NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c++-part1/4562

Internet Message Format | 1996-08-06 | 1.7 KB

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From: Dirk Broer <[e-mail]>
Newsgroups: comp.lang.c++
Subject: Re: Interpreting whitespace w. cin
Date: Fri, 26 Jan 1996 20:00:09 -0800
Organization: NASA Goddard Space Flight Center -- Greenbelt, Maryland USA
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Blair Martin wrote:
>
> I want to write a program that uses new and delete to dynamically
> allocate exactly enough free memory to hold string input data.
>
> That is, instead of allocating a fixed array of
> characters from the stack, receive one character at a time and
> continually allocate, copy, and release space so that the physical
> and logical lengths of the buffer area are always the same.
> When the newline character is encountered, print the string
> and release the space. Then prompt for the next string. When
> EOF is entered, terminate the program.
>
> The problem is with a loop like
>
>     while (!(cin >> input).eof())
>     {
>             ...
>     }
>
> there is no way to know when a newline is encountered since
> all whitespace is ignored.
>
> Is there another way to do this?
>
> blair

Try this - not pretty as far as memory usage goes but it might work for
you:

char    buffer[256];

while( !(cin.getline( buffer, 256 ).eof()) )
{
    strstream    temp;

    temp << buffer;
    while (!(temp >> input).eof())
    {
             ...
    }
}

Ok, not pretty - but it basically parses cin line by line and then parses
the individual lines into tokens.

Dirk