C++ program not making file (bug)

Question

I'm trying to make 2 different programs - one that will write notes to a note file, and one that will read the notes. These two programs are called Notes and Noteread. Here is the source code for these programs.

// notes.cpp
include <iostream>                                                              
#include <fstream>                                                               
#include <ctime>                                                                 
using namespace std;                                                             

int main () {                                                                    
    time_t now = time(0);                                                        
    char* dt = ctime(&now);                                                      

    ofstream myfile;                                                             
    std::cout << ": ";                                                           
    string x{};                                                                  
    std::cin >> x;                                                               

    myfile.open ("~/notes.txt", ios_base::app);                                  
    myfile << "---- " << dt;                                                     
    myfile << x << '\n';                                                         
    myfile << "\n";                                                              
    myfile.close();                                                              
    return 0;                                                                    
}

// noteread.cpp
#include <bits/stdc++.h>                                                         

int main() {                                                                     
    system("less ~/notes.txt");                                                  
}

It's supposed to work like this.

jingle@variable [time] [~/notes] [master *]
-> % notes
: hello
jingle@variable [time] [~/notes] [master *]
-> % noteread
( less program)
--- time
hello
jingle@variable [time] [~/notes] [master *]
-> %

Although it ends up doing this:

jingle@variable [time] [~/notes] [master *]
-> % notes
: hello
jingle@variable [time] [~/notes] [master *]
-> % noteread
/home/jingle/notes.txt: No such file or directory
jingle@variable [time] [~/notes] [master *]
-> %

Another thing i did to debug this is make the notes.txt file and then run the program, but that turns out once running the program like i did above noteread finds the file but the file's blank. This is really weird and beyond my knowledge. Thanks in advance!

Include some error checking after each file operation. That will help you pinpoint the problem. — Paul Sanders, May 18 '20 at 21:55
**Recommended reading:** [Why should I not #include ?](https://stackoverflow.com/q/31816095/560648) — Asteroids With Wings, May 18 '20 at 21:58
Just don't use `~` in path, try out full path. (e.g. /home/user/notes/) — Jun Murakami, May 18 '20 at 22:05

score 0 · Answer 1 · answered May 18 '20 at 21:59

0

~/notes.txt isn't a "real" path. When you write it in your shell/terminal, it's expanded into /home/jingle/notes.txt. You wrote no code into your C++ program to do that.

I suggest you use a relative path instead, so just notes.txt. Document this fact, and invoke your program accordingly from the command-line with the proper current working directory for the task.

answered May 18 '20 at 21:59

Asteroids With Wings

17,071
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It DOES work this way, and in fact i used it before and it worked, but i want this to be universal. Meaning: 1 - I can run it from everywhere. (i can put it in /bin) 2 - It doesn't make a file where you are. I'd rather have that be an option. – electricalveins May 18 '20 at 22:16
@electricalveins Okay you know best then – Asteroids With Wings May 19 '20 at 13:19

score 0 · Answer 2 · answered May 19 '20 at 21:42

0

I used std::getenv to fix my problem. Then, i could get the HOME variable and use it in my program.

answered May 19 '20 at 21:42

electricalveins

3
3

C++ program not making file (bug)

2 Answers2