ii 2023-07-21 07-53-48

  приведи пример на "C" : проверить если файл "test.txt" не существует, то создать его с содержимым "hello" 
 

Конечно, вот код на C:
C
#include 
#include 

int main() {
  FILE *file;

  // Check if file exists
  if (file = fopen("test.txt", "r")) {
    // File exists, do nothing
    fclose(file);
  } else {
    // File does not exist, create it
    file = fopen("test.txt", "w");
    fprintf(file, "hello");
    fclose(file);
  }

  return 0;
}

PHP


if (!file_exists("test.txt")) {
  $file = fopen("test.txt", "w");
  fwrite($file, "hello");
  fclose($file);
}




#!/bin/bash

if [ ! -f test.txt ]; then
  echo "hello" > test.txt
fi


#!/usr/bin/perl

if (! -e "test.txt") {
  open(my $fh, "> test.txt");
  print $fh "hello";
  close $fh;
}


Ruby
if !File.exist?("test.txt")
  File.open("test.txt", "w") do |f|
    f.puts "hello"
  end
end



Lisp
(if (not (probe-file "test.txt"))
  (with-open-file (stream "test.txt" :direction :output)
    (write-line "hello" stream))
  nil)



pascal
program test;
var
  file: text;

begin
  if not FileExists('test.txt') then
  begin
    AssignFile(file, 'test.txt');
    Rewrite(file);
    WriteLn(file, 'hello');
    CloseFile(file);
  end;
end.

C#
using System;

public class Program
{
    static void Main(string[] args)
    {
        if (!File.Exists("test.txt"))
        {
            System.IO.StreamWriter sw = new System.IO.StreamWriter("test.txt");
            sw.WriteLine("hello");
            sw.Close();
        }
    }
}


Forth:
: test
  if file-exists? "test.txt" do
    ." File already exists" cr
  else
    create "test.txt" file open
    "hello" file write
    file close
  end
;


Nim
import os

if not os.path.exists("test.txt"):
    open("test.txt", "w").write("hello")



ASM:

section .data
  file_name db "test.txt", 0

section .text
  global _start

_start:
  mov eax, 5 ; open file
  mov ebx, file_name
  mov ecx, 0 ; read/write
  mov edx, 0 ; no attributes
  int 0x80

  mov eax, 3 ; write to file
  mov ebx, eax ; file descriptor
  mov ecx, "hello"
  mov edx, 6 ; string length
  int 0x80

  mov eax, 6 ; close file
  mov ebx, eax ; file descriptor
  int 0x80

  mov eax, 1 ; exit
  mov ebx, 0 ; return code
  int 0x80
  


Java
import java.io.File;
import java.io.IOException;

public class Main {

    public static void main(String[] args) throws IOException {
        File file = new File("test.txt");
        if (!file.exists()) {
            file.createNewFile();
            FileWriter writer = new FileWriter(file);
            writer.write("hello");
            writer.close();
        }
    }
}


JavaScript
const fs = require("fs");

const file = "test.txt";

if (!fs.existsSync(file)) {
  fs.writeFileSync(file, "hello");
}


COBOL
IDENTIFICATION DIVISION.
PROGRAM-ID. TEST.

DATA DIVISION.
FILE SECTION.
FILE-CONTROL.
    SELECT FILE-1 ASSIGN TO "TEST.TXT".

WORKING-STORAGE SECTION.
   01 FILE-1-STATUS.
       05 F1-OPEN-STATUS PIC X.

PROCEDURE DIVISION.
MAIN-PROCEDURE.
    OPEN INPUT FILE-1.
    IF F1-OPEN-STATUS NOT = "00"
        THEN
            DISPLAY "File already exists".
        ELSE
            WRITE "hello" TO FILE-1.
    CLOSE FILE-1.

STOP RUN.


APL:
∇ f(file)
    if file.exists then do
        print("File already exists")
    end
    else do
        file.create
        file.write("hello")
    end
end

f("test.txt")
  


Fortran
program test

  implicit none

  character(len=8) :: file_name = "test.txt"

  open(1, file=file_name, status="new")
  if (status /= 0) then
    print *, "File already exists"
  else
    write(1, *) "hello"
  end if

  close(1)

end program test


Ada:
with Ada.Text_IO;

procedure Test is
  File : File_Type;
begin
  Open (File, "test.txt", Mode => Out_File);
  if File'Status /= 0 then
    Ada.Text_IO.Put_Line ("File already exists");
  else
    Ada.Text_IO.Put_Line ("hello");
  end if;
  Close (File);
end Test;