An Awk Primer/Numbers and Strings
Numbers
editNumbers can be expressed in Awk as either decimal integers or floating-point quantities. For example:
789
3.141592654
+67
+4.6E3
-34
-2.1e-2
There is no provision for specifying values in other bases, such as hex or octal; however, as will be shown later, it is possible to output them from Awk in hex or octal format.
Strings
editStrings are expressed in double quotes. For example:
"All work and no play makes Jack a homicidal maniac!"
"1987A1"
"do re mi fa so la ti do"
Awk also supports null strings, which are represented by empty quotes: ""
.
Like the C programming language, it is possible in Awk to specify a character by its three-digit octal code (preceded by a backslash).
There are various "special" characters that can be embedded into strings:
\n
Newline (line feed)\t
Horizontal tab (aligns to next column of 8 spaces)\b
Backspace\r
Carriage return\f
Form feed (possibly causes a new page, if printing)
A double-quote ("
) can be embedded in a string by preceding it with a backslash, and a backslash can be embedded in a string by typing it in twice: \\
. If a backslash is used with other characters (say, \m
), it is simply treated as a normal character.