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    <p>This declaration:</p> <pre><code>char s[] = "hello"; </code></pre> <p>Creates <em>one</em> object - a <code>char</code> array of size 6, called <code>s</code>, initialised with the values <code>'h', 'e', 'l', 'l', 'o', '\0'</code>. Where this array is allocated in memory, and how long it lives for, depends on where the declaration appears. If the declaration is within a function, it will live until the end of the block that it is declared in, and almost certainly be allocated on the stack; if it's outside a function, it will <em>probably</em> be stored within an "initialised data segment" that is loaded from the executable file into writeable memory when the program is run.</p> <p>On the other hand, this declaration:</p> <pre><code>char *s ="hello"; </code></pre> <p>Creates <em>two</em> objects:</p> <ul> <li>a <strong>read-only</strong> array of 6 <code>char</code>s containing the values <code>'h', 'e', 'l', 'l', 'o', '\0'</code>, which has no name and has <em>static storage duration</em> (meaning that it lives for the entire life of the program); and</li> <li>a variable of type pointer-to-char, called <code>s</code>, which is initialised with the location of the first character in that unnamed, read-only array.</li> </ul> <p>The unnamed read-only array is typically located in the "text" segment of the program, which means it is loaded from disk into read-only memory, along with the code itself. The location of the <code>s</code> pointer variable in memory depends on where the declaration appears (just like in the first example).</p>
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    1. POWhat is the difference between char s[] and char *s?
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    1. COIn both declaration for "hello" memory is allocated at comiple time ?.And another thing char *p = "hello" here "hello" is stored in text segment as you stated in your answer...and what about char s[] = "hello" will it also store first in text segment part and during run time it will copy in stack as Rickard has stated in there answer. please clarify this point.
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      1. USNishant Kumar
    2. CO@Nishant: In the `char s[] = "hello"` case, the `"hello"` is just an initialiser telling the compiler how the array should be initialised. It may or may not result in a corresponding string in the text segment - for example, if `s` has static storage duration then it is likely that the only instance of `"hello"` will be in the initialised data segment - the object `s` itself. Even if `s` has automatic storage duration, it can be initialised by a sequence of literal stores rather than a copy (eg. `movl $1819043176, -6(%ebp); movw $111, -2(%ebp)`).
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    3. COThanks caf for your clarification.
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