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copied!<p>You <a href="http://c-faq.com/aryptr/arraylval.html" rel="noreferrer">can't assign anything to an array variable in C</a>. It's not a 'modifiable lvalue'. From the spec, <strong>§6.3.2.1 Lvalues, arrays, and function designators</strong>:</p> <blockquote> <p>An <em>lvalue</em> is an expression with an object type or an incomplete type other than <strong><code>void</code></strong>; if an lvalue does not designate an object when it is evaluated, the behavior is undefined. When an object is said to have a particular type, the type is specified by the lvalue used to designate the object. A <em>modifiable lvalue</em> is an lvalue that does not have array type, does not have an incomplete type, does not have a const-qualified type, and if it is a structure or union, does not have any member (including, recursively, any member or element of all contained aggregates or unions) with a const-qualified type.</p> </blockquote> <p>The error message you're getting is a bit confusing because the array on the right hand side of the expression decays into a pointer before the assignment. What you have is semantically equivalent to:</p> <pre><code>message1 = &message2[0]; </code></pre> <p>Which gives the right side type <code>char *</code>, but since you still can't assign anything to <code>message1</code> (it's an array, type <code>char[100]</code>), you're getting the compiler error that you see. You can solve your problem by using <a href="http://linux.die.net/man/3/memcpy" rel="noreferrer"><code>memcpy(3)</code></a>:</p> <pre><code>memcpy(message1, message2, sizeof message2); </code></pre> <p>If you really have your heart set on using <code>=</code> for some reason, you could use use arrays inside structures... that's not really a recommended way to go, though.</p>

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