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Secure C Programming Practices

• Avoid single argument printf. If you just need to print a string, use puts as it will terminate with a newline character. If we must use printf() for a string that does not terminate with a new line character, we could use %s followed by the string replacement.
• Be aware of arithmetic overflow. Values that become too large to store into a variable. Use limits.h defined constants to ensure that an operation that does not overflow. Also, if a variable cannot possibly negative in a contextual sense, use the unsigned version of it.
• Rid yourself of warnings when compiling a program.
• Always check the return value of scanf. scanf returns an integer. 1 if it was read correctly and 0 if it was unable to parse a given value. This is useful for checking if the user is inputting a valid value into your program, or not.
• Validate values in your program to see if they are valid.
• Bounds checking for array indices.