To read a file line by line using awk, you can use the following syntax:
awk '{ code }' input_file
This will execute the code block for each line in the input_file. The code block can contain any valid awk commands, such as print or if statements.
For example, to print each line of a file, you can use the following command:
awk '{ print }' input_file
This will print each line of the input_file to the terminal.
You can also use variables to store and manipulate data from the file. For example, to store the first field of each line in a variable called field1, you can use the following command:
awk '{ field1 = $1 }' input_file
This will store the first field of each line in the field1 variable. You can then use the field1 variable in other awk commands, such as a print statement:
awk '{ field1 = $1; print field1 }' input_file
This will print the first field of each line to the terminal.
It's important to note that awk processes the input file line by line, so it is efficient for reading large files. Consult the awk documentation and online resources for more information on how to use awk to read and process a file line by line.