Opening a file in Mac OS X

Question

I am trying to open a text file with C++ in Mac OS X but I always get a Bus error.

I do not care where to put the file. I just need to read it. Am I writing its address wrong? or that Bus Error has another reason?

FILE *dic;
dic = fopen("DICT","rb");

dic = fopen("./DICT","rb");

dic = fopen("~/DICT","rb");

dic = fopen("~//DICT","rb");

Answer 1

With a little bit of clarification I see the problem in your C code (not C++!) is that fopen() returns NULL. You can check what the problem really is by reporting the detailed error:

if( (dic = fopen("DICT", "rb") == NULL ) {
    fprintf(stderr, "%s\n", perror("ERROR:"));
    exit(1);
}

If fopen() fails to find the file on the user's desktop and you wish your code to work on multiple platforms then you might define a function to get the user's desktop directory for using with fopen(). Something like

char* user_desktop(char* buf, size_t len)
{
    const char* const DESKTOP_DIR = 
#ifdef PC
    "C:\\Documents and Settings\\Pooya\\Desktop\\"
#elif defined(OSX)
    "/Users/Pooya/Desktop/"
#elif defined(LINUX)
    "/home/users/pooya/Desktop/"
// fail to compile if no OS specified ...
#endif
    return strncpy(buf, DESKTOP_DIR, len);
}

You probably want to look into a more robust way of getting the path of the desktop for each operating system. Most operating systems have an API for this, so do your research. There are also more robust ways of splitting behaviour for various platforms, you can look into that or open a different question about that. I just wanted to express my idea, of having a function which will return you the appropriate desktop path no matter on which platform you compile your code.

Answer 2

This code is correct! Pay attention to the directory where the executable is located. For sure the directory of the execution is not the same as you are expecting (I suppose, the directory of the .c files, right?).

I believe you are executing the app from the IDE. This is commom in Xcode, it mounts the exec`s in another location than that where the project files are located, and this such location that is considered when you execute the program, whether you execute it from the IDE or not!

Simply move the file you want to read to the location of the application and it will work properly.