LinuxQuestions.org
View the Most Wanted LQ Wiki articles.
Go Back   LinuxQuestions.org > Forums > Linux > Linux - Software
User Name
Password
Linux - Software This forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.

Notices

Tags used in this thread
Popular LQ Tags , ,

Reply
 
Thread Tools
Old 03-13-2008, 02:33 PM   #1
deepclutch
Member
 
Registered: Nov 2004
Location: kerala,India
Distribution: Ubuntu Intrepid,Fedora 10
Posts: 645
Thanked: 0
Smile "less" command output-I cannot scroll through it !


[Log in to get rid of this advertisement]
Hi all,
well,I am on archlinux with kdemod.
now,in konsole I can scroll through the output and even scroll through file contents in nano or vim
editors.
But,if I use "less" utility,
like "less /var/log/auth.log"
I cannot scroll with mouse wheel!
although,pageup ,pagedown etc works.
what should I look for?my env variables seems fine.and "less" is the latest version/
waiting....pls reply

Thanks
deepclutch is offline  
Tag This Post , ,
Reply With Quote
Old 03-14-2008, 12:32 AM   #2
deepclutch
Member
 
Registered: Nov 2004
Location: kerala,India
Distribution: Ubuntu Intrepid,Fedora 10
Posts: 645
Thanked: 0

Original Poster
guys,Im clueless.pls help me
deepclutch is offline     Reply With Quote
Old 03-14-2008, 12:59 AM   #3
konsolebox
Member
 
Registered: Oct 2005
Location: Philippines
Distribution: Gentoo, Slackware
Posts: 957
Thanked: 15
less simply only accepts standard (keyboard) input.. perhaps it's possible but i'm not sure if less can be configured to accept input from /dev/mouse or the like and let it process the mouse input.

To get things a little bit clearer, konsole only manipulates output that was already written in the screen.. while less reclears and then reprints again data back and forth for every key command like up, down, pageup or pagedown etc. konsole doesn't care what program runs within it as long as it caches every output and that's it. try cat-ing a file in konsole then do 'clear' and then scroll up you'll see that still a remaining of the texts where not cleared. That's because only a little part of the lines where cleared and some of the caches still remains..
konsolebox is offline     Reply With Quote
Old 03-14-2008, 01:13 AM   #4
matthewg42
Senior Member
 
Registered: Oct 2003
Location: UK
Distribution: Kubuntu (x86), Debian (PPC)
Posts: 3,495
Thanked: 6
Curiously, gnome-terminal will somehow translate mouse wheel events into a form which less can understand. konsole doesn't do this. I never got round to finding out how gnome-terminal does this, or if it's possible to get konsole to do it. I would like to know!
matthewg42 is offline     Reply With Quote
Old 03-14-2008, 01:47 AM   #5
konsolebox
Member
 
Registered: Oct 2005
Location: Philippines
Distribution: Gentoo, Slackware
Posts: 957
Thanked: 15
Hello matthewg42. I'm interested to make that happen.. can you tell me how gnome-terminal was able to make less understand mouse wheel events? It seems that it doesn't work as default in a gnome terminal of a box near me.
konsolebox is offline     Reply With Quote
Old 03-14-2008, 01:53 AM   #6
deepclutch
Member
 
Registered: Nov 2004
Location: kerala,India
Distribution: Ubuntu Intrepid,Fedora 10
Posts: 645
Thanked: 0

Original Poster
gnome-terminal works fine.
but the weird thing is ,I can scroll through file contents in vim/nano using mouse wheel :? also throught any output in konsole!for eg:cat /etc/issue o/p :|
xterm also does not support the scrolling of "less" contents

and mouse device is (I use a 3 button logitech optical mouse with a wheel+button) /dev/input/mice in my Debian as well as archlinux.
/dev/psaux,/dev/input/mouse0,/dev/input/mouse1 etc exists.



what can be done?Is there some env variable that messes whole thing?
Thank you all!
deepclutch is offline     Reply With Quote
Old 03-14-2008, 02:05 AM   #7
konsolebox
Member
 
Registered: Oct 2005
Location: Philippines
Distribution: Gentoo, Slackware
Posts: 957
Thanked: 15
Quote:
Originally Posted by deepclutch View Post
gnome-terminal works fine.
but the weird thing is ,I can scroll through file contents in vim/nano using mouse wheel :? also throught any output in konsole!for eg:cat /etc/issue o/p :|
xterm also does not support the scrolling of "less" contents

and mouse device is (I use a 3 button logitech optical mouse with a wheel+button) /dev/input/mice in my Debian as well as archlinux.
/dev/psaux,/dev/input/mouse0,/dev/input/mouse1 etc exists.

what can be done?Is there some env variable that messes whole thing?
Thank you all!
are you sure you're seeing the keyboard cursor in vim move up and down or just the terminal? you can verify this if position number in lower right ofthe screen changes during scroll.
konsolebox is offline     Reply With Quote
Old 03-14-2008, 02:14 AM   #8
deepclutch
Member
 
Registered: Nov 2004
Location: kerala,India
Distribution: Ubuntu Intrepid,Fedora 10
Posts: 645
Thanked: 0

Original Poster
no,cursor and select tool(gpm?) rests where it was at original position.while the terminal scrolls fine up and down directions.

if I press left mouse button somewhere,the cursor and select tool comes there. weird is that "less" is not achieving this!.

out of curiousity,any konsole user can confirm whether "less" allows scrolling in konsole?
deepclutch is offline     Reply With Quote
Old 03-14-2008, 10:52 AM   #9
deepclutch
Member
 
Registered: Nov 2004
Location: kerala,India
Distribution: Ubuntu Intrepid,Fedora 10
Posts: 645
Thanked: 0

Original Poster
pss... help?
deepclutch is offline     Reply With Quote
Old 03-14-2008, 01:04 PM   #10
matthewg42
Senior Member
 
Registered: Oct 2003
Location: UK
Distribution: Kubuntu (x86), Debian (PPC)
Posts: 3,495
Thanked: 6
Quote:
Originally Posted by konsolebox View Post
Hello matthewg42. I'm interested to make that happen.. can you tell me how gnome-terminal was able to make less understand mouse wheel events? It seems that it doesn't work as default in a gnome terminal of a box near me.
I don't know how it works. Just that it does on Ubuntu 7.10.
matthewg42 is offline     Reply With Quote
Old 03-14-2008, 03:02 PM   #11
osor
HCL Maintainer
 
Registered: Jan 2006
Distribution: (H)LFS, Gentoo
Posts: 2,434
Thanked: 24
Quote:
Originally Posted by matthewg42 View Post
Curiously, gnome-terminal will somehow translate mouse wheel events into a form which less can understand. konsole doesn't do this. I never got round to finding out how gnome-terminal does this, or if it's possible to get konsole to do it.
There is a hackish way to do this externally. Use the imwheel daemon to bind to Konsole windows of a specific window title and translate mouse scroll events as arrow key movements. Then, make an alias to less which changes the window title, runs less with whatever arguments, and then reverts the title.
osor is offline     Reply With Quote
Old 03-14-2008, 03:35 PM   #12
ararus
Member
 
Registered: Mar 2008
Location: UK
Distribution: Slackware
Posts: 56
Thanked: 0
Quote:
can you tell me how gnome-terminal was able to make less understand mouse wheel events? I
You can't make less understand mouse events. Mouse events are a GUI concept, less is a console application.

You can, however, as matthewg42, stated, have the xterminal program translate mouse events into suitable key presses.

Rxvt (and I guess Xterm) uses the sequences '\e[?1000h' and '\e[?1000l' to turn mouse reporting on/off respectively. I don't use KDE but I would imagine that Konsole supports those sequences too.

Just echo it to the console, make sure you use the -e option to enable escape character processing, i.e.

echo -e '\e[?1000h'

Of course, that just dumps the translated escape sequence to the console, getting a program to understand them is another matter, but as long as the app has configurable key bindings (well, key sequence bindings), it should be easy enough.

Note that you will see just a bunch of crap on the screen because your shell will attempt to interpret the sequence. Use a program that reads from stdin (e.g. tail or hexdump without args) and you will see the actual escape sequence, something like: '^[[M#i'

hexdump might be better than tail, as it will show you the ascii codes of the characters (could be a space in there or something).

With rxvt (I assume xterm etc is the same), the output is in the format:

ESC [ M <b> <x> <y>

b is the button number (0, 1, or 2 for first, second, third button)

Annoyingly though, button releases are not interpreted individually, you just get a button number of 3 on release regardless of which button was released. Still, that shouldn't be a big deal, as most console apps will act on the press (for scrolling etc), not the release.

x y is the character position on screen, of course.

Last edited by ararus; 03-14-2008 at 03:47 PM..
ararus is offline     Reply With Quote
Old 03-14-2008, 05:13 PM   #13
Tinkster
Moderator
 
Registered: Apr 2002
Location: in a fallen world
Distribution: slackware by choice, others too :}
Posts: 18,849
Blog Entries: 1
Thanked: 160
Quote:
Originally Posted by deepclutch View Post
guys,Im clueless.pls help me :)
But that doesn't warrant ignoring our rules.

DON'T bump your posts before 24 hours are up.



Cheers,
Tink
Tinkster is offline     Reply With Quote
Old 03-14-2008, 05:14 PM   #14
Tinkster
Moderator
 
Registered: Apr 2002
Location: in a fallen world
Distribution: slackware by choice, others too :}
Posts: 18,849
Blog Entries: 1
Thanked: 160
Quote:
Originally Posted by deepclutch View Post
pss... :( help?
And again. Stop that. You've been on LQ for long
enough to know better.



Cheers,
Tink
Tinkster is offline     Reply With Quote
Old 03-15-2008, 12:22 AM   #15
konsolebox
Member
 
Registered: Oct 2005
Location: Philippines
Distribution: Gentoo, Slackware
Posts: 957
Thanked: 15
Quote:
Originally Posted by ararus View Post
You can't make less understand mouse events. Mouse events are a GUI concept, less is a console application.

You can, however, as matthewg42, stated, have the xterminal program translate mouse events into suitable key presses.
Sorry i bypassed in my question.. that' what i really mean.. doing some kind of mouse wheel event wrappers that will send messages to less that less can understand. If we make less directly read the mouse, it would require a whole new addition of codes to less.

But nice and cool info. I'll try that when I get back to my linux box. Have a nice weekend.
konsolebox is offline     Reply With Quote

Reply

Bookmarks


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Standard commands give "-bash: open: command not found" even in "su -" and "su root" mibo12 Linux - General 4 11-11-2007 11:18 PM
change "who" command output khairilthegreat Linux - Newbie 5 07-26-2007 03:36 AM
unknown entry in the output of "df -h " command Balakrishna Linux - Newbie 1 12-19-2006 01:17 AM
how do i remove unwanted charaters at "script" command output? linuxzouk Linux - Newbie 4 05-15-2004 08:58 AM
qmail: strange output of "file" command slowleak Linux - Security 1 08-10-2001 11:40 PM


All times are GMT -5. The time now is 07:53 AM.

Main Menu
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
RSS2  LQ Podcast
RSS2  LQ Radio
Twitter: @linuxquestions
identi.ca: @linuxquestions
Facebook: @linuxquestions
Open Source Consulting | Domain Registration