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Introduction to the printf Statement

A simple printf statement looks like this: 

printf format, item1, item2, ...

The entire list of arguments may optionally be enclosed in parentheses. The parentheses are necessary if any of the item expressions use the > relational operator; otherwise, it can be confused with a redirection (see Redirecting Output of print and printf).

The difference between printf and print is the format argument. This is an expression whose value is taken as a string; it specifies how to output each of the other arguments. It is called the format string.

The format string is very similar to that in the ISO C library function printf. Most of format is text to output verbatim. Scattered among this text are format specifiers--one per item. Each format specifier says to output the next item in the argument list at that place in the format.

The printf statement does not automatically append a newline to its output. It outputs only what the format string specifies. So if a newline is needed, you must include one in the format string. The output separator variables OFS and ORS have no effect on printf statements. For example: 

$ awk 'BEGIN {
>    ORS = "\nOUCH!\n"; OFS = "+"
>    msg = "Dont Panic!"
>    printf "%s\n", msg
> }'
-| Dont Panic!

Here, neither the + nor the OUCH appear when the message is printed.