What can I use for input conversion instead of scanf?

Question

I have very frequently seen people discouraging others from using scanf and saying that there are better alternatives. However, all I end up seeing is either

Answer 1

Other answers give the right low-level details, so I'll limit myself to a higher-level: First, analyse what you expect each input line to look like. Try to describe the input with a formal syntax - with luck, you will find it can be described using a regular grammar, or at least a context-free grammar. If a regular grammar suffices, then you can code up a finite-state machine which recognizes and interprets each command-line one character at a time. Your code will then read a line (as explained in other replies), then scan the chars in the buffer through the state-machine. At certain states you stop and convert the substring scanned thus far to a number or whatever. You can probably 'roll your own' if it is this simple; if you find you require a full context-free grammar you are better off figuring out how to use existing parsing tools (re: lex and yacc or their variants).