CocoaDev

Is there a faster way to get the count of items in a directory than [[[NSFileManager defaultManager] directoryContentsAtPath:aPath] count]; ? Because I’m not interested in the items but only in the amount of items in that folder.

FSGetCatalogInfo should be much faster at obtaining this information, at least on HFS+ drives. —- OK, thanks. any hint which Info I need to query? kFSCatInfoFinderInfo? or kFSCatInfoValence - says it’s for folders only… or kFSCatinfoFinderXInfo? —- kFSCatInfoValence is what you want. -W —- Great, thanks. It also counts invisible files… any way to disable that? —- Nope. The question of whether a file is invisible or not is quite complex. You will have to walk the directory contents and determine each file’s visibility individually. —- Darn. well that defeats the whole purpose of the “avoiding nsfilemanager” thing. Is there something faster than directoryContentsAtPath?

FSGetCatalogInfoBulk. However, the cost needed to determine visibility of each file is likely to outweigh the cost of iterating the directory.

NSFileManager is used throughout the system and is basically just a wrapper for the appropriate POSIX and Carbon calls. Are you sure that NSFileManager is the cause of your bottleneck in this case? —- Apparently not. I just tested it, a count of nsfilemanager’s directorycontentsatpath is much faster than FSGetCatalogInfo (talking about milliseconds)… bottleneck sure is somewhere else.

The fastest way to count files on OS X is with fts_open(). This is a BSD function and it allocates memory sparingly. You can specify if you want each file’s stat or not with the flag FTS_NOSTAT. Just “man fts_open” for more info. –zootbobbalu

#include <sys/types.h> #include <sys/stat.h> #include #include <CoreFoundation/CoreFoundation.h> #include "fcntl.h" #include "unistd.h"

int main(int argc, char *argv[]) {

FTS *tree = NULL;
char *dirs[2] = {nil, nil};
FTSENT *entry = NULL;
unsigned dircount = 0, file_count = 0;
CFAbsoluteTime last = 0.0f, start = 0.0f;

if (argc < 2) {
	printf("fts_open <directory path>\n");
	goto bail;
}
 
dirs[0] = argv[1];

if (!(tree = fts_open(&dirs[0], FTS_PHYSICAL | FTS_NOSTAT, NULL))) {
	printf("unable to open directory at path: %s\n", argv[1]);
	goto bail;
}

start = CFAbsoluteTimeGetCurrent();
while (entry = fts_read(tree)) {

	switch (entry->fts_info) {
		case FTS_D:;
			dircount++;
			CFAbsoluteTime now = CFAbsoluteTimeGetCurrent();
			if (now - last > 0.2f) {
				printf("%05i|%6.1f sec|%s\n", dircount, now - start, entry->fts_path);
				last = now;
			}

			break;
		case FTS_F:;
			 file_count++;
			break;
		default: break;
	}
}
printf("dircount: %i file_count: %i time: %.1f sec\n", dircount, file_count, CFAbsoluteTimeGetCurrent() - start);

bail:;

if (tree) 
	fts_close(tree);

return 0; }