{"thread":{"id":"5982","subject":"less -F ubuntu dapper.","startedAt":"2006-10-21T13:23:35Z","lastAt":"2006-10-21T16:47:06Z","messageCount":3,"participants":["Aneesh Kumar","Sergey Vlasov","A Large Angry SCM"],"isPatch":false,"patchVersion":null,"patchTotal":null},"messages":[{"id":"29493","messageId":"cc723f590610210623sbee2075i5f2fd441cceb84ae@mail.gmail.com","threadId":"5982","inReplyTo":null,"subject":"less -F ubuntu dapper.","fromName":"Aneesh Kumar","fromEmail":"aneesh.kumar@gmail.com","sentAt":"2006-10-21T13:23:35Z","receivedAt":"2006-10-21T13:23:35Z","isPatch":false,"sender":{"key":"aneesh.kumar@gmail.com","avatar":"https://gravatar.com/avatar/0621fc0b2f14ead1e9024382f16053a808c148596da30c1b92572fa075621f68?d=mp&s=160"},"body":"-F option for less in ubuntu Dapper is broken. It doesn't display\nanyting if the file can be displayed in one page. Because of this the\nrecent chages to\n96a035d1db9082d244867033020d0ceb571cf94e results in commands like git\nshow not showing the changes.\n\nhttps://launchpad.net/distros/ubuntu/+source/less/+bug/67381\n\n\n-aneesh\n"},{"id":"29511","messageId":"20061021200110.6aef96a4.vsu@altlinux.ru","threadId":"5982","inReplyTo":"cc723f590610210623sbee2075i5f2fd441cceb84ae@mail.gmail.com","subject":"Re: less -F ubuntu dapper.","fromName":"Sergey Vlasov","fromEmail":"vsu@altlinux.ru","sentAt":"2006-10-21T16:01:10Z","receivedAt":"2006-10-21T16:01:10Z","isPatch":false,"sender":{"key":"vsu@altlinux.ru","avatar":"https://avatars.githubusercontent.com/u/616082?v=4"},"body":"On Sat, 21 Oct 2006 18:53:35 +0530 Aneesh Kumar wrote:\n\n> -F option for less in ubuntu Dapper is broken. It doesn't display\n> anyting if the file can be displayed in one page.\n\nSame here in ALT Linux (less-382-alt2).  The problem appears only\nwhen the terminal supports alternate screen, and less uses it.\n\nBTW, try this (needs bash or zsh):\n\n  (for ((i=0; i < 20; ++i)) do echo $i; sleep 0.1; done) | less -F\n\nYou'll see that the text appears on the screen while the loop\noutputs it, but disappears once the output finishes.  If you use\n\"less -FX\" instead, the text will not disappear, but in this case\nless will not use the alternate screen, which is inconvenient when\nthe text is large (e.g., when you browse the text, parts of it\nwill be put into the scrollback buffer).\n\nBecause less must start displaying the text immediately after it\ngot some data, it cannot decide whether to use the alternate\nscreen depending on the text size.  Therefore, if you want to use\nthe -F option on a terminal with alternate screen, you need to\nturn off the alternate screen support with -X.  But less cannot do\nthis automatically, because it does not really know about the\nalternate screen (the -X option disables termcap initialization\nand deinitialization strings, which can do arbitrary things, and\nmay actually be required on some obscure terminals).\n\nIt should be possible to add yet another option to less to make it\ninitially display the text on the alternate screen, and on EOF, if\nthe text fits on the screen, turn off the alternate screen,\n_redisplay the text_ and exit.  However, this option will have\neven more assumptions about the terminal than -X (if the terminal\ndoes not turn on alternate screen in its termcap initialization\nstring, there will be a horrible mess on screen), and you will get\nflicker when the text is displayed multiple times.\n\n> Because of this the recent chages to\n> 96a035d1db9082d244867033020d0ceb571cf94e results in commands\n> like git show not showing the changes.\n\nAdding the -X option might break some terminals (and will irritate\nusers which used alternate screen before), so apparently the only\nway to fix this breakage is to remove the -F option again...\n"},{"id":"29517","messageId":"453A4F0A.9000003@gmail.com","threadId":"5982","inReplyTo":"20061021200110.6aef96a4.vsu@altlinux.ru","subject":"Re: less -F ubuntu dapper.","fromName":"A Large Angry SCM","fromEmail":"gitzilla@gmail.com","sentAt":"2006-10-21T16:47:06Z","receivedAt":"2006-10-21T16:47:06Z","isPatch":false,"sender":{"key":"gitzilla@gmail.com","avatar":"https://gravatar.com/avatar/354625c442439908ff3dd99757dee330e29e9df7847472384faf7a00add247fb?d=mp&s=160"},"body":"Sergey Vlasov wrote:\n> On Sat, 21 Oct 2006 18:53:35 +0530 Aneesh Kumar wrote:\n> \n>> -F option for less in ubuntu Dapper is broken. It doesn't display\n>> anyting if the file can be displayed in one page.\n> \n> Same here in ALT Linux (less-382-alt2).  The problem appears only\n> when the terminal supports alternate screen, and less uses it.\n\nSuse 9.3 has the same problem.\n"}]}