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    <p>You are correct, if the function would return a word, it'd be rather <code>char *getword()</code>. However, according to K&amp;R</p> <blockquote> <p>The function value is the first character of the word, or EOF for end of file, or the character itself if it is not alphabetic</p> </blockquote> <p>Returning an <code>int</code> is ok, as in C, a character is like an <code>int</code> having only 8 bits, in the [-128, +127] range.</p> <p>So where the word is returned?<br> In the <code>char *word</code> given as parameter. Initially <code>char *w</code> gets a copy of the <code>word</code> pointer, and then the characters read are set into the memory pointed to by <code>w</code>.</p> <p>Having <code>"in "</code> in the input buffer, <code>isspace</code> would return false, and <code>c</code> is assigned the non-space character. Then, <code>*w++</code> put that character at position [0] of word (<em>i</em>) increments the <code>w</code> pointer (<code>++</code>). <code>word[0]</code> contains 'i'.</p> <p>The <code>!isalpha</code> test is false, thus that part is skipped.</p> <p>Then characters are read from the input and stored into the next <code>w</code> position, until a non alphanumeric entry is read (or limit <code>lim</code> is reached) - in this non-alphanumeric case, the character read is actually put back into the input buffer, and <code>w</code> - which contains that undesired char - is not incremented (due to <code>break</code>). Then the following <code>*w = '\0'</code> overwrites that non-alpha char, and "close" the C string (in C strings ends with a character having a 0 value).</p> <p>In your example, that stores 'n' in <code>w</code>, increments <code>w</code>, then stores ' ' into <code>w</code> and performs the code for <code>!isalnum</code>, i.e. breaks the loop. Then since <code>w</code> was not incremented after storing ' ', the <code>*w = '\0'</code> replaces the space, and "closes" the string.</p> <p>[<em>the other half of the question has already been answered by someone else</em>]</p>
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    1. POreturning a word from getword using int; possible typo in binsearch
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    1. USRing Ø
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    1. POreturning a word from getword using int; possible typo in binsearch
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    1. CO`int` might be used to distinguish EOF from a valid char. The standard doesn't specify whether `char` is signed or unsigned so the -128,+127 bit is wrong.
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    2. COring0 and @J.F.Sebastian (since You commented here, I'll notify You as well). Thanks, but still I don't understand, even with Your explanation. You omitted how the main() can "know" that word[0], being let's say = 'i', has a missing part of "dea" - together "idea".
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      1. USPeter Cerba
    3. CO@PeterKowalski: `word` is a pointer. If you modify characters it points to in getword() then main() sees new values. getword() returns its result in the first parameter because C doesn't allow to return multiple values (one value to indicate EOF, another to store the result).
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