Xcode & passing command line arguments - c

Question

I just started working with C & Xcode and I've run into a little difficulty.
All I want to do is read a file from the command line and see the output in the terminal.
I think my problem lies with the path to the file that I want to read in. I'm using a Mac and the file is on my desktop, so the path should be Users/myName/Desktop/words.txt. Is this correct?
This is my code:
#import <Foundation/Foundation.h>
int main (int argc, const char* argv[]){
if(argc == 1){
NSLog(#" you must pass at least one arguement");
return 1;
}
NSLog(#"russ");
FILE* wordFile = fopen(argv[1] , "r");
char word[100];
while (fgets(word,100,wordFile)) {
NSLog(#" %s is %d chars long", word,strlen(word));
}
fclose(wordFile);
return 0;
}//main

Answer 1

If you need the path to a file in OS X, an easy way to get it is to just drag the file into the Terminal.app window where you are typing the command. Voila!

Answer 2

The path to the desktop is /Users/[username]/Desktop/
~/Desktop/ is a user-agnostic way of denoting this, ~ represents the current users home directory. It must be expanded using a method like stringByExpandingTildeInPath
Not sure about using C# (I've never used it on Mac OS X), but in Objective-C/Cocoa, you would do..
// Get array with first index being path to desktop
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDesktopDirectory, NSUserDomainMask, YES);
// Get the first element
NSString *desktopPath = [paths objectAtIndex:0];
// Append words.txt to path
NSString *theFilePath = [desktopPath stringByAppendingPathComponent:#"words.txt"];
NSLog(#"%#", theFilePath);
This is the most robust way of getting the Desktop path, as a user could technically move their Desktop folder else where (although this is pretty unlikely). Another valid option is to use the NSString method stringByExpandingTildeInPath:
NSString *desktop = [#"~/Desktop" stringByExpandingTildeInPath];
NSString *theFile = [desktop stringByAppendingPathComponent:#"words.txt"]
As I said, both those are in Objective-C, but it shouldn't be hard to translate to C#, assuming you can get at the Cocoa libraries.
The code you posted works correctly:
dbr:.../build/Debug $ ./yourcode ~/Desktop/words.txt
yourcode[2106:903] russ
yourcode[2106:903] this is words.txt is 17 chars long
Your terminal automatically expands the ~/ tilda path

Answer 3

Close... it's
/{Volume}/Users/myName/Desktop/words.txt
... where {Volume} is the name of your hard drive. You can also try using:
~/Desktop/words.txt
... where ~ is understood to mean "your home directory", but this might not resolve correctly.

Answer 4

(Note - this appears to be a C question, not a C# question)
Actually, you can do:
/Users/myName/Desktop/words.txt
You don't have to give the path to the volume.
However, to get the full path in C you'd do something like:
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
char *home, *fullPath;
home = getenv("HOME");
fullPath = strcat(home, "/Desktop/words.txt");
The issue you're running into with passing the filename as an argument is that you need to set the current working directory to the place where the file exists.