What does -std=c99 command do?

Question

When I run make, I see a lots of clang commands. I know the meaning of all of them except -std=c99. So, what does this command do?

Answer 1

The C programming language has many versions. -std=c99 lets the compiler know that we're using the standard version C99 (released in 1999).

See more: http://en.m.wikipedia.org/wiki/C99

Answer 2

adding further , this version of C has many cool new features which every programmer uses presently , like - single line comments starting with //

initialising varibales where they are implemented-

old school C -
int i; for (i=0; condition ; operation)

C99 - for (int i=0; condition ; operation)