Re: File size questions
Re: File size questions
- Subject: Re: File size questions
- From: Peter <email@hidden>
- Date: Fri, 16 Aug 2002 09:45:38 +0800
Thanks for your answer.
BTW sometimes I use stat() (man stat) to check file size similar to
NSFileManager. I do a sizeof(off_t) and it is confirmed to 8 bytes in
size (long long).
Funny off_t is typedef as signed long long,
snippet from <sys/types.h>
typedef u_int64_t u_quad_t; /* quads */
typedef int64_t quad_t;
typedef quad_t off_t; /* file offset */
Now I realized even lseek() is using 64 bit pointers.
Thanks again.
Peter.
On Friday, August 16, 2002, at 06:29 AM, Kirk Kerekes wrote:
On Thursday, August 15, 2002, at 11:13 AM, cocoa-dev-
email@hidden wrote:
Message: 11
Date: Thu, 15 Aug 2002 22:28:44 +0800
Subject: Help : File size questions
From: Peter <email@hidden>
To: email@hidden
Hello,
Recently stumble a very big file (about 3.3 GB), however I keep getting
incorrect file size. I supposed I have hit 32 bit signed int limit. By
looking the snippet below, how do I over come this problem.
fattrs = [fileMgr fileAttributesAtPath:pathStr traverseLink:YES];
filesize = [[fattrs objectForKey:NSFileSize] intValue];
A few questions,
1) On the doc. NSFileSize returns NSNumber, what is biggest number will
it hold ?
The largest _integer_ is a long long, which is 8 bytes. This can be
inferred by looking at the NSNumber documentation, at the:
- (long long)longLongValue;
and
- (unsigned long long)unsignedLongLongValue;
-- methods. It may be a leap of faith to assume that the NSNumber
returned for the NSFileSize attribute actually contains a long long,
but it isn't a very big leap.
2) What is the biggest file size for HFS+ and UFS ?
The same as an unsigned-long-long NSNumber: 64 bits or "over 9 exabytes
(2^
63 - 1)"
3) What about stat() function, does it return file size value greater
than 4 billion ( bigger than unsigned long) ?
Presumably. Don't know. Doesn't seem relevant.
_______________________________________________
cocoa-dev mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/cocoa-dev
Do not post admin requests to the list. They will be ignored.