Re: char *

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"Carmen Sei" <fatwallet951@xxxxxxxxx> wrote in message
news:r4gdv3lrrv3s93fr20mtnb5u6rsk0sj5n8@xxxxxxx
why the following compile is OK

but will crash when execute?

String literals (like "abcd") should not be modified. VC compiler
actually stores them in a block of memory marked read-only, so any
attempt to modify them generates a hardware exception (what you call a
crash).

For backward compatibility with C, a string literal (whose type,
formally, is an array of const char) can be implicitly converted to
char*, which gives a false impression that it can in fact be written to.
It can't. Don't do that.

String literals should not be confused with a special form of
initializer that can be used for char arrays:

char* p = "abcd"; // string literal
char arr[] = "abcd"; // initializer

The latter is simply a more compact form of this equivalent statement:

char arr[] = {'a', 'b', 'c', 'd', '\0'};

Character arrays can of course be modified (whether initialized with
what looks like a string literal but isn't, or otherwise).
--
With best wishes,
Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925


.

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