The C99 standard added a feature to dimension an array on-the-fly. The official term is variable length array or VLA. And while you might think everyone would love it, they don’t.
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The best way to declare a string literal in your code is to use array notation, like this:

char string[] = "I am some sort of interesting string.\n";
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Many programs rely upon external files to store data. When the file is missing, or not where it should be, the fopen() function returns a NULL pointer, which your code can act upon. Or, you can pre-check for the file’s existence by using the access() function.
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Have you ever had your C code run amok and had to press Ctrl+C to cancel?

Yeah, I’ve never had that happen to me either.
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A specific command to terminate a program was popular with programming languages long ago. For example, in BASIC you had the END command, which exited a program. For unusual circumstances, you could use the STOP command. It was the abnormal termination command, which stopped the program and also generated a “Break in line” message (in GW Basic). I’m sure other early languages also had commands to bail out of a program, and modern languages are the same.
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With the dawn of the new year, and my reflection upon the Clock program I blogged about recently, I’ve been thinking about time. Specifically, the time_t data type used with various C library time functions. Can this value contain negative time?
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My clock program is almost complete! It generates the current time as output and it updates the current time every minute. The only step remaining is to synchronize the program’s output with the system time. I want to ensure that when the system reads :00 seconds that the program ticks over to the next minute.
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From last week’s Lesson, the code I wrote for my clock program outputs the current hour and minute. I also want it to update, to keep running and output the next minute and so on. To me, that’s the difference between a clock program and code that just outputs the current time.
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The other day I had this strong urge to write myself a text mode clock program, one that runs at the command prompt. This desire harkens back to my days programming text mode computers: I don’t need a clock, I just wanted to see if I could code one.
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I’ve often wondered how it works. The printf() function has one argument minimum, a formatting string. Yet how does the compiler know how many other arguments are required? It’s not really a mystery, once you understand the concept of variable argument lists.
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