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    <p>So the compiler output might look intimidating, but, as a beginner, the bit you care about is usually in English. This example is no exception:</p> <pre><code>Type and run 1.c: In function 'do_heading': Type and run 1.c:54: error: 'error_handler' undeclared (first use in this function) Type and run 1.c:54: error: (Each undeclared identifier is reported only once Type and run 1.c:54: error: for each function it appears in.) </code></pre> <p>It's telling you that <code>error_handler</code> is undeclared. It appears nowhere else in your program so there's no way you're able to use it here. Let's look at the line:</p> <pre><code>if ((stdout = fopen("PRT:","w")) == NULL) { printf ("Printer busy or disconnected\n"); error_handler; } </code></pre> <p>You should know that semicolons are one way to indicate the end of a statement and that good practice is to put just one statement on a line. Break it up:</p> <pre><code>if ((stdout = fopen("PRT:","w")) == NULL) { printf ("Printer busy or disconnected\n"); error_handler; } </code></pre> <p>Now it's obvious: you're just saying <code>error_handler;</code>; it's not doing anything, it's not a function call (no parentheses), not a variable you're assigning to or reading from so it's clearly a huge fat error. Delete it and try again.</p> <p>By the way, if the line appeared in the book exactly as you've put it here - with two semicolons on a line - then yes, you should throw it on the fire. Read Kernighan and Ritchie's "The C Programming Language" and do all the exercises in it - you will be amazed how quickly you go from knowing nothing to being ready to work on real programs.</p>
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    1. POError_handler… what?
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    1. USTim Kemp
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    1. COHi guys Got caugth up with other to-do's yesterday but I WILL CERTAINLY return to you! Merry Christmas to you all!
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      1. USKim Merrild
 

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