UUU: Multi-line grep with AWK

UUU - Unbelievably Useful Utilities:

I will be talking more about awk, awk vs. perl later, but this time I would like to demonstrate how easy it is to have versatile multi-grep functionality using AWK.

The goal is to print previous or next line that follows/goes before a line consisting of dashes (i.e. comments in C++/Java, text file with headings, etc.).

The text file is

test.txt
before line 1
--------
after line 1
x
y
z
before line 2
--------
after line 2
x
y
z
before line 3
--------
after line 3
x
y
z

---

grepAfter.awk

/^-+$/{



  getline nextLine

 print nextLine

}

Command line:
awk -f grepAfter.awk test.txt

Output Listing:
after line 1
after line 2
after line 3

---

grepBefore.awk

/^-+$/{



 print prevLine

}

{

 prevLine = $0

}

Command line:
awk -f grepBefore.awk test.txt

Output Listing:
before line 1
before line 2
before line 3

---