A basic C language process is passing a value to a function. If you’re an old hand, you might say, “Yeah, well, so?” For a beginning programmer, however, functions and their arguments can be a confusing and intimidating ordeal.
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\nA function in C can:<\/p>\n
A function that neither accepts nor returns a value is a void<\/em> function. I call it a function that doesn’t funct<\/em>. That label doesn’t imply that the function is unnecessary or that your programming skills are weak when you create a void<\/em> function. In fact, it doesn’t mean anything. I frequently use void<\/em> functions to store repetitious code in my programs. Here’s an example of such a function:<\/p>\n The pany()<\/em> function displays a prompt and waits for the Enter key to be pressed. It requires no arguments and returns no values, which is why the word void<\/em> is used in its declaration.<\/p>\n Values passed to a function are referred to as arguments<\/em>. Functions can accept any quantity of arguments, from zero (void<\/em>) to whatever is practical. The quantity depends on what the function does. All arguments must be declared as a specific variable type. The arguments are also given names for reference within the function. For example:<\/p>\n The guess()<\/em> function has a single argument, an int<\/em> value. The variable The value 3 is “passed” to the guess()<\/em> function. Then, within that function, the value is referenced by variable What can be confusing, especially for a beginner, is that the function could also be called by using a variable. For example:<\/p>\n Above, the int<\/em> variable Remember from my C programming books, variables are local<\/em> to their functions. Unless A function in the C language returns only one value. That value is specified as the function’s variable type. For example:<\/p>\n Above, the whatever()<\/em> function returns an int<\/em> value. The function has no arguments.<\/p>\n Above, the middle()<\/em> function returns a char<\/em> value. The function accepts a single string as an argument, a char<\/em> pointer.<\/p>\n Functions in C cannot return more than a single value. When you absolutely need such a function (and I can’t think of any examples off the top of my head) you must use global variables.<\/p>\n What about functions that return a structure variable? When that happens, the structure must be defined as a global variable, otherwise it can’t be used outside of the function. Beyond that, functions in the C language return only a single value, or no value at all.<\/p>\n","protected":false},"excerpt":{"rendered":" Here’s a basic review, or some pointers if you’re just starting, on how a function’s arguments work. Continue reading \r\nvoid pany(void)\r\n{\r\n printf(\"Press Enter to continue:\");\r\n getchar();\r\n}<\/pre>\nvoid guess(int tries)<\/code><\/p>\ntries<\/code> is used within the function to represent the int<\/em> value passed to the function. For example, elsewhere in the code you may see:<\/p>\nguess(3);<\/code><\/p>\ntries<\/code>.<\/p>\nguess(attempt);<\/code><\/p>\nattempt<\/code> is used to call the guess()<\/em> function. The value of attempt<\/code> is passed to the function — the value only, not the variable name. Inside the function, the value is referenced by using the tries<\/code> variable.<\/p>\nattempt<\/code> is a global variable, you can’t use that variable within another function.<\/p>\nint whatever(void);<\/code><\/p>\nchar middle(char *text);<\/code><\/p>\n