Page break characters for more/less

Question

I am on Mac OS. I have a C++ program that generates 1000+ lines of data that I redirect to a file. I then use less / more to go through the file. I'd like to have less pause at user-defined chunks of data instead of of pausing every screenful. I thought I could use the ^L character to mark page breaks, but even after adding them in my C++ code with

        printf("control-l \n");

the less command on my Mac will still pause at every screenful instead of at each control-L.

I remember from decades ago that this worked on Unix. Do I need to do something different here?

Answer 1

Not a page break, but the 'u' and 'd' keys can be set to scroll the screen however many lines you want. By default, pressing these keys scrolls the file by half a screen 'u'p and 'd'own. But if you type a number before pressing either key, both keys will start scrolling the file by the number of lines you specified.

less file:
  10d ; scrolls the file down 10 lines
  d   ; scrolls the file down another 10 lines
  u   ; scrolls the file up 10 lines
  25d ; scrolls the file down 25 lines
  d   ; scrolls the file down 25 lines
  u   ; scrolls the file up 25 lines
  5u  ; scrolls the file up 5 lines
  d   ; scrolls the file down 5 lines

Note: I'm using the GNU version of less on Debian Linux. The Mac version could be different.

Answer 2

less doesn’t pause at formfeeds, but you can achieve the same effect by searching for them: / CtrlV CtrlL Enter. Press n to jump to the next formfeed, or N to go back to the previous one.