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| From | "BartC" <bc@freeuk.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: how can i find the size of a binary file |
| Date | 2011-11-13 12:32 +0000 |
| Organization | A noiseless patient Spider |
| Message-ID | <j9odfc$umt$1@dont-email.me> (permalink) |
| References | <j9k4i8$tah$1@speranza.aioe.org> |
I generally use something like this:
long getfilesize(FILE* handle){
long p,size;
#if WINDOWS
p = ftell(handle); /* current position */
fseek(handle,0,SEEK_END); /* get EOF position */
size = ftell(handle); /* size in bytes */
fseek(handle,p,SEEK_SET); /* restore original position */
return size;
#else
puts("Sorry this system doesn't support quick file-size reporting");
exit(0);
return 0;
#endif
}
Notes:
o I've restricted this to work only for Windows, so WINDOWS must be set to 1
or 0 somewhere. You might try taking out this check to see what happens.
o The file must be open to determine the size
o If the system isn't Windows, or one where these calls will work, you can
try alternate code such as reading byte-by-byte; that will be slow but it
could work.
o The fseek() and such functions return an error code which I haven't
bothered to check (as I don't have error handling in this function)
o The functions I used are restricted to the range of 'long' (which I think
is 2GB in this case); I don't know what happens above 2GB, and don't have
files that big to test on. However being restricted to Windows, that could
have 64-bit versions available, as well as specialist functions which are
part of the OS rather than C.
o Making use of fstat() is also possible, but that is also frowned on here
so makes no difference.
o A file size of course could conceivably change by the time it is acted on.
But a file can also be deleted between calling fopen() and checking the
return value. So you can either give up programming right now, or just bear
these possibilities in mind.
o If I was interested in making this portable I might use a series of
#if/#elif checks for a range of platforms with appropriate code for each,
followed by an #else clause with some default code. But I'm not, and it
would probably turn out to be impossible anyway. So I don't worry about it.
--
Bartc
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how can i find the size of a binary file mark <nospam@nospam.com> - 2011-11-11 21:37 +0000
Re: how can i find the size of a binary file John Gordon <gordon@panix.com> - 2011-11-11 21:48 +0000
Re: how can i find the size of a binary file mark <nospam@nospam.com> - 2011-11-11 21:53 +0000
Re: how can i find the size of a binary file jacob navia <jacob@spamsink.net> - 2011-11-11 23:00 +0100
Re: how can i find the size of a binary file James Kuyper <jameskuyper@verizon.net> - 2011-11-11 17:20 -0500
Re: how can i find the size of a binary file Keith Thompson <kst-u@mib.org> - 2011-11-11 15:15 -0800
Re: how can i find the size of a binary file Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-11-12 12:43 +0200
Re: how can i find the size of a binary file Keith Thompson <kst-u@mib.org> - 2011-11-11 14:25 -0800
Re: how can i find the size of a binary file jacob navia <jacob@spamsink.net> - 2011-11-11 22:59 +0100
Re: how can i find the size of a binary file Barry Schwarz <schwarzb@dqel.com> - 2011-11-11 17:46 -0800
Re: how can i find the size of a binary file "io_x" <a@b.c.invalid> - 2011-11-14 18:18 +0100
Re: how can i find the size of a binary file Barry Schwarz <schwarzb@dqel.com> - 2011-11-14 20:55 -0800
Re: how can i find the size of a binary file Keith Thompson <kst-u@mib.org> - 2011-11-11 14:03 -0800
Re: how can i find the size of a binary file Barry Schwarz <schwarzb@dqel.com> - 2011-11-11 17:46 -0800
Re: how can i find the size of a binary file Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-11-14 01:21 -0800
Re: how can i find the size of a binary file Barry Schwarz <schwarzb@dqel.com> - 2011-11-14 20:55 -0800
Re: how can i find the size of a binary file Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-11-15 00:41 -0800
Re: how can i find the size of a binary file James Kuyper <jameskuyper@verizon.net> - 2011-11-15 06:53 -0500
Re: how can i find the size of a binary file Vincenzo Mercuri <vincenzo.mercuri@yahoo.it> - 2011-11-13 02:23 +0100
Re: how can i find the size of a binary file Nobody <nobody@nowhere.com> - 2011-11-13 02:47 +0000
Re: how can i find the size of a binary file jacob navia <jacob@spamsink.net> - 2011-11-13 08:44 +0100
Re: how can i find the size of a binary file Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-11-13 12:31 +0000
Re: how can i find the size of a binary file Roberto Waltman <usenet@rwaltman.com> - 2011-11-13 10:31 -0500
Re: how can i find the size of a binary file Nobody <nobody@nowhere.com> - 2011-11-19 07:37 +0000
Re: how can i find the size of a binary file Kaz Kylheku <kaz@kylheku.com> - 2011-11-19 17:54 +0000
Re: how can i find the size of a binary file Willem <willem@toad.stack.nl> - 2011-11-19 18:18 +0000
Re: how can i find the size of a binary file Keith Thompson <kst-u@mib.org> - 2011-11-19 14:19 -0800
Re: how can i find the size of a binary file Kaz Kylheku <kaz@kylheku.com> - 2011-11-20 01:14 +0000
Re: how can i find the size of a binary file Keith Thompson <kst-u@mib.org> - 2011-11-19 21:41 -0800
Re: how can i find the size of a binary file Kaz Kylheku <kaz@kylheku.com> - 2011-11-20 05:52 +0000
Re: how can i find the size of a binary file Keith Thompson <kst-u@mib.org> - 2011-11-19 22:23 -0800
Re: how can i find the size of a binary file David Thompson <dave.thompson2@verizon.net> - 2011-11-21 02:39 -0500
Re: how can i find the size of a binary file blp@cs.stanford.edu (Ben Pfaff) - 2011-11-11 14:32 -0800
Re: how can i find the size of a binary file Barry Schwarz <schwarzb@dqel.com> - 2011-11-11 17:46 -0800
Re: how can i find the size of a binary file Ike Naar <ike@sverige.freeshell.org> - 2011-11-11 22:41 +0000
Re: how can i find the size of a binary file "BartC" <bc@freeuk.com> - 2011-11-13 12:32 +0000
Re: how can i find the size of a binary file "BartC" <bc@freeuk.com> - 2011-11-13 14:56 +0000
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