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Re: While loop with bool, same issue

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Just an FYI post...

Eric Sosman <esosman@comcast-dot-net.invalid> writes:

> On 10/14/2015 11:59 AM, Alla _ wrote:
>> Hello!
>>
>> I have decided to create a new topic, although
>> with the issue that I have already raised previously
>> (previous one is clear to me now).
>>
>> /** Counting words in a piece of text **/
>>
>> #include <stdio.h>
>> #include <stdbool.h>
>>
>> bool alphabetic (const char c)
>> {
>>      if ( (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') )
>>          return true;
>>      else
>>          return false;
>> }
>
>     Aside: The `if' is unnecessary.  You could simply do
>
> 	return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
>
> instead.  (I mention this mostly because you seem to use this
> silly pattern frequently.  It's not "wrong," just silly.)

Sadly, it's from the book.

>> void read_line (char buffer [])
>> {
>>      char character;
>>      int i = 0;
>>
>>      do
>>      {
>>          character = getchar();
>>          buffer[i] = character;
>>          i++;
>>      }
>>      while (character != '\n');
>>
>>      buffer[i - 1] = '\0'; // i - 1 because the index character was incremented one extra time inside the loop the last time it was executed
>> }
>
>     Aside: This is, more or less, a re-implementation of the
> COMPLETELY UNSAFE gets() function, a function SO BAD that it has
> been removed from the latest C Standard.  (I say "more or less"
> because there are errors: See question 12.1 on the comp.lang.c
> FAQ page at <http://www.c-faq.com/> for one of them, and you'll
> learn about the other if you ever type your system's end-of-input
> keystroke -- maybe CTRL-D or CTRL-Z -- at the keyboard.)

Again, it's from the textbook though with a slight name change and a
comment added.

Dorothy Parker comes to mind...  "This is not a book to be cast aside
lightly.  It should be thrown with great force."  (paraphrased)

No book on C should be cavalier about buffer overruns.

<snip>
-- 
Ben.

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While loop with bool, same issue Alla _ <modelling.data@gmail.com> - 2015-10-14 08:59 -0700
  Re: While loop with bool, same issue Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-10-14 13:31 -0400
    Re: While loop with bool, same issue August Karlstrom <fusionfile@gmail.com> - 2015-10-14 20:11 +0200
      Re: While loop with bool, same issue Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-10-14 14:26 -0400
    Re: While loop with bool, same issue Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-14 20:44 +0100
  Re: While loop with bool, same issue Siri Cruz <chine.bleu@yahoo.com> - 2015-10-14 10:45 -0700
    Re: While loop with bool, same issue Keith Thompson <kst-u@mib.org> - 2015-10-14 13:15 -0700
  Re: While loop with bool, same issue Keith Thompson <kst-u@mib.org> - 2015-10-14 11:42 -0700
    Re: While loop with bool, same issue Jorgen Grahn <grahn+nntp@snipabacken.se> - 2015-10-15 08:20 +0000

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