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copied!<pre><code>char *strPtr ="Hello" ; </code></pre> <p>Defines <code>strPtr</code> a pointer to char pointing to a string literal <code>"Hello"</code> -- the effective type of this pointer is <code>const char *</code>. No modification allowed through <code>strPtr</code> to the pointee (invokes UB if you try to do so). This is a backward compatibility feature for older C code. This convention is deprecated in C++0x. See Annex C:</p> <blockquote> <p><strong>Change: String literals made const</strong> The type of a string literal is changed from “array of char” to “array of const char.” [...] </p> <p><strong>Rationale:</strong> This avoids calling an inappropriate overloaded function, which might expect to be able to modify its argument. </p> <p><strong>Effect on original feature:</strong> Change to semantics of well-defined feature. Difficulty of converting: Simple syntactic transformation, because string literals can be converted to char*; (4.2). The most common cases are handled by a new but deprecated standard conversion:</p> <p><code>char* p = "abc"; // valid in C, deprecated in C++</code></p> <p><code>char* q = expr ? "abc" : "de"; // valid in C, invalid in C++</code></p> <p><strong>How widely used:</strong> Programs that have a legitimate reason to treat string literals as pointers to potentially modifiable memory are probably rare.</p> </blockquote> <pre><code>char strArray[] ="Hello"; </code></pre> <p>The declared type of <code>strPtr</code> is -- it is an array of characters of unspecified size containing the string <code>Hello</code> including the null terminator i.e. 6 characters. However, the initialization makes it a complete type and it's type is array of 6 characters. Modification via <code>strPtr</code> is okay.</p> <blockquote> <p>Where exactly do string literals are stored ?</p> </blockquote> <p>Implementation defined.</p>

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