Lists the UTIs for a given list of file extensions

convert-ext-to-uti.m

#import <Foundation/Foundation.h>
#import <CoreServices/CoreServices.h>
#import <libgen.h>

/*
    convert-ext-to-uti

    Shows the Uniform Type Identifier(s) (UTI) for a
    file type based on its file extension. Output is
    a tab-separated tuple of (extension, UTI) per 
    line.

SYNOPSIS
    
    convert-ext-to-uti EXT [EXT...]
    
MORE INFO
    
    http://en.wikipedia.org/wiki/Uniform_Type_Identifier
    
EXAMPLE USAGE

    $ ./convert-ext-to-uti zip tgz
    zip	public.zip-archive
    tgz	org.gnu.gnu-zip-tar-archive
*/

int main(int argc, char *argv[]) {
    if (argc == 1) {
        printf("Usage: %s EXT [EXT...]\n", basename(argv[0]));
        return 1;
    }
    @autoreleasepool {
        for (int i = 1; i < argc; i++) {
            CFStringRef ext = CFStringCreateWithCString(kCFAllocatorDefault, argv[i], kCFStringEncodingUTF8);
            CFArrayRef types = UTTypeCreateAllIdentifiersForTag(kUTTagClassFilenameExtension, ext, nil);

            for (CFIndex idx = 0; idx < CFArrayGetCount(types); idx++) {
                CFStringRef type = CFArrayGetValueAtIndex(types, idx);
                
                printf("%s\t%s\n", [(__bridge NSString*)ext UTF8String], [(__bridge NSString*)type UTF8String]);
            }

            CFRelease(ext);
            CFRelease(types);
        }
    }
}