Awk is a maintenance and processing of text data files, powerful programming language.
When the text data of a certain format, i.e., each row of data contains a plurality of fields to boundary-delimited especially useful.
Awk basic grammar:
Awk -Fs '} {Command' INPUT-File
-F as field delimiters. If not specified, the default will use the space as a delimiter
A typical awk program comprises the following three regions:
- BEGIN region
syntax Begin region: BEGIN {awk-commands} BEGIN command areas initially only performed once before awk command execution body region. BEGIN area very suitable for printing packet header information, and is used to initialize variables. BEGIN area may have one or more awk command capital must use the keyword BEGIN BEGIN field is optional - body region
syntax body area: / pattern / {action} body region read each command line from the input file will be executed if the input file has a row 10, that will execute the command body region 10 (one per line executed once) Body region is not represented only by a regular mode and command by any keyword. - END Block
Syntax END region: END {awk-commands} END region awk After all operations performed, and is performed only once. END region is very suitable for newspaper printing the end of file information, as well as to do some cleanup actions END region may have one or more awk command keyword END must use uppercase END field is optional
When it encounters a file containing a plurality of field delimiter, do not worry, FS can handle. You can use regular expressions to specify multiple field separator, such as FS = "[,:%] " designated field delimiter can be a comma or semicolon: Percent or%.
awk 'BEGIN {FS = "[ ,:%]"} {print $ 2, $ 3}' employee-multiple-fs.txt
OFS - Output Field Separator
awk -F ‘,’ ‘BEGIN {OFS=":"} {print $2,$3}’ employee.txt
Also, please note that the print statement manipulation