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    <p>In C, "strings" are just plain <code>char</code> arrays. Therefore, you can't directly concatenate them with other "strings". </p> <p>You can use the <code>strcat</code> function, which appends the string pointed to by <code>src</code> to the end of the string pointed to by <code>dest</code>:</p> <pre><code>char *strcat(char *dest, const char *src); </code></pre> <p>Here is an <a href="http://www.cplusplus.com/reference/clibrary/cstring/strcat.html" rel="noreferrer">example from cplusplus.com</a>:</p> <pre><code>char str[80]; strcpy(str, "these "); strcat(str, "strings "); strcat(str, "are "); strcat(str, "concatenated."); </code></pre> <p>For the first parameter, you need to provide the destination buffer itself. The destination buffer must be a char array buffer. E.g.: <code>char buffer[1024];</code></p> <p><strong>Make sure</strong> that the first parameter has enough space to store what you're trying to copy into it. If available to you, it is safer to use functions like: <code>strcpy_s</code> and <code>strcat_s</code> where you explicitly have to specify the size of the destination buffer. </p> <p><em>Note</em>: A string literal cannot be used as a buffer, since it is a constant. Thus, you always have to allocate a char array for the buffer.</p> <p>The return value of <code>strcat</code> can simply be ignored, it merely returns the same pointer as was passed in as the first argument. It is there for convenience, and allows you to chain the calls into one line of code:</p> <pre><code>strcat(strcat(str, foo), bar); </code></pre> <p>So your problem could be solved as follows:</p> <pre><code>char *foo = "foo"; char *bar = "bar"; char str[80]; strcpy(str, "TEXT "); strcat(str, foo); strcat(str, bar); </code></pre>
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    1. POHow do I concatenate const/literal strings in C?
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    1. USBrian R. Bondy
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    1. POHow do I concatenate const/literal strings in C?
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    1. COWould you put "Be very careful that..." in bold, please? This can't be stressed enough. Misuse of strcat, strcpy, and sprintf are the heart of unstable/insecure software.
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      1. USplinth
    2. CO"static string" and "allocate your own buffer" may be misleading as the former could be interpreted to mean "static string buffer" and the latter to indicate dynamical allocation. +1 if you change to "You can never use a string literal as a buffer, you must always use your own buffer" or similar.
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      1. USRobert Gamble
    3. COWarning: As written, this code will leave a giant, gaping hole in your code for buffer overflow exploits.
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