Re: skipping bytes

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From	John Gordon <gordon@panix.com>
Newsgroups	comp.lang.c
Subject	Re: skipping bytes
Date	Mon, 18 Jul 2011 21:35:30 +0000 (UTC)
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In <4e24a281$0$1929$bbae4d71@news.suddenlink.net> "Bill Cunningham" <nospam@nspam.invalid> writes:

>     I want to take a 700MB file and skip evey 200MB, so I thought of this.

You mean you want to copy the 700MB file to another file, omitting
200MB chunks?

> long * space=malloc(sizeof(long)*500000);

There's no need to allocate that much space for a simple copy operation.
You can copy, say, 8K or 16K at a time without allocating a huge buffer.

> That would be good for code wouldn't it? Now how to tell where I am in the 
> file. I have two choices. ftell() and fseek() or use f*pos() functions. 
> Would anyone have any suggestions?

The f*pos() functions handle files which are too large for ftell/fseek,
and they also have special code to handle multibyte stream content.

If you don't care about those two concerns, then either functions will
work.

(By the way, I got this information by doing a Google search on the
phrase "what is the difference between ftell and fgetpos?")

-- 
John Gordon                   A is for Amy, who fell down the stairs
gordon@panix.com              B is for Basil, assaulted by bears
                                -- Edward Gorey, "The Gashlycrumb Tinies"

Thread

skipping bytes "Bill Cunningham" <nospam@nspam.invalid> - 2011-07-19 05:15 -0400
  Re: skipping bytes John Gordon <gordon@panix.com> - 2011-07-18 21:35 +0000
    Re: skipping bytes "Bill Cunningham" <nospam@nspam.invalid> - 2011-07-19 05:43 -0400
      Re: skipping bytes blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-19 17:27 +0000
        Re: skipping bytes Chad <cdalten@gmail.com> - 2011-07-19 12:09 -0700
          Re: skipping bytes blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-19 21:34 +0000
        Re: skipping bytes "Bill Cunningham" <nospam@nspam.invalid> - 2011-07-20 03:17 -0400
          Re: skipping bytes blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-19 21:35 +0000
            Re: skipping bytes "Bill Cunningham" <nospam@nspam.invalid> - 2011-07-20 07:01 -0400
            Re: skipping bytes "Bill Cunningham" <nospam@nspam.invalid> - 2011-07-22 11:25 -0400
  Re: skipping bytes Ian Collins <ian-news@hotmail.com> - 2011-07-19 09:42 +1200

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