How to use "awk" to do the following seemingly simple work?
1) Given an input file, I want to perform some action to a line subject to some conditions of the next line. For example,
if the next line is "======" then I want to print the current line.
How can such actions be performed using awk?
2) Is there any method for awk to go back one/more line(s) when reading a file?
3) What is the difference between these two intrinsic variables: NR and FNR?
4) Does awk support multidimensional array?