowed, resolution is system dependent).

 
sleep <- function(time=1)
{
   message("Sleeping...")
   flush.console()      
   Sys.sleep(time)
   message("Awake!")
}
 
sleep()
 

Racket

 
#lang racket
(displayln "Enter a time (in seconds): ")
(define time (read))
(when (number? time)
  (displayln "Sleeping...")
  (sleep time)
  (displayln "Awake!"))
 

REBOL

rebol [
    Title: "Sleep Main Thread"
    Date: 2009-12-15
    Author: oofoe
    URL: http://rosettacode.org/wiki/Sleep_the_Main_Thread
]
 
naptime: to-integer ask "Please enter sleep time in seconds: "
print "Sleeping..."
wait naptime
print "Awake!"

Retro

Retro has no fine grained timer; so we have to make due with seconds.

: sleep ( n- )
  [ time [ time over - 1 > ] until drop ] times ;
  : test
    "\nTime to sleep (in seconds): " puts getToken toNumber
    "\nSleeping..." sleep
    "\nAwake!\n" ;

REXX

Not all REXX interpretors have the DELAY built-in function.

/*REXX program to sleep   x   seconds (base in the argument). */
parse arg secs .                       /*get a (possible) argument.     */
secs=word(secs 0,1)                    /*if not present, assume 0 (zero)*/
say 'Sleeping' secs "seconds."         /*tell 'em what's happening.     */
call delay(secs)                       /*snooze.  Hopefully, a short nap*/
say 'Awake!'                           /*and tell 'em we're running.    */

output after the following was used for input: </tt> 4.7 </tt>

Sleeping 4.7 seconds.
Awake!

Ruby

seconds = gets.to_f
puts "Sleeping..."
sleep(seconds) # number is in seconds ... but accepts fractions
# Minimum resolution is system dependent.
puts "Awake!"

Scala

import java.util.Scanner
 
object Sleeper extends Application {
		val input = new Scanner(System.in)
		val ms = input.nextInt
		System.out.println("Sleeping...")
		Thread.sleep(ms)
		System.out.println("Awake!")
}

Scheme

Many Scheme implementations support srfi-18, a multithreading library which provides a 'thread-sleep!' function. The following works in Chicken Scheme:

 
(use format)
(use srfi-18)
 
(format #t "Enter a time (in seconds): ")
(let ((time (read))) ; converts input to a number, if possible
  (if (number? time)
    (begin
      (format #t "Sleeping...~&")
      (thread-sleep! time)
      (format #t "Awake!~&"))
    (format #t "You must enter a number~&")))
 

Scheme implementations also provide alternative approaches. For example, Chicken Scheme has a 'posix' library which includes a 'sleep' function.

Seed7

The duration.s7i library defines the function wait, which takes an argument of type duration. Functions to create durations with years, months, days, hours, minutes, seconds and micro seconds exist also.

$ include "seed7_05.s7i";
  include "duration.s7i";
 
const proc: main is func
  local
    var integer: secondsToSleep is 0;
  begin
    write("Enter number of seconds to sleep: ");
    readln(secondsToSleep);
    writeln("Sleeping...");
    wait(secondsToSleep . SECONDS);
    writeln("Awake!");
  end func;

Smalltalk

Works with: Pharo

t := (FillInTheBlankMorph request: 'Enter time in seconds') asNumber.
Transcript show: 'Sleeping...'.
(Delay forSeconds: t) wait.
Transcript show: 'Awake!'.
 

Works with: Smalltalk/X

t := (Dialog request: 'Enter time in seconds') asNumber.
Transcript show: 'Sleeping...'.
(Delay forSeconds: t) wait.
Transcript show: 'Awake!'.
 

(of course, you can "Smalltalk at:#FillInTheBlankMorph put:Dialog", to be source compatible with Pharo)

Standard ML

(TextIO.print "input a number of seconds please: ";
let val seconds = valOf (Int.fromString (valOf (TextIO.inputLine TextIO.stdIn))) in
  TextIO.print "Sleeping...\n";
  OS.Process.sleep (Time.fromReal seconds);  (* it takes a Time.time data structure as arg,
                                               but in my implementation it seems to round down to the nearest second.
                                               I dunno why; it doesn't say anything about this in the documentation *)
  TextIO.print "Awake!\n"
end)

Suneido

function (time)
    {
    Print("Sleeping...")
    Sleep(time) // time is in milliseconds
    Print("Awake!")
    }

Tcl

Blocking example (the process is blocked preventing any background activity).

puts -nonewline "Enter a number of milliseconds to sleep: "
flush stdout
set millis [gets stdin]
puts Sleeping...
after $millis
puts Awake!

A non-blocking example where background activity will occur.

puts -nonewline "Enter a number of milliseconds to sleep: "
flush stdout
set millis [gets stdin]
set ::wakupflag 0
puts Sleeping...
after $millis set ::wakeupflag 1
vwait ::wakeupflag
puts Awake!

TI-89 BASIC

This example is in need of improvement: Do something less wasteful than a busy wait, if possible.

Local dur_secs,st0,st,seconds
Define seconds() = Func
  Local hms
  getTime()→hms
  Return ((hms[1] * 60 + hms[2]) * 60) + hms[3]
EndFunc
ClockOn
  
Prompt dur_secs
Disp "Sleeping..."
seconds()→st
st→st0
While when(st<st0, st+86400, st) - st0 < dur_secs
  seconds()→st
EndWhile
Disp "Awake!"

Toka

This makes use of the sleep() function from libc which suspends execution for a specified number of seconds.

1 import sleep as sleep()
[ ." Sleeping...\n" sleep() drop ." Awake!\n" bye ] is sleep

45 sleep

TUSCRIPT

 
$$ MODE TUSCRIPT
secondsrange=2
PRINT "Sleeping ",secondsrange," seconds "
WAIT #secondsrange
PRINT "Awake after Naping ",secondsrange, " seconds"
 

UNIX Shell

printf "Enter a time in seconds to sleep: "
read seconds
echo "Sleeping..."
sleep "$seconds"
echo "Awake!"

This uses the sleep(1) command. POSIX sleep(1) only takes an integer, as in sleep 2, so you can only sleep for a whole number of seconds. Some systems extend sleep(1) to take a decimal fraction, as in sleep 2.5.

VBScript

 
iSeconds=InputBox("Enter a time in seconds to sleep: ","Sleep Example for RosettaCode.org")    
WScript.Echo "Sleeping..."
WScript.Sleep iSeconds*1000		'Sleep is done in Milli-Seconds
WScript.Echo "Awake!"
 

Vedit macro language

#1 = Get_Num("Sleep time in 1/10 seconds: ")
Message("Sleeping...\n")
Sleep(#1)
Message("Awake!\n")