Variables | Description |
---|---|
ENVIRON | An associative array of environment variables. |
FIELDWIDTHS | Specify the field width |
FS | The field seperator |
RS | The record seperator, default is new line |
NF | The number of fields in the current record |
NR | The number of the current record |
FNR | Similar to NR, but relative to the current file. It is useful when AWK is operating on multiple files. Value of FNR resets with new file. |
OFS | The output field seperator, space by default |
ORS | The output record seperator |
FILENAME | Hold the processed file name |
IGNORECASE | Ignore character case |
$n | The nth field in the current record where the fields are separated by FS |
Source: Mastering Linux Shell Scripting & AWK-Built-in Variables