File size

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

In this task, the job is to verify the size of a file called "input.txt" for a file in the current working directory and another one in the file system root.

Ada

<ada>with Ada.Directories; use Ada.Directories; with Ada.Text_IO; use Ada.Text_IO;

procedure Test_File_Size is begin

  Put_Line (File_Size'Image (Size ("input.txt")) & " bytes");
  Put_Line (File_Size'Image (Size ("/input.txt")) & " bytes");

end Test_File_Size;</ada> Note that reference to the root directory, if there is any, is OS specific.

ALGOL 68

There is no build in way to find the size of an arbitrary file, especially of the file is a special channel, e.g. a tape device.

Conceptually the procedure "PROC set = (REF FILE file, INT page, line, character)VOID: ~ " could be used to do a binary search find the last page's page number. And if it is known that every page has the same number of lines, and every line has the same number of CHARS, and the character set is not compressible, then the size could be quickly calculated. Otherwise every page, and every line would have to be tallied.

It is probably much easier to use some an operating system library. This library is not part of the standard ALGOL 68 language definition.

C

POSIX: <c>#include <stdio.h>

1. include <sys/stat.h>

int main() {

 struct stat foo;
 stat("input.txt", &foo);
 printf("%ld\n", foo.st_size);
 stat("/input.txt", &foo);
 printf("%ld\n", foo.st_size);
 return 0;

}</c>

Clean

There is not function to get the file size, therefore we seek to the end and query the file pointer position.

import StdEnv

fileSize fileName world
    # (ok, file, world) = fopen fileName FReadData world
    | not ok = abort "Cannot open file"
    # (ok, file) = fseek file 0 FSeekEnd
    | not ok = abort "Cannot seek file"
    # (size, file) = fposition file
      (_, world) = fclose file world
    = (size, world)

Start world = fileSize "input.txt" world

D

Alternative ways to get file size in D. <d>module fileio ; import std.stdio ; import std.path ; import std.file ; import std.mmfile ; // NB: mmfile can treat the file as an array in memory import std.stream ;

string[] genName(string name){

 string cwd  = curdir ~ sep ; // on current directory
 string root = sep ;          // on root 
 // remove path, left only basename
 name = std.path.getBaseName(name) ;  
 // NB:in D ver.2, getBaseName is alias of basename
 return [cwd ~ name, root ~ name] ;

}

void testsize(string fname) {

 foreach(fn ; genName(fname)){
   try {
     writefln("file %s has size:", fn) ;
     writefln("%10d bytes by std.file.getSize (function),", std.file.getSize(fn)) ;
     writefln("%10d bytes by std.stream (class),", (new std.stream.File(fn)).size) ;
     writefln("%10d bytes by std.mmfile (class).", (new std.mmfile.MmFile(fn)).length) ;
   } catch (Exception e) {
     writefln(e.msg) ;
   }
 }

}

void main(){

 writefln("== test : File Size ==") ;
 testsize(r".\input.txt") ;

}</d>

Factor

"input.txt" file-info size>> .
    1321
"file-does-not-exist.txt" file-info size>>
 "Unix system call ``stat failed:"...

Forth

: .filesize ( addr len -- ) 2dup type ."  is "
  r/o open-file throw
  dup file-size throw  <# #s #> type ."  bytes long." cr
  close-file throw ;

 s" input.txt" .filesize
s" /input.txt" .filesize

Groovy

println new File('index.txt').length();
println new File('/index.txt').length();

Haskell

import System.IO

printFileSize filename = withFile filename ReadMode hFileSize >>= print

main = mapM_ printFileSize ["input.txt", "/input.txt"]

or

import System.Posix.File

printFileSize filename = do stat <- getFileStatus filename
                            print (fileSize stat)

main = mapM_ printFileSize ["input.txt", "/input.txt"]

Java

<java>import java.util.File; public class FileSizeTest {

  public static long getFileSize(String filename) {
      return new File(filename).length();
  }
  public static void test(String type, String filename) {
      System.out.println("The following " + type + " called " + filename + 
          " has a file size of " + getFileSize(filename) + " bytes."
      );
  }
  public static void main(String args[]) {
       test("file", "input.txt");
       test("file", File.seperator + "input.txt");
  }

}</java>

MAXScript

-- Returns filesize in bytes or 0 if the file is missing
getFileSize "index.txt"
getFileSize "\index.txt"

OCaml

<ocaml>let printFileSize filename =

 let ic = open_in filename in
 Printf.printf "%d\n" (in_channel_length ic);
 close_in ic ;;

printFileSize "input.txt" ;; printFileSize "input.txt" ;;</ocaml>

For files greater than Pervasives.max_int, one can use the module Unix.LargeFile: <ocaml>let printLargeFileSize filename =

 let ic = open_in filename in
 Printf.printf "%Ld\n" (LargeFile.in_channel_length ic);
 close_in ic ;;</ocaml>

Alternatively: <ocaml>#load "unix.cma" ;; open Unix ;; Printf.printf "%d\n" (stat "input.txt").st_size ;; Printf.printf "%d\n" (stat "/input.txt").st_size ;;</ocaml>

Perl

<perl>use File::Spec::Functions qw(catfile rootdir); print -s 'input.txt'; print -s catfile rootdir, 'input.txt';</perl>

Pop11

 ;;; prints file size in bytes
 sysfilesize('input.txt') =>
 sysfilesize('/input.txt') =>

Python

<python>import os

size = os.path.getsize('input.txt') size = os.path.getsize('/input.txt')</python>

RapidQ

File I/O is one of the things where RapidQ differs from standard Basic. RapidQ uses file streams.

Method 1: display file size using file streams

$INCLUDE "rapidq.inc"

DIM file AS QFileStream

FUNCTION fileSize(name$) AS Integer
    file.Open(name$, fmOpenRead)
    Result = file.Size
    file.Close
END FUNCTION

PRINT "Size of input.txt is "; fileSize("input.txt")
PRINT "Size of \input.txt is "; fileSize("\input.txt")

Method 2: using DIR$

FileName$ = DIR$("input.txt", 0)
PRINT "Size of input.txt is "; FileRec.Size
FileName$ = DIR$("\input.txt", 0)
PRINT "Size of \input.txt is "; FileRec.Size

Raven

'input.txt'  status.size
'/input.txt' status.size

Ruby

<python>size = File.size('input.txt') size = File.size('/input.txt')</python>

Toka

A trivial method follows:

 " input.txt"  "R" file.open dup file.size . file.close
 " /input.txt" "R" file.open dup file.size . file.close

A better method would be to define a new function that actually checks whether the file exists:

 [ "R" file.open
   dup 0 <> [ dup file.size . file.close ] ifTrue
   drop
 ] is display-size
 
 " input.txt"  display-size
 " /input.txt" display-size

UNIX Shell

du input.txt
du /input.txt

Visual Basic .NET

Platform: .NET

Works with: Visual Basic .NET version 9.0+

Dim local As New IO.FileInfo("input.txt")
Console.WriteLine(local.Length)

Dim root As New IO.FileInfo("\input.txt")
Console.WriteLine(root.Length)