Check for resource fork in Objective C

Question

How do i check whether a file exists with resource fork or not?

Note : With out using the API's of CarbonCore->Resources.h, Since they are deprecated.

I will be able to open the file where there exist resource fork or not. But i need to check whether the resource fork exists or not. This is what exactly i'm looking for.

possible duplicate of [How to open and read resource forks in Obj-C](http://stackoverflow.com/questions/19400043/how-to-open-and-read-resource-forks-in-obj-c) — Darren, Aug 14 '15 at 06:51
@Darren, not a duplicate, testing whether the fork exists is not the same as actually reading the fork. — JWWalker, Aug 14 '15 at 16:24

score 4 · Accepted Answer · edited Apr 08 '19 at 11:52

4

Use getattrlist or fgetattrlist passing ATTR_FILE_RSRCLENGTH in the attrList parameter. see the man page for getattrlist.

edited Apr 08 '19 at 11:52

Thomas Tempelmann

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answered Aug 14 '15 at 16:14

geowar

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Thank you geowar, that answers my question – Abdul Naveed Aug 17 '15 at 08:23

score 1 · Answer 2 · answered Jun 14 '17 at 21:44

1

Alternatively

BOOL hasResourceFork = getxattr("/path/To/file", "com.apple.ResourceFork", NULL, 0, 0, 0) != -1;

That requires

#include <sys/xattr.h>

answered Jun 14 '17 at 21:44

vadian

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score 0 · Answer 3 · answered Apr 08 '19 at 11:51

For those who want to get the actual resource fork length, here's the code:

#include <sys/attr.h>

struct attrlist attrlist = {0};
attrlist.bitmapcount = ATTR_BIT_MAP_COUNT;
attrlist.fileattr    = ATTR_FILE_RSRCLENGTH;
typedef struct __attribute__((__packed__)) {
    uint32_t size;
    off_t forkSize;
} result_t;
result_t result = {0};
if (getattrlist (filepath, &attrlist, &result, sizeof(result), 0) == 0) {
    assert(sizeof(result)==result.size); // makes sure we got the struct right
    // now we find the rsrc fork size in result.forkSize
}

Check for resource fork in Objective C

3 Answers3