C - Can't create a file on the current directory in OSX

Question

I have to save data in a file for a project (in C language). So i would like to use fopen to use fprintf to output my strings values on a file.

So, I do :

FILE * file;
file = fopen("./tmp.txt","w+");
outputData(); //my fonction to fprintf in the file
fclose(file);

But when i do that, this is not in the current directory but in my User directory of my compter (on OSX) and not on the current directory from where the app is lunch.

so, how can i change the current directory for my output file ? without hardCoding it ?

I'm executing my programme from: "/Users/Guillaume/OneDrive/Ephec/Os/Project1"

and the file tmp.txt is created in : "/Users/Guillaume" and i would like to create the file in the same directory as my project

Please show more information. Show how you run your program and show what the current directory of your terminal is when you run the program (use the shell command `pwd`). — Jabberwocky, Nov 07 '19 at 10:30
I don't understand what you want to do exactly. If you want to get location to your home dir, use `getenv("HOME")`. To get location to your current directory, use `getenv("PWD")` — Mihir Luthra, Nov 07 '19 at 10:34
sorry for the long time between my modifications i was at my lectures — Guillaume Lemer, Nov 07 '19 at 16:02
You seem to confuse the current directory (aka the working directory) and the directory where the executable resides. For the later, see [this question](https://stackoverflow.com/questions/1023306/finding-current-executables-path-without-proc-self-exe). — AProgrammer, Nov 07 '19 at 16:06

score 0 · Answer 1 · answered Nov 07 '19 at 10:30

0

You can try using full path, as on linux:

FILE * file;
file = fopen("/home/toto/tmp.txt","w+");

You can also check file access using access

answered Nov 07 '19 at 10:30

Hugo Martin

167
6

1

That's not what he's asking for, – Jabberwocky Nov 07 '19 at 10:31
Yes I know, but it works by using the full path. The output file is about the compiler. You can compile it by your own instead of using the default configuration – Hugo Martin Nov 07 '19 at 10:33
this doesn't answer my question, i asked if is it possible to do it without full path or i miss understand what you are saying. – Guillaume Lemer Nov 07 '19 at 12:36

score 0 · Accepted Answer · answered Dec 16 '19 at 16:44

I found a solution.

char path[PATH_SIZE/2];
strcpy(path,realpath(argv[0],0));

I use the argv[0] part of my programme to get the path in conjonction with realpath()

Man page : http://manpagesfr.free.fr/man/man3/realpath.3.html

and store it in a pre-define string path

C - Can't create a file on the current directory in OSX

2 Answers2