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  1. PO
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    <p>You seem to have a faulty understanding of scanf's format string. %d explicitly means "I'm looking for an integer." This is why you only get the ASCII digit representation of the new line character.</p> <p>If you want to capture a new line as a character, your scanf needs to be %c. Then you can write a simple function that will convert the character representation of the integer into the actual integer. However %c will also only read a single character, so what you really want to use is %s to read a series of characters (also known as a String) that will be placed in a character pointer variable or character array if you know the maximum number of digits you're willing to accept. There are few differences between a character array and a String. Specifically a String is a character array that is null terminated (the last element of the string is the null character, \0).</p> <p>Long answer short, use a character pointer and change your scanf format string to be %s. Then check to see if the first character is \n. If it is not, convert the string to an integer and use that value to read your lines.</p> <p>Below is your code altered slightly to reflect this solution.</p> <pre><code>#include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; int main (int argc, char *argv[]) { FILE *file = fopen(argv[1], "r"); int newLineCounter, currentChar, numOfLines; printf("enter a number of lines of lines to be displayed\n"); scanf("%d", &amp;numOfLines); while ((currentChar = fgetc(file)) != EOF) { printf("%c", currentChar); //print character if (currentChar == '\n') //check for newLine character newLineCounter++; if (numOfLines == newLineCounter) { char* input; printf("\nenter a number of lines to be displayed or just return to quit\n"); scanf("%s", &amp;input); if( input[0] == '\n' || input[0] == '\0' ){ return 0; } else { numOfLines = atoi( input ); } newLineCounter = 0; //supposed to exit if return is pressed // if (numOfLines == '\n') //????why does this only execute when the decimal value of newline is entered // return 0; // } } //printf("%d lines in the text file\n", newLineCounter); fclose(file); return 0; } </code></pre>
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    1. POCapturing the return/enter as keystroke to quit program
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    1. USSnowInferno
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      1. VTDownMod
    1. CO%s isn't really that good. It will stop scanning on whitespace, so a line with multiple tokens will not be completely scanned, and the remaining tokens will be scanned later.
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      1. USronalchn
    2. COTrue, but from the context of the code given by the asker there is only one argument expected: a number or a new line. I think this is the ideal solution to the question given.
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      1. USSnowInferno
 

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