C code to watch a directory for changes

fswatcher.c

// gcc -o fswatcher -framework Carbon fswatcher.c

#include <CoreServices/CoreServices.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/dir.h>

static time_t timestamp = 0;

static void callback(ConstFSEventStreamRef stream,
                void *info,
                size_t n,
                void *paths,
                const FSEventStreamEventFlags flags[],
                const FSEventStreamEventId ids[])
{
    time_t next_timestamp = 0;
    int i;
    for (i=0; i<n; i++) {
        const char* dname = ((char**)paths)[i];
        uint dnamelen = strlen(dname);
        struct dirent *dp;
        DIR* d = opendir(dname);
        if (d == NULL)
            continue;
        while ((dp = readdir(d)) != NULL) {
            struct stat sb;

            if (*dp->d_name == '.')
                continue;

            char path[dp->d_namlen + dnamelen + 1]; // thank Pizza Hut for C99
            strcpy(path, dname);
            strcat(path, dp->d_name);

            if (lstat(path, &sb) < 0 && errno == EACCES)
                perror(NULL);
            else if (sb.st_mtime > timestamp) {
                printf("%s\n", path);
                if (sb.st_mtime > next_timestamp)
                    next_timestamp = sb.st_mtime;
            }
        }
        closedir(d);
    }
    timestamp = next_timestamp ? next_timestamp : time(NULL);
    fflush(stdout);
}

int main(int argc, char* argv[])
{
    timestamp = time(NULL);

    CFStringRef path = CFStringCreateWithCString(kCFAllocatorDefault, argv[1], kCFStringEncodingUTF8);
    CFArrayRef paths = CFArrayCreate(NULL, (const void **)&path, 1, NULL);
    FSEventStreamRef stream = FSEventStreamCreate(NULL,
            &callback,
            NULL,
            paths,
            kFSEventStreamEventIdSinceNow, /* TODO previous event ID */
            3.0,
            kFSEventStreamCreateFlagNone);
    FSEventStreamScheduleWithRunLoop(stream, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode);
    FSEventStreamStart(stream);
    CFRunLoopRun();
}