Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.c > #13035

Re: No fread and fwrite for wide characters?

Show all headers | View raw

On 11/10/2011 12:26 PM, Lauri Alanko wrote:
> It seems that the standard I/O operations for wide characters are
> conspicuously lacking functions that read or write an array of
> arbitrary wide characters into a stream. E.g. for writing, there's
> only fputws, which writes a L'\0'-terminated string, not including the
> terminator. So if there's a buffer that may contain L'\0', one has to
> iterate it using fputwc, maybe with the assistance of fputws if an
> exact count of successfully written characters is not needed.
> 
> The workaround is not a big deal, but this seems like a strange
> omission, since otherwise there are wide I/O counterparts for all
> basic byte I/O operations. Granted, mixing text and null characters is
> not very common, but it does happen, e.g. when null characters are
> used as field separators.
> 
> So does anyone have an idea why "fwwrite" and "fwread" are missing?

I'm not sure exactly what behavior you want fwwrite() to have. Here's
how the standard describes fwrite():

> 7.19.8.2 The fwrite function
> Synopsis
>       #include <stdio.h>
>       size_t fwrite(const void * restrict ptr,
>            size_t size, size_t nmemb,
>            FILE * restrict stream);
>
> Description
> The fwrite function writes, from the array pointed to by ptr, up to
nmemb elements
> whose size is specified by size, to the stream pointed to by stream. For each object,
> size calls are made to the fputc function, taking the values (in order) from an array of
> unsigned char exactly overlaying the object. The file position indicator for the
> stream (if defined) is advanced by the number of characters successfully written. If an
> error occurs, the resulting value of the file position indicator for the stream is
> indeterminate.
>
> Returns
> The fwrite function returns the number of elements successfully written, which will be
> less than nmemb only if a write error is encountered. If size or nmemb is zero,
> fwrite returns zero and the state of the stream remains unchanged.

Could you modify that description so that it describes what you want for
fwwrite()?

Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

No fread and fwrite for wide characters? Lauri Alanko <la@iki.fi> - 2011-11-10 17:26 +0000
  Re: No fread and fwrite for wide characters? James Kuyper <jameskuyper@verizon.net> - 2011-11-10 12:34 -0500
    Re: No fread and fwrite for wide characters? Lauri Alanko <la@iki.fi> - 2011-11-10 17:58 +0000
      Re: No fread and fwrite for wide characters? James Kuyper <jameskuyper@verizon.net> - 2011-11-10 13:38 -0500
        Re: No fread and fwrite for wide characters? Lauri Alanko <la@iki.fi> - 2011-11-10 23:23 +0000
          Re: No fread and fwrite for wide characters? Harald van Dijk <truedfx@gmail.com> - 2011-11-11 09:33 -0800
            Re: No fread and fwrite for wide characters? Lauri Alanko <la@iki.fi> - 2011-11-12 00:09 +0000
          Re: No fread and fwrite for wide characters? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-11-12 00:28 +0200
            Re: No fread and fwrite for wide characters? Ike Naar <ike@sverige.freeshell.org> - 2011-11-11 22:58 +0000
              Re: No fread and fwrite for wide characters? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-11-12 14:07 +0200
            Re: No fread and fwrite for wide characters? James Kuyper <jameskuyper@verizon.net> - 2011-11-11 18:00 -0500

csiph-web