[SOLVED] tmux does not honor clear-screen

grobber · 11-25-2018, 02:45 PM

I am on Slackware 14.2, which comes with tmux-2.1.

My $TERM bash variable is set to 'screen' when entering tmux, whereupon pressing Ctrl+l (the usual shortcut to clear the screen) simply produces a new line rather than actually clearing: the behavior is identical to pressing 'Enter'. The same happens with any other shortcut I bind to clear-screen in my .inputrc file. So it seems clear-screen is interpreted as a new line.

Simply issuing the command 'clear' works however, as does 'Ctrl+l' when I start screen rather than tmux (even though in screen the $TERM variable is still 'screen').

I have also briefly packaged and installed the latest tmux I could clone from git with exactly the same results, so this is not due to the relatively old version of tmux.

Finally, it is not clear to me whether this is in any way related to this other tmux problem I posted earlier.

average_user · 11-25-2018, 05:00 PM

Maybe it has something to do with incorrect value of TERMCAP variable or maybe /etc/termcap does not exist on your system at all. Try doing this inside tmux session and check if C-l now works:

Code:

export TERMCAP='SC|screen|VT 100/ANSI X3.64 virtual terminal:\ :DO=\E[%dB:LE=\E[%dD:RI=\E[%dC:UP=\E[%dA:bs:bt=\E[Z:\ :cd=\E[J:ce=\E[K:cl=\E[H\E[J:cm=\E[%i%d;%dH:ct=\E[3g:\ :do=^J:nd=\E[C:pt:rc=\E8:rs=\Ec:sc=\E7:st=\EH:up=\EM:\ :le=^H:bl=^G:cr=^M:it#8:ho=\E[H:nw=\EE:ta=^I:is=\E)0:\ :li#66:co#212:am:xn:xv:LP:sr=\EM:al=\E[L:AL=\E[%dL:\ :cs=\E[%i%d;%dr:dl=\E[M:DL=\E[%dM:dc=\E[P:DC=\E[%dP:\ :im=\E[4h:ei=\E[4l:mi:IC=\E[%d@:ks=\E[?1h\E=:\ :ke=\E[?1l\E>:vi=\E[?25l:ve=\E[34h\E[?25h:vs=\E[34l:\ :ti=\E[?1049h:te=\E[?1049l:us=\E[4m:ue=\E[24m:so=\E[3m:\ :se=\E[23m:mb=\E[5m:md=\E[1m:mr=\E[7m:me=\E[m:ms:\ :Co#8:pa#64:AF=\E[3%dm:AB=\E[4%dm:op=\E[39;49m:AX:\ :vb=\Eg:G0:as=\E(0:ae=\E(B:\ :ac=\140\140aaffggjjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~..--++,,hhII00:\ :po=\E[5i:pf=\E[4i:Km=\E[M:k0=\E[10~:k1=\EOP:k2=\EOQ:\ :k3=\EOR:k4=\EOS:k5=\E[15~:k6=\E[17~:k7=\E[18~:\ :k8=\E[19~:k9=\E[20~:k;=\E[21~:F1=\E[23~:F2=\E[24~:\ :F3=\E[1;2P:F4=\E[1;2Q:F5=\E[1;2R:F6=\E[1;2S:\ :F7=\E[15;2~:F8=\E[17;2~:F9=\E[18;2~:FA=\E[19;2~:\ :FB=\E[20;2~:FC=\E[21;2~:FD=\E[23;2~:FE=\E[24;2~:kb=^H:\ :K2=\EOE:kB=\E[Z:kF=\E[1;2B:kR=\E[1;2A:*4=\E[3;2~:\ :*7=\E[1;2F:#2=\E[1;2H:#3=\E[2;2~:#4=\E[1;2D:%c=\E[6;2~:\ :%e=\E[5;2~:%i=\E[1;2C:kh=\E[1~:@1=\E[1~:kH=\E[4~:\ :@7=\E[4~:kN=\E[6~:kP=\E[5~:kI=\E[2~:kD=\E[3~:ku=\EOA:\ :kd=\EOB:kr=\EOC:kl=\EOD:km:'

grobber · 11-26-2018, 08:17 AM

Quote:

Originally Posted by average_user

Maybe it has something to do with incorrect value of TERMCAP variable or maybe /etc/termcap does not exist on your system at all. Try doing this inside tmux session and check if C-l now works:

Code:

export TERMCAP='SC|screen|VT 100/ANSI X3.64 virtual terminal:\ :DO=\E[%dB:LE=\E[%dD:RI=\E[%dC:UP=\E[%dA:bs:bt=\E[Z:\ :cd=\E[J:ce=\E[K:cl=\E[H\E[J:cm=\E[%i%d;%dH:ct=\E[3g:\ :do=^J:nd=\E[C:pt:rc=\E8:rs=\Ec:sc=\E7:st=\EH:up=\EM:\ :le=^H:bl=^G:cr=^M:it#8:ho=\E[H:nw=\EE:ta=^I:is=\E)0:\ :li#66:co#212:am:xn:xv:LP:sr=\EM:al=\E[L:AL=\E[%dL:\ :cs=\E[%i%d;%dr:dl=\E[M:DL=\E[%dM:dc=\E[P:DC=\E[%dP:\ :im=\E[4h:ei=\E[4l:mi:IC=\E[%d@:ks=\E[?1h\E=:\ :ke=\E[?1l\E>:vi=\E[?25l:ve=\E[34h\E[?25h:vs=\E[34l:\ :ti=\E[?1049h:te=\E[?1049l:us=\E[4m:ue=\E[24m:so=\E[3m:\ :se=\E[23m:mb=\E[5m:md=\E[1m:mr=\E[7m:me=\E[m:ms:\ :Co#8:pa#64:AF=\E[3%dm:AB=\E[4%dm:op=\E[39;49m:AX:\ :vb=\Eg:G0:as=\E(0:ae=\E(B:\ :ac=\140\140aaffggjjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~..--++,,hhII00:\ :po=\E[5i:pf=\E[4i:Km=\E[M:k0=\E[10~:k1=\EOP:k2=\EOQ:\ :k3=\EOR:k4=\EOS:k5=\E[15~:k6=\E[17~:k7=\E[18~:\ :k8=\E[19~:k9=\E[20~:k;=\E[21~:F1=\E[23~:F2=\E[24~:\ :F3=\E[1;2P:F4=\E[1;2Q:F5=\E[1;2R:F6=\E[1;2S:\ :F7=\E[15;2~:F8=\E[17;2~:F9=\E[18;2~:FA=\E[19;2~:\ :FB=\E[20;2~:FC=\E[21;2~:FD=\E[23;2~:FE=\E[24;2~:kb=^H:\ :K2=\EOE:kB=\E[Z:kF=\E[1;2B:kR=\E[1;2A:*4=\E[3;2~:\ :*7=\E[1;2F:#2=\E[1;2H:#3=\E[2;2~:#4=\E[1;2D:%c=\E[6;2~:\ :%e=\E[5;2~:%i=\E[1;2C:kh=\E[1~:@1=\E[1~:kH=\E[4~:\ :@7=\E[4~:kN=\E[6~:kP=\E[5~:kI=\E[2~:kD=\E[3~:ku=\EOA:\ :kd=\EOB:kr=\EOC:kl=\EOD:km:'

That's exactly what it was: I hadn't realized many of Slackware's shells still use termcap rather than terminfo. Sorted it out on the tmux github page. What worked in the end:

export TERM=screen
infocmp > some_temporary_file (this gets the terminfo data for screen)
tic -C some_temporary_file >> /etc/termcap

That's it! Now /etc/termcap will know what to do when TERM=screen. The same applies to whatever other terminals are problematic. I did the same for 'xterm-256color' (in place of 'screen') for instance, to have 'ctrl+l' functionality when I ssh into my Slackware machine from computers that use that terminal style.

Thank you! I'll mark this as 'solved'.