Functions in C

COMP281 Lectures 2022-02-17

A fragment of code that accepts zero of more argument values, produces a result value and has zero or more side effects.

Arguments

By default arguments are passed by value:

int main (void) {
	putInFridge(eggs)
	return 0;
}

This means that if the variable changes in the function, the change is not made outide the function.

Library Functions

math.h

• sin(x) - (Radians)
• cos(x) - (Radians)
• tan(x) - (Radians)
• atan(x)
• atan2(y,x)
• exp(x) - ($e^x$)
• log(x) - ($\log_e x$)
• log10(x) - ($log_{10} x$)
• sqrt(x) - ($x \geq 0$)
• pow(x, y) ($x^y$)

string.h

• strcpy()
• strcat()
• strcmp()
• strlen()

stdio.h

• printf()
• fprintf()
• scanf()
• sscanf()

Function Definition Syntax

returnType functionName(type1 parameter1, ...) {
	// function body
}