pointer increment error

[WDT]

can someone tell me what's wrong with this line of code pls?

while(*buffer != "\0"){cout << static_cast<unsigned int>(*buffer); *buffer++;}

I keep getting the error:

28 C:\Dev-Cpp\MyProjs\fencrypt.cpp ISO C++ forbids comparison between pointer and integer

buffer is declared such:

char buffer[90];

thanks

[grumpy]

The complaint is caused by the while-condition (*buffer != "\0"). *buffer is a char (an integral type). "\0" is a string, which the compiler sees as an array of char and (when doing comparisons) arrays are sometimes threated like they're pointers.

Even though it is not resulting in a complaint from the compiler, the body of the loop is highly suspect as well: even more so if you apply the obvious fix (make the two things being compared of the same type) so the compiler does not complain about about the while-condition.

[CornedBee]

Make "\0" a character literal: '\0'.

Then, get a separate pointer for traversing, because you can't increment an array.

Once you've done that, you might as well use a for loop, which is more suitable for this kind of task.

for(const char *p = buffer; *p != '\0'; ++p) {
  std::cout << static_cast<unsigned int>(*p);
}

There's several more ways to accomplish this. But this is the simplest.

[WDT]

I got around it my own way thanks
I now have a new problem. I output the converted string into a file, close the file then re-open the file with ios::in.
Even though the string is stored as an interger cast I can't cast back to the ascii form:

while (!b_file.eof()) {
char i;
       i = static_cast<char>(b_file.get() );
       cout << i;
      
}

still only outputs numbers, not the original string.

[Elysia]

It's kinda silly to store all those chars as integers in the file (assuming you did, as you did cast the mess).
AFAIK, istream.get returns a reference to itself, so your code is invalid.
Further, using istream to read anything other than strings, might bite you later too. From my own experiments, of course.

[CornedBee]

You wrote the text serialization of the integer into the file, then you read individual bytes back and cast their numeric form to char - and you expect something even remotely similar to come out?

Oh, and about "while (!b_file.eof())", read the FAQ.

[WDT]

Oh, and about "while (!b_file.eof())", read the FAQ

can't find anything in the FAQ related to it. Also could you explain what text serialisation is pls??

[Elysia]

can't find anything in the FAQ related to it.

http://faq.cprogramming.com/cgi-bin/...&id=1043284351