awk '/the_string/{getline; print}' file.txt
Assuming a file, test.txt, exists with the following contents:
10 Peter Terence Roux 45 11 Virginia Genevieve Roux 45 12 Felix Devon Roux 5 13 David Bruce Stevenson 48 14 Bob James Smith 16 48 Adam Winter Ridley 23
Running
awk '/Peter/{getline; print}' test.txt
returns:
11 Virginia Genevive Roux 45
NOTE: This simply returns the next line after the search string of Peter.
Running
awk '/Roux/{getline; print}' test.txt
returns:
11 Virginia Genevieve Roux 45 13 David Bruce Stevenson 48
NOTE: This finds the search string Roux in row 10, so it includes the next row 11 in the result; even though row 11 also contains the same search string.
It then proceeds with row 12 which also contains the search string Roux, so it includes row 13 in the results.
No further rows contain the search string so nothing else is added to the result.
Running
awk '/4/{getline; print}' test.txt
returns:
11 Virginia Genevieve Roux 45 14 Bob James Smith 16 48 Adam Winter Ridley 23
NOTE: This finds the search string 4 in row 10, so it includes the next row 11 in the result; even though row 11 also contains the same search string.
It then proceeds from row 12. It does not find the search string 4, so moves to row 13.
In row 13 it finds the search string 4, so it includes the next row 14 in the results; even though row 14 also contains the same search string.
It then proceeds from row 15.
The last row contains the search string; and as there is no other row below that can be added to the result; the last row itself is added. Possibly a bug?