printf

We can format our printout with printf according to the following structure. Here we do not use OFS, but format string.

$ awk 'BEGIN {printf("%d %s %.3f\n", 42, "some text", 42)}'
42 some text 42.000
$ awk 'BEGIN {printf "%d %s %.3f\n", 42, "some text", 42}'
42 some text 42.000

In other words, the parentheses are optional. We can see three types of formatting %d,%s and %.3f. The are called “Format-Control letters”:

• %s (string)
• %d (decimal number, integer)
• %f (floating point notation)

There are of course even more, but they will not be included in the course.

If we want to control “padding”, we can set it with positive or negative numbers:

$ awk 'BEGIN {printf("%10d %s %.3f\n", 42, "some text", 42)}'
        42 some text 42.000
$ awk 'BEGIN {printf("%-10d %s %.3f\n", 42, "some text", 42)}'
42         some text 42.000

Read more about control letters.

#Revision history