Bug 208420

Summary: /usr/bin/less incorrectly displays long lines
Product: Base System Reporter: Dmitry Marakasov <amdmi3>
Component: binAssignee: freebsd-bugs (Nobody) <bugs>
Status: Closed Overcome By Events    
Severity: Affects Many People    
Priority: ---    
Version: CURRENT   
Hardware: Any   
OS: Any   

Description Dmitry Marakasov freebsd_committer freebsd_triage 2016-03-31 14:15:09 UTC 
less in -current is terminally broken when handling long lines.

The problem is demostrated on the video:
http://people.freebsd.org/~amdmi3/out.ogv

First, more is called, it correctly scrolls the file from top to bottom.
Less, though, displays `END' right away like the file is shorter than terminal height and does not let scroll at all. It only displays 5 last lines of the file and a part of previous line.

The problem may also be reproduced when scrolling through `pstree` output with a long of long commands running. less will skip lines and eat away long ones.
Comment 1 Dmitry Marakasov freebsd_committer freebsd_triage 2016-03-31 14:16:04 UTC 
IMO that's a blocker for 11.0-RELEASE.
Comment 2 Dmitry Marakasov freebsd_committer freebsd_triage 2016-03-31 14:17:34 UTC 
That's reproducible in FreeBSD 11.0-CURRENT #0 r295763, but was an issue in current for some time.