source: python/vendor/Python-2.6.5/Mac/BuildScript/seticon.m

/*
 * Simple tool for setting an icon on a file.
 */
#import <Cocoa/Cocoa.h>
#include <stdio.h>

int main(int argc, char** argv)
{
        if (argc != 3) {
                fprintf(stderr, "Usage: seticon ICON TARGET");
                return 1;
        }

        NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
        NSString* iconPath = [NSString stringWithUTF8String:argv[1]];
        NSString* filePath = [NSString stringWithUTF8String:argv[2]];

        [NSApplication sharedApplication];

        [[NSWorkspace sharedWorkspace]
                setIcon: [[NSImage alloc] initWithContentsOfFile: iconPath]
                forFile: filePath
                options: 0];
        [pool release];
        return 0;
}